Dictionary of gynaecological terms

When the patient stops the treatment course for personal reasons.

The removal of tissue by surgery, laser, cryotherapy or electricity.

Anaerobic bacteria in the oral cavity reservoir, which may be associated with colonisation of intrauterine devices and the production of pelvic infections and abscesses.

Malignant tumour whose cells come from glandular epithelium.

Growth of endometrial tissue in the thickness of the uterine myometrium, associated with a growing uterus, and menstrual pain.

Abnormal fusion between tissues. It may occur at the level of the labia minora (girls), uterus (Asherman syndrome) and in the pelvic region through inflammation or endometriosis.

Relating to the accessories to the female genital tract, mainly the ovaries, fallopian tubes and uterine ligaments.

Time of existence calculated from birth. Very important for women in order to assess ovarian reserve and a determining influence on the chances of successful pregnancy and assisted reproductive techniques. Gestational age marks the duration of pregnancy from the last period.

Plasma protein produced by the foetal liver and yolk sac, which has been used as part of prenatal screening in the second trimester of pregnancy to assess the risk of Down syndrome. Its increase in blood is also associated with neural tube defects and in adults testicular tumours and liver tumours.

Absence of menstruation. Primary when you haven't had your first period by the age 16. Secondary if menstruation ends at least 3 months after having been established. Physiological during periods of pregnancy, lactation, prepuberty and menopause. Hypothalamic when ovarian function fails at the central neurologic level.

Diagnostic testing of amniotic fluid taken via transabdominal puncture (foetal karyotype, microbiological, foetal lung maturity, biochemical) or for therapeutic purposes (hydramnios).

Diagnostic testing of amniotic fluid taken via transabdominal puncture (foetal karyotype, microbiological, foetal lung maturity, biochemical) or for therapeutic purposes (hydramnios).

Infusion of saline into the amniotic cavity, useful in cases of oligohydramnios, meconium or prevention of umbilical cord compression.

Innermost ovular membrane which is host to the embryo and the amniotic fluid.

Infection and inflammation of the amnion, which will lead to uterine contractions and / or rupture of amniotic membranes.

Losing of amniotic fluid through the vagina.

Direct visualisation of the amnion and amniotic fluid through a tube (amnioscope) introduced through the uterine cervix.

artificial rupture of the amnion using a lancet.

anaesthesia technique designed to reduce or avoid pain. It can be local, regional (epidural) or systemic.

Group of hormones that induce development of male sexual characteristics.

Specialist in the study and treatment of sexual and reproductive function in men.

Congenital defect that is associated with the absence of the brain shell which is incompatible with life.

Congenital absence of one or both male gonads or testes.

Absence of ovulation and therefore associated with infertility. The most common cause of chronic anovulation is polycystic ovarian syndrome.

The tilting forward of the uterine axis

The tilting forward of the uterine axis

Immunoglobulin (defense) produced by specific B lymphocytes in response to a specific antigen (aggressor).

Any substance that can block the action of oestrogen on the body.

The oocyte retrieval is performed vaginally with ultrasound guidance

Decrease in sperm motility of a semen sample.

Loss of tone or tension of an organ. Uterine atony is a lack of contraction of the uterus after expulsion of the foetus and placenta which results in puerperal hemorrhage with high morbidity and mortality.

Process triggered by the effect of the individual's own immune system acting against it, causing disease or illness.

Absence of sperm in a sample of ejaculate in both direct observation and following centrifugation of the sample. Two samples are needed to confirm the diagnosis. Secretory azoospermia is caused by primary failure of the hypothalamic-pituitary-testcular system.Obstructive azoospermia alteration in the sperm conduction and storage system.

Pregnancy-specific hormone produced by trophoblast cells and used in different blood or urine tests to confirm pregnancy.

Inflammation of the Bartholin glands situated at the entrance of the vagina and whose job is to lubricate.May evolve into an abscess requiring surgical drainage.

The measure used to determine the day of ovulation and thus, highest fertility.

Pregnancy in which there is only HCG hormone production, without actually visualized gallbladder ultrasound gestational inside the uterus.

Taking cells from a portion of tissue for histological analysis.

Embryo in the 5th day of development and the phase in which implementation will occur inside the uterus.

Each one of the cells that form the embryo and at their core is the same genetic information.

Small hermetically sealed glass container containing a drug for parenteral administration (intramuscular, subcutaneous or intravenous).

Local application of radiation by small sources of radiation placed directly on or near the tissue to be treated.

Tear or bursting of any corporal organ.

The application of external pressure, for example: to inhibit bleeding.

antigens often found in increased levels in malignant ovarian tumours, especially serous ones. They may be elevated but more moderately so in endometriosis.

antigen that is usually elevated in malignant breast tumours.

high antigen commonly found in malignant ovarian tumours, especially mucinous as well as in Fallopian tube carcinomas.

This happens when the medical team decides to stop treatment for a problem. For example due to poor ovarian response or a risk of hyperstimulation.

Yeast usually colonises the digestive tract and can spread and cause infections at other levels, especially in the vulvo-vaginal area. Infection increases during pregnancy, if in a state of immunosuppression, with diabetes, while taking antibiotics during a long period of time and with contraceptive use. The symptomatology is characterised by itching, burning and a white, thick, and dense discharge.

Morphological, functional and biochemical changes which occur in the sperm and which allow the acrosome reaction and the fertilisation of the oocyte.

Cylindrical instrument, often curved, used to explore a body cavity or to widen a channel or tubular structure.

A flexible, tubular instrument made from plastic, latex or silicone that is inserted into a cavity to deposit a certain element in it. It is used to transfer embryos into the endometrial cavity or to deposit sperm into the fundus.

Functional unit of all living things, consisting of a nucleus (containing genetic information) and cytoplasm (containing the various organelles).

Migraine. It may be cyclical, related to menstruation, localised (temporal, occipital), fixed or pulsed. It can occur after epidural anaesthesia through accidental dural puncture.

Surgical treatment for cervical incompetence and is associated with late abortions and immature births. It consists of suturing the uterine cervix between 12 to 14 weeks of pregnancy.

Mixture of mucin, cells, water and inorganic salts, secreted by glands inside the cervical canal, influenced by periodic hormonal changes under the influence of estrogen is extremely thin and flexible, just before ovulation , under the dominance of progestogens is thick and slimy. During pregnancy it becomes more abundant and forms a plug that fills and closes the channel entirely.

Inflammation of the cervix, usually secondary to sexually transmitted diseases and sometimes trauma.

Lower portion or the neck of the uterus, readily visible during the vaginal speculum examination. The cervical canal connects to the uterus inside the vagina.

Genital ulcer corresponding to the site of the Treponema pallidum inoculation, the causative agent of syphilis, which is acquired through sexual contact.

Gram-negative bacteria, obligatory intracellular pathogen which is transmitted sexually and causes urethritis, cervicitis and adnexitis.

Endometriotic ovarian cyst formed by menstrual looking liquid, dense, like chocolate. They are always benign, have a high relapse rate and are treated with contraceptives, GnRH analogues or surgery.

An accumulation of bile acids in the liver and then in the blood, causing jaundice and generalised pruritus. Can occur during pregnancy, and maternal - foetal complications and tends to recur in subsequent pregnancies. It seems to be due to a toxic effect of the pregnancy hormones on the liver.

Inflammation of the foetal covering usually produced by bacteria in the vagina, which will cause uterine contractions or premature rupture of membranes.

Malignant ovarian tumour producing the pregnancy hormone (HCG). Very rare and aggressive tumour derived from the placenta, which appears after a pregnancy or occasionally after an abortion.

Outer membrane that covers the foetus and is connected to the uterus.

Taking a sample for cytogenetic chorion and fetal karyotyping. Can be performed transcervically or transabdominally.Being an invasive technique, it is associated with a risk of foetal loss estimated at 1%.

Small structural formations that are rod-shaped carriers of genetic information, i.e. information encoded in DNA. Each species has a constant number which are divided in the same way in each cell division or mitosis. Its graphical presentation is homologous pairs ordered by karyotyping.

Pregnancy with a heartbeat present in the observed embryo seen by ultrasound.

Surgical excision of the clitoris.

structure homologous to the penis located on the front of the labia minora, 2-3 cm long, consisting of two corpora cavernosa and glans and of erectile tissue.

Synthetic preparation which increases gonadotropin secretion. It is used to induce gametogenesis and ovulation and has a mild anti-oestrogenic effect.

obtaining in the laboratory a cell line with the same genotype or an individual identical to the original.

thick, yellowish discharge secreted by the breast at the end of pregnancy and during the first days postpartum, which has fewersugars but a higher concentration of protein, minerals and immunoglobulins than in breast milk.

Surgical removal of the vagina.

Surgical suture of the vagina in order to obliterate light.

Surgical repair and reinforcement of the pelvic floor muscles.

Suture of vaginal tear or reconstruction of the walls of the vagina.

Enlarged display of the vaginal mucosa and cervix with a colposcope or low magnification optical system.

intravaginal applicator containing a radioactive element that is used for the treatment of some gynaecological cancers (vaginal or cervical carcinoma).

Incision of the vaginal wall.

Mammary carcinoma which fills the ducts with necrotic material.

Warty growth that appears in the genital and perianal area, secondary to a sexually transmitted infection caused by HPV types 6 and 11.

Alteration, anomaly or defect that occurs in the embryonic stage or pregnancy and therefore will be present from birth.

Structural defect rooted at the prenatal stage.

Surgery to remove part of the uterine cervix in a cone shape, which serves as the diagnosis and treatment of premalignant lesions of the uterine cervix.

A group of drugs, devices, methods or surgical procedures that are intended to reduce the likelihood or prevent conception.

The element that prevents conception. It can be a barrier (condom), intrauterine device (IUD), hormonal (anovulatory), chemical (spermicides), surgery (vasectomy, tubal ligation, Essure).

Percutaneous puncture of the umbilical cord in order to obtain foetal blood for analysis or for intrauterine fetal transfusion.

Part of the cell that contains genetic information or DNA.

Structure where the ovarian follicle transforms after ovulation, responsible for the production of progesterone and the maintenance of the endometrium for embryo implantation. If no nesting takes place, there is atresia and it disappears.

Individual parts of the placenta in its maternal side, which is composed of about 15 to 20 cotyledons.

Local destructive freezing treatment applied to vulvar, vaginal or cervical lesions.

Freezing technique used on any tissue in liquid nitrogen at - 196 º. Can be used to store semen samples, oocytes, embryos, ovarian cortex, testicular biopsies, etc.

existing aspiration of fluid in the pelvis through a needle puncture in the back of the vagina.

Visual inspection of the uterus, ovaries and fallopian tubes through an optical system which is inserted into the pelvis through the posterior wall of the vagina.

Mass of cells surrounding the oocyte in the follicle, which are released with it after ovulation.

The time period that limits an event. For example, an IVF cycle, which begins around menstruation and ends with the transfer of embryos.

A malignant tumour derived from glandular epithelium, forming cystic cavities with fluid secretions with solid areas and usually occurs in the ovary.

A benign tumour composed of a large cyst arising from the ovarian epithelium with glandular secretions inside.

Prolapse of the bladder into the vagina due to a weakening of the muscles supporting the pelvic floor. Most frequently occurs at menopause and multiparous patients.

Microscopic examination of sloughed cells of an organ.Generally used for the study of vaginal and cervical epithelium.

DNA virus of the herpes virus family, which can affect pregnant women and produce various foetal problems, sometimes serious and irreversible, with significant consequences.

Drug used as a suppressor of anterior pituitary function, producing a hypoestrogonism and hence its use in endometriosis.Has many side effects, mostly due to increased androgens, which has now reduced its use.

Innermost layer of the pregnant uterus which has been thickened and vascularised to enable and promote embryo implantation.

Changes occurring in tissues that will allow embryo implantation in the uterus.

Tubes that connect the testes with the urethra to permit the release of sperm. Its ligation represents a vasectomy.

Decreased or delayed development. Intrauterine growth delay: when the birth weight is less than 10 percentile for gestational age.

hormonal preparation applied usually in the muscle or subcutaneous fat, which allows for gradual and prolonged release

A systemic disease of the metabolism of carbohydrates, characterised by the appearance of hyperglycemia caused by decreased secretion or insulin activity.

Lack of a proper relationship between the diameters of the foetal head and the maternal pelvis, causing a parked delivery

Deoxyribonucleic acid contains all the genetic information of a person organized in a double helix formed by nucleic acids.

Women between 18 and 35 years with an altruistic and anonymous will do a controlled ovarian stimulation treatment and extraction of her eggs to be donated to a recipient that needs to gestate.

Adult persons without hereditary diseases, infectious personal or that of an altruistic and anonymous will donate their gametes for others in need.

male between 18 and 35 years with an optimal semen, who selflessly and anonymously will freeze and donate their semen samples obtained by masturbation, for later use in a cycle of artificial insemination or IVF.

Tumour-derived ovarian germinal epithelium, which is rare and appears in younger patients (20 - 30 years).

Cyclic pelvic pain associated with menstruation. It may be idiopathic, due to the contraction of uterine muscle fibres, or secondary to organic pathology such as endometriosis, adenomyosis, uterine fibroids, etc.

Pain with intercourse. It may be superficial, usually due to lack of lubrication or vaginal stenosis, or deep, associated pathology such as endometriosis.

preneoplastic development of a tissue or organ. A level of the cervical epithelium is the precursor lesion to cervical cancer and is associated with human papillomavirus (HPV).

Difficult labor progress due to abnormal maternal (uterine contractility, pelvis) or fetal (size, malposition, malformation).

Seizures in a pregnant or postpartum woman whic usually represents the onset of gestosis. May be complicated by acute pulmonary edema, retinal detachment, foetal death in utero and even maternal death.

outer portion of the uterine cervix extending into the lumen of the vagina.

Implantation of the embryo outside the endometrial cavity. Its most common form is when the embryo is implanted in the fallopian tube, but can occur in the ovary, abdominal cavity or cervix. The embryo will never be viable and at the same time runs the risk of causing a rupture of the tube with internal bleeding and risk of serious maternal complications. Also called tubal pregnancy.

assisted reproductive technology, fully regulated by law, in which an anonymous donor and altruistically is donating her eggs to a recipient, with a condition that prevents or hinders gestate their own oocytes, and that may well go to see their desire to be a mother.

Patients without ovarian activity or decrease in its reserve, whose only possibility of gestating would be through an anonymous egg donor. She would only be required a functional uterus.

An organism in its earliest stage of development, considered from conception to the ninth week of gestation in humans.

Preparation of one or two cells in an 8-cell embryo (day 3) for analysis and genetic study in the course of a cycle of preimplantation diagnosis.

A laboratory technique associated with IVF which allows the observation of the development of embryos for selection and transfer.

A process in which good-quality surplus embryos are stored in cycles of IVF or egg donation.

Surgical technique for the removal of one or more embryos in multiple pregnancies, with the aim of reducing risks, especially prematurity, and improve the prognosis of the remaining embryos. It is not without risks and is associated with a 10% chance of miscarriage.

A part of the IVF process during which embryos are deposited through a thin plastic catheter into the uterine cavity.

In vitro fertilisation laboratory specialist, responsible for the micromanipulation of gametes and embryos and the evaluation of the latter until its transfer to the womb.

The process that physiologically occurs in the fallopian tube and can be seen in the laboratory in the course of an IVF cycle. Allows you to select the best embryos for transfer to the uterus.

Any abnormal condition of the embryo, morphological or genetic.

Defective closure of the foetal skull and causes a protrusion of part of brain tissue.

Inflammation of the endocervix.

Interior portion of the uterine cervix which continues into the endometrial cavity.

Taking a sample of endometrial tissue that lines the inner uterine surface, for histological analysis and functional morphology.

Benign cyst, single or multiple, unilateral or bilateral, which occurs in the context of endometriosis in the ovaries and which resembles thick chocolate (chocolate cysts).

Benign chronic disease characterised by the appearance of tissue hystologically and functionally similar to the endometrium outside the uterine cavity. It usually affects the pelvic organs, especially the ovaries and is usually associated with infertility, dysmenorrhea, pelvic pain and dyspareunia, although the symptoms are very variable.

Inflammation of the endometrium, usually secondary to infection. May be associated with implantation failure and IVF.

Glandular epithelial mucosa lining the uterine cavity and has the ability to shed and regenerate cyclically in response to ovarian hormones.

Mucous membrane that lines the inside of the fallopian tubes and is in charge of transport and sustenance of the embryo on its way to the uterus for implantation, 5 days after fertilisation and blastocyst stage.

Herniation of intestinal loops through the Douglas pouch and protrudes through the vaginal fundus. It is more common in multiparous patients with weakness or musculofascial.

Abdominal pains and contractions after birth and usually associated with multiparity and breastfeeding, reflecting the return of the uterus to its pre-pregnancy size.

coiled tube about 20 metres long, attached to the rear edge of the testis, is continuous with the vas deferens and is responsible for collecting the sperm developed in the seminiferous tubules. It will acquire sperm mobility.

Surgical repair of episiotomy and perineal lacerations after delivery.

Reconstruction vulva defects after episiotomy.

Incision of the perineum to allow greater and safer vulvar expansion, to avoid tears with the output of the foetal head and shortens the time of delivery. There are three types: medial, mediolateral and lateral.

Incision of the perineum to allow greater and safer vulvar expansion, to avoid tears with the output of the foetal head and shortens the time of delivery. There are three types: medial, mediolateral and lateral.

Benign tumour of the gums that occurs during pregnancy due to the effect of the hormones of pregnancy and disappears after delivery.

Benign tumour of the gums that occurs during pregnancy due to the effect of the hormones of pregnancy and disappears after delivery.

Main oestrogenic hormone produced in the ovary and placenta, prepares the endometrium for implantation for the fertilised egg. It is also essential for proper development and functioning of the female reproductive organs.

The most abundant oestrogen hormone but relatively weak. It is used in topical preparations such as local trophic vulvovaginal.

Principal oestrogen hormone in menopausal women, resulting from peripheral conversion in the subcutaneous tissue of androstenedione.

A synthetic form of estradiol that most power is used in small doses in most oral contraceptives.

A cell that contains the correct number of chromosomes. In humans, 23 pairs.

Postoperative complication involving the output of the intestine through the incision.

Ducts that communicate the uterus to the ovaries. Formed by 3 segments: isthmus- which connects it to the uterus; blister and infundibulum, which contain the fimbriae that catch the egg during ovulation. Fertilization occurs here, followed by the transport of the embryo to the uterus (which takes 5 days) in the phase of blastocyst in order for implantation to happen.

Specialist in Gynaecology and Obstetrics, who is specifically devoted to the study and treatment of problems associated with human reproduction.

A set of signs that reflect the fetal response to stress caused by a disease in utero or intrapartum.

Technique to study the expression of cellular molecules, which is used for diagnosis and monitoring of various diseases. Assisted reproduction is used to separate X from Y sperm, for the purpose of sex selection.

Decreased foetal heart rate below 120 beats per minute during a period of 15 minutes. Difficulties generally associated with foetal adaptation to the intrauterine environment or reduction of foetal wellbeing.

Relationship between the foetal longitudinal axis and the maternal longitudinal axis. Longitudinal Position: both axes are almost parallel, which occurs in 99% of pregnancies to term. Oblique Position: the angle between the two axes is about 45 °. At birth, it often becomes a longitudinal or transverse position. Transverse Position: both axes determine an angle of approximately 90 °.

Intolerance to carbohydrates detected by a glucose tolerance test. It starts during pregnancy, usually after the third quarter, and is an effect of pregnancy hormones and may be associated with foetal macrosomia.

A molecule that displaces the natural GnRH for its receptor leading to a blockage of the hypothalamus - pituitary.

synthetic molecule similar to GnRH secreted by the hypothalamus and essential to assisted reproduction techniques.

A molecule that directly inhibits the action of GnRH on its receptor, blocking the hypothalamus - pituitary system more quickly.

Top of the uterus where the fallopian tubes begin.

Inability to conceive after regular exposure to intercourse for 1 year. It affects about 15% of couples. The cause is male in 40% of cases, another 40% female and mixed in the remaining 20%.

contraceptive method consists of a plastic that is inserted into the uterine cavity. They have different shapes (anchor, T) and usually have copper or progesterone to achieve the desired effect.

Chromosome make-up of an individual. The human species consists of 22 pairs of autosomes and 2 sex chromosomes. Women are 46 XX and men 46 XY.

Cervical epithelial cells with a perinuclear halo secondary type to infection with human papilloma virus (HPV).

A professional in charge of tasks and procedures in a laboratory such as analysis, seminal studies, hormonal studies etc.

Abnormally large head circumference in a child. May be associated with hydrocephalus, trauma, or be idiopathic

Abnormally large newborn, such as those born to pregnant women with diabetes with poor metabolic control. This is associated with an increased number of caesarean sections, neonatal disorders of homeostasis and increased risk of foetal trauma during vaginal delivery (brachial plexus injuries).

Primary structural defect of a body part resulting from a localised error in development. It may be congenital or acquired.

Radiological imaging for detection of breast tumours.

It may be reconstructive (after surgery), augmentation (implants) or reduction.

Feature by which a cell or a molecule can be identified or a disease diagnosed.

Surgical removal of the breast due to cancer.

Inflammation of secondary breast tissue due to a bacterial infection. Bacteria passes through the nipple, and is more frequent during breast-feeding.

Pain in the breast. Also called mastalgia.

Refers to any disease of the breast.

The process by which a primitive cell reaches its final structure and functional capacity (human egg).

External opening in the body (urinary meatus).

Dark green intestinal content formed before birth and present in the ileum from days 75-80 of pregnancy. It is composed of intestinal epithelial cells, skin cells and fetal hair (lanugo) swallowed by the fetus together with amniotic fluid.

Synthetic progesterone used as a progestin.

Abnormally large colon. It can be congenital or Hirschsprung's disease due to the absence of nerve cells in the junction between the rectum and colon. The aganglionic area of the bowel cannot relax during bowel movements leading to constipation and colonic distention. In newborns, symptoms include abdominal distention, failure to pass meconium and vomiting bile.

Synthetic antineoplastic drug with progestogenic effect.

Areas of dark patches on the skin, most commonly on the face and neck caused by the action of oestrogen, for example through the use of hormonal contraceptives and pregnancy. It is also called chloasma.

First menstrual period, usually occurs between ages 12 and 13.

Uterine bleeding occurring at irregular intervals and vary in the amount and duration of flow.

Female stage of life which marks the transition of childbearing years to the non-reproductive period. It is characterised by the onset of climacteric symptoms (hot flushes, night sweats, irritability, insomnia, vaginal dryness, etc).

The permanent cessation of menstruation due to ovarian follicular depletion, characterised by a climacteric and its consequences. Occurs naturally around age 50.

Excessive and prolonged menstrual flow. May be due to functional or organic pathology (polyps, submucous myomas).

A period usually of 28 - 35 days in which oocytes are recruited, one is selected, which then matures and is released during ovulation to be caught by the tubal fimbriae and could then be fertilised by sperm. This fertilised egg becomes an embryo and moves along the fallopian tube so that on Day 5 of postfecundation and inblastocyst stage, it can nest in the endometrial cavity. If implantation takes place, the production of the pregnancy hormone starts and if it does not occur the endometrium is shed forming menstruation.

The cyclic shedding of the endometrial lining in the absence of pregnancy, usually at intervals of 28-30 days and lasting 3-5 days.

Synthetic estrogen ethinyl estradiol derivative used in hormonal contraceptives.

An abnormality in cell differentiation, in which an adult cell type is replaced by a different type of mature cell that is not normal in that tissue. Squamous metaplasia: transformation of columnar epithelium stratified squamous epithelium that frequently occurs in the endocervix.

Malignant tumor cells found in different areas than the original or primary tumour. The ability to metastasise differentiates benign from malignant tumours.

Cancer treatment drug, besides being used in the treatment of certain neoplasms (choriocarcinoma, lymphoma) it is used for autoimmune diseases (rheumatoid arthritis, ulcerative colitis) and in medical treatment of ectopic pregnancy as well. Can be used orally or through injection.

An antibiotic used to treat infections caused by anaerobic bacteria and protozoa.

Any pathological process that occurs in the uterus.

Uterine bleeding at irregular intervals. May be due to infectious diseases, cancer, etc.

Drug used to treat fungal infections, mainly for vulvovaginal candidiasis. Can be used as vaginal suppositories, cream and gel.

Decrease in the size of the head due to reduced brain mass. Usually associated with congenital syndromes (trisomy 13), infections (CMV) and central nervous system malformations.

Local extension of a cancerous tumour to a depth no greater than 3 mm in adjacent tissue in the absence of lymphatic invasion or blood.

Progesterone antagonist used to induce early abortions. Its trade name is RU-486.

Contraceptive pill contains only progesterone in low doses. Induces anovulation and amenorrhea continued. It is generally used as a contraceptive of choice in infancy or when oestrogens are contraindicated.

Expulsion or extraction of the product of conception before 20 weeks of pregnancy or with a weight of less than 500 grams. Threatened miscarriage is the bleeding of the uterine cavity in a pregnant patient. Miscarriage in progress when the cervix is dilated and there are contractions. Incomplete miscarriage involves partial removal of the pregnancy. Complete miscarriage when the product of conception is entirely extracted. Missed miscarriage when no bleeding occurs but there is no heartbeat. Spontaneous miscarriage is when pregnancy loss occurs without any medical intervention. Therapeutic miscarriage is when pregnancy is interrupted by foetal or maternal problems. Biochemical miscarriage is one in which there is pregnancy hormone production (B-HCG) but without the gestational sac forming. Clinical miscarriage is a miscarriage that occurs after or at the same time that it is seen on ultrasound.

Abnormal pregnancy in which a clear mass that resembles a bunch of grapes grows in the womb due to the proliferation of placental tissue. It may be complete or partial, depending on whether there an embryo is present. Also called a molar pregnancy or gestational trophoblastic disease.

Synonymous with candidiasis.

Monitoring and continuous monitoring for patients considered at risk or who are undergowing specific treatments, such as ovarian stimulation in an IVF cycle.

Twin pregnancy with a single amniotic sac containing two foetuses.

Chromosomal abnormality in which a chromosome is lost and therefore the karyotype is 45 instead of 46. It can affect any chromosome and is incompatible with life except Turner syndrome or 45 X0.

Twin pregnancy originated from a single embryo. The two foetuses share their genetic identity and are of the same sex. They generally share the same placenta and amniotic sac itself.

Proportion of people falling ill in one place for a period of time compared to total population there.

Total number of deaths in a given period of time in a population.

Solid spherical mass of cells from the division of the fertilised egg in the early stages of embryonic development. It represents an intermediate stage between the zygote and blastocyst and is composed of blastomeres and uniform in size, shape and physiological potential.

The presence of two or more populations of cells in a person, some with abnormal number of chromosomes and others with extra chromosomes or deficit. Caused by errors in the division of the fertilised egg. The presence of abnormal cells increases the risk of miscarriage and chromosomal syndromes.

Inner layer of a tubular cavity (oral, esophageal, vaginal ...).

Women who have been pregnant more than once.

A woman who has completed two or more pregnancies in each of which the foetus has reached viability, whether born alive or not.

Introduction of two or more embryos into the endometrial cavity. Most are secondary to assisted reproductive techniques and will be accompanied by more maternal complications (hypertension, diabetes, etc) and foetal (prematurity, low birthweight, sequels, etc.).

Permanent and heritable structural change in the DNA.

Single-celled microorganism that lacks cell membrane and can cause various diseases such as pneumonia and infections of the genital tract.

(Spina bifida) A neural tube defect with protrusion of the membranes covering the spinal cord through an abnormal hole in the vertebral column. The protrusion is covered with skin and contains spinal cord tissue and nerve roots.

Suppression of the activity of hematopoietic stem cells from bone marrow, responsible for the production of red cells, white cells and platelets.

A benign tumour composed of smooth muscle cells and collagen. It usually occurs in the uterus, may be single or multiple and can occur anywhere on the uterine wall. Also called fibroid or leiomyoma. They are classified into subserosal, intramural and submucosal.

Surgical removal of fibroids. The subserosal and intramural may be removed by laparotomy or laparoscopy, whereas submucosal treated with hysteroscopy.

Muscular middle layer of uterine wall composed of smooth muscle fibres arranged in three layers: the outer which continues through the fallopian tubes, the round utero-ovarian ligament and, the intermediate, which is the thickest, contains large venous vessels and is in contact with the endometrium.

An IVF treatment in which ovulation is not stimulated with exogenous hormones and therefore only one egg will be recovered per attempt. The cost of the procedure is very low.

Vomiting, usually associated with the first trimester of pregnancy.

Depressed area in the abdominal wall where the umbilical cord links to the foetus.

Irreversible damage and cell death in a specific area of living tissue and organs.

Absence of motile sperm in a sperm sample.

The first four week period of life of the newborn.

The branch of medicine concerning alterations of the newborn from birth to the first 28 days of life.

Abnormal process results in the formation and growth of a tumour.

Surgically constructed vagina using skin from another area of the body or a piece of intestine and is made after the total removal of the pelvic organs in the treatment of advanced cancer or congenital absence of a vagina.

Kidney disease that primarily affect the tubules.

Surgical opening of the renal pelvis to insert an external drain.

Toxic to kidney cells and kidney function.

Newborn from birth to 28 days of life.

Adding packed cells that appear different from the surrounding tissue.

Progestogen use associated with oral contraceptives and estrogen replacement therapy, used alone in the treatment of endometriosis and amenorrhea.

Women who have never been pregnant.

A woman who has never given birth after 20 gestational weeks or of 500 grams.

Synonym of the labia minora, closing the introitus.

Excessive accumulation of body fat. It is associated with increased risk of morphological abnormalities and miscarriage in pregnant women and decreases the success of assisted reproduction techniques. It is determined via the body mass index (BMI = weight / height squared).

A doctor specialising in obstetrics.

The branch of medicine that is primarily responsible for the monitoring of pregnancy, labour and birth.

Blockage passing through a tubular structure (vein, artery, etc.). Tubal obstruction causing sterility.

Closure of a tubular structure, for example, tubal ligation as a permanent contraceptive method.

A general term for the female sex hormone responsible for stimulating and maintaining secondary sexual characteristics, synthesised in the ovaries, placenta, testes, adrenal cortex and some vegetables such as soy (phytoestrogens).

Ovarian hyperstimulation syndrome. Complication of assisted reproduction techniques, potentially serious and even fatal, characterized by vascular leakage of fluid to a third space, resulting in ascites, pleural and metabolic disorders.
It does not occur if there is no exogenous HCG administration and at the same time it tends to get worse if there is a pregnancy and high endogenous production of HCG.

Amniotic fluid deficiency, may be due to premature rupture of membranes, foetal urinary tract obstruction, intrauterine growth retardation or foetal death. Also called oligohydramnios.

Reduction in the frequency of menstrual periods or menses each over 35 days.

Decreased number of sperm per unit volume. It is considered when <20 million sperm / mliappears in the ejaculate .

Congenital hernia of the navel in which a small portion of the abdominal contents covered by a membranous sac protruding into the base of the umbilical cord. Often associated with chromosomal abnormalities.

Specialty of medicine that deals with the study of the causes, characteristics, diagnosis and treatment of cancer.

An accumulation of various fluids inside the ovary (serum, mucin, pus, fat, etc.). They are usually benign and treated by laparoscopic surgery.

Urine analysis that seeks to detect the LH peak in order to determine the woman's most fertile period.

Removal of the pelvic organs in the treatment of advanced or recurrent pelvic cancer. It may include the bladder, urethra, uterus, ovaries, fallopian tubes, vagina, and lymph nodes to the rectum-sigma.

Inflammation of the female internal genital tract, secondary to a sexually transmitted infection or other vaginal bacteria. Usually is associated with pelvic pain and fever, will require antibiotic-anti-inflammatory treatment, and can badly affect the tubes which are then associated with infertility or ectopic pregnancy.

Anatomical area bound between the pelvis and diaphragm, covered by the peritoneum and which contains all the abdominal and female pelvic organs.

Preimplantation genetic diagnosis involves the detection of a disease in a blastomere prior to the transfer of healthy embryos to the womb. Requires a cycle of IVF, an embryo biopsy and genetic analysis.

Pre-implantation genetic screening used for the study of aneuploidy in embryos generated after an IVF cycle. It might be indicated in patients with repeated abortions, advanced maternal age, repeated implantation failures and FISH in altered sperm.

Total or partial detachment of the placenta, resulting in genital bleeding during pregnancy, acute foetal distress, foetal death and coagulatory problems in the mother.

Status of women from conception until birth. It is usually 280 days from the date of the last menstruation. Also called gestation.

Introduction of a catheter into a cavity, a channel or a tubular structure.

Surgical technique for the treatment of breast cancer, removing the tumour and all breast tissue encompassed in that quadrant as a safety margin.

Emission and power projection of high-speed particles or waves

X-ray technique to determine the height, diameter and shape of the pelvis.

Medical specialist in radiotherapy.

Treatment of malignant disease with high-energy rays or subatomic particles such as alpha, beta and gamma rays; radioactive materials include cobalt, radio, cesium, and iridium.

Hernial protrusion of the rectum with posterior vaginal wall caused by alteration of the connective tissue between rectum and vagina, which weakens the wall and usually occurs after childbirth.

Portion of the intestinal tract that extends from the sigmoid colon to the anal canal.

Involuntary and immediate response to a stimulus.

Two or more miscarriages either consecutive or alternating with term pregnancies.

Two or more miscarriages either consecutive or alternating with term pregnancies.

The process of reproduce. Assisted reproduction: reproduction achieved through the help of certain techniques, including direct retrieve of ovarian oocytes and transfer of gametes and embryos into the uterus.

Surgical removal of tissue or body parts.

Maintain corporal wastes that are abnormally discharged (retained placenta).

Behind the mammary glands (breast retromammary prosthesis).

Behind the first portion of the large intestine (cecum) in the right lower abdomen.

Located behind the cervix.

Organ rack back. Uterine retroflection: extreme inclination or angulation backwards to the uterine body, while the cervix remains in its normal position without any functional repercussion and associated with dysmenorrhoea.

Movement around an inner axis. In obstetrics, the rotation of the head or the foetal presentation at birth, so that the head fits into the birth canal.

Contagious viral disease, usually mild and of short duration, but capable of causing foetal abnormalities if the mother has the infection during the first three months of pregnancy (rubella embryopathy). It is characterized by malaise, fever, enlarged lymph nodes and maculopapular rash. Caused by the rubella virus "rubivirus" gender. The incubation period is 2 to 3 weeks. Currently virtually eradicated by vaccination at 12-15 months and 3-4 years.

Anatomical structure in a pouch. Gestational sac: membranes enveloping the foetus or embryo. Composed by the fusion of chorion and amnion.

Gently curved, triangular bone, composed by 5 fused vertebrae forming the back of the pelvis. It gets articulated with the ileum of each side, the tail bone down and the last lumbar vertebra above.

In anteroposterior position.

Surgical removal of the fallopian tube, usually by laparoscopy

Inflammation of one or both fallopian tubes. It can be caused by infection with a single or several bodies. The most frequently implicated include Neisseria gonorrhoea, Chlamydia trachomatis and Ureaplasma urealyticum.
It is associated with tubal-factor infertility.

Surgical removal of the tube and ipsilateral ovary.

Radiographic examination of the fallopian tubes after infusion of radiopaque contrast through the cervix, usually done to diagnose tubal obstruction.

Surgical repair of the fallopian tube. Poor results technique and displaced by IVF.

Surgical linear opening of the tube when there is an ectopic pregnancy. It is carried out to preserve the tube and try to maintain its function.

Tube in Latin.

Cancerous tumour composed by connective tissue

Any structure, lesion, mass or radiographic density associated to another, usually larger, one.

Digitised, radiological device which systematically scans a given anatomical area, point by point.

Digitised, radiological device which systematically scans a given anatomical area, point by point.

Hardening of the tissues by proliferation of connective tissue. Usually associated with chronic inflammations.

Hardening of the tissues by proliferation of connective tissue. Usually associated with chronic inflammations.

Review of a large population to detect a particular disease or disorder.

The process by which a cell or gland produces and releases a substance.

Women who have given birth twice.

Surgical treatment aimed at removing one or several embryos in supernumerary pregnancies after assisted reproduction techniques. It is performed vaginally (8-9 weeks) or trans-abdominally (12-14 weeks) under sedation. It is not out of risk. The highest risk would be the abortion of all embryos.

Depression between two ridges (anterior and posterior) of the uppermost surface of the sphenoid bone at the base of the skull that resembles a Turkish sword. It houses the pituitary gland.

secretion produced by the testicles and the accessory glands containing sperm, plus glandular products of secretion. Together they form the seminal fluid. Synonym of sperm.

A group of small tubules found in the interior of the testes where sperm is produced.

systematic response to infection characterized by two or more of the following signs: elevation of body temperature, heart and respiratory rate and white blood cell count.

Thin wall or split between two cavities or masses of thin tissue. Uterine septum: most frequent uterine morphological abnormality, secondary to a defect in caudo-cranial re-absorption of the fused Mullerian conducts, that is associated with repeated abortions. It is treated by hysteroscopic septoplasty.

Attached by a broad base instead of a pedicle; applied to polyps and tumours.

Attached by a broad base instead of a pedicle; applied to polyps and tumours.

Molecular medical procedure that allows the choosing of the sex of the baby. The patient has to undergo an IVF cycle with pre-implantation diagnosis. It might be indicated in case of sex-linked inherited diseases. In this case, the Spanish law supports it. But In case of sex "social" selection, most countries, including Spain, forbid it tacitly.

Applied to the distal descending colon portion.

Any objective indicative evidence of disease that is perceived by the examiner.

the upper front part of the head.

position for the foetal head to traverse the maternal pelvis at birth. The head fits into the pelvis with the sagittal suture in the transverse diameter of the maternal pelvis, midway between pubis and sacrum.

A mixture of a liquid, solid or gas (solute) substance and a non-crystalline liquid or solid (solvent) through which the dissolved substance can be recovered.

Synonymous for anechoic. It is used in an ultrasound to define an image occupied by liquid.

An instrument for dilating and keeping open a channel or cavity to facilitate inspection and acting on it (vaginal speculum).

Haploid cell of the testis, from secondary spermatocytes, which undergo the process of spermiogenesis to become spermatozoa.

Mature male gamete, contracted to transport the male haploid genetic load into the oocyte. It consists of head, midpiece and tail or flagellum that allows mobility. According to WHO criteria of normality are 2 ml, 20 million / ml, 50% of mobile type A + B, 14% of normal forms.

Storage unit for cryopreserved sperm samples from anonymous donors for subsequent use in fertility treatments in which sperm is needed

Any physical or chemical substance that kills sperm. It includes copper IUDs, and nonoxynol-9 in creams, condoms and vaginal sponges.

The study of quality in a semen sample of ejaculate. At least 2 semen samples are recommended in order to reach an accurate diagnosis. It envolves a macro and microscopic study of semen, along with the analysis of the number, motility, morphology, survival test, test selection, etc. in the spermatozoa.

Circular muscle that remains closed and open body cavity relaxation which allows the passage of substances through the cavity.

Circular muscle that remains closed and open body cavity relaxation which allows the passage of substances through the cavity.

A congenital defect closing level of the posterior arches of the spine that allows the protrusion of the membranes or even the neural canal.

Low and unexpected vaginal bleeding. It may be insignificant or it can indicate a functional or organic disorder.

Stage of any process or procedure, as the course of a disease.

clinical method for estimating the severity of a cancerous tumour, based on its size, local invasion and distant metastasis.

Gram-positive bacteria, stationary and tends to aggregate in clusters. The most common pathogens are Staphylococcus aureus and epidermidis.

Abnormal narrowing of a body cavity or canal. Cervical canal stenosis occurs absence of menstruation and cyclical abdominal pain.

Free of potentially pathogenic living microorganisms.

Destruction or removal of living organisms in any form. Treatment depriving a living on their ability to reproduce.

A family of chemicals with an identical biochemical basis. Including adrenal hormones, male and female sex.

The act of exciting the body or any part thereof to increase functional capacity.

Gram positive bacteria round or ovoid in pairs or chains.

A line or parallel lines on the skin caused by dilation and relaxation of elastic tissue. Often associated with obesity but mainly pregnancy.

Skeleton support of an organ.

Failure of an organ to get completely restored to its normal size. Like when the uterus remains abnormally increased in size after birth.

Production of a number of eggs larger than usual, normally resulting from administration of exogenous gonadotrophins in assisted fertilisation procedures.

Fertilisation of two or more eggs in a short period of time (during the same ovulatory cycle) but not necessarily in the same coitus, nor with the same man.

Medical specialty that deals with the treatment of disease, deformity and injury through manual or instrumental operations.

assisted reproduction technique that allows women without a uterus to get a child, either with her own eggs or even through egg donation. In most countries, including Spain, it is not legal. This technique is normally carried out in USA and India.

Treatment cycle is interrupted by a bad administration of medication.

Thread used in surgery to approximate surfaces. Immovable fibrous joint that connects the bones of the skull.

laboratory technique used to select and capacitate the sperm that will be used for insemination or IVF.

Type of joint where the opposing surfaces of bone are covered by a thin layer of hyaline cartilage and held together by a layer of fibrocartilage (pubis).

subjective disorders experienced by the patient that are examined by the physician. The medical treatment is based in the signs and the additional tests performed.

trophoblast peripheral zone. It enters into the maternal tissues to attach the blastocyst to the uterus and become part of the placenta.

A set of signs and / or symptoms that occur together with reasonable consistency. S.Hellp: haemolysis, elevated liver enzymes and low platelet count; it may occur in pregnant women in association with severe preeclampsia and eclampsia. Ovarian hyperstimulation S.: in assisted reproduction, ovarian volume increase, bloating and weight gain. Severe cases include ascites, pleural effusion, electrolyte abnormalities and hypovolemia with hypotension and reduced glomerular filtration.

An infectious disease caused by the Treponema pallidum bacterium, transmitted by sexual contact or other primary contact. The first symptoms appear after an incubation period of 12 to 30 days. The microorganism can cross the placenta and infect the foetus.

Abnormally fast heartbeat. Usually occurs when pulse exceeds 100 beats per minute. It may also be called tachyarrhythmia. Foetal tachycardia occurs when the foetus' pulse exceeds 160 beats per minute. It tends to be caused by a maternal infection, foetal hypoxia or the consumption of certain substances by the mother.

Rapid decreasing response to a physiological or pharmalogically active substance after its repeated administration.

Abnormally rapid breathing

The commercial name for Placlitaxel. A drug used in chemotherapy, derived from yew bark, used in cancers such as ovarian, breast, lung etc.

The packaging around an ovarian follicle composed of an external fibrous layer and an internal vascular and secretor layer.

Laceration occurring during vaginal birth and can affect everything from the vulvar skin to the rectal mucosa.

Ovarian tumour, solid and benign composed of teak cells with varying degrees of lipid content.

Abnormal dilation of groups of thin veins in the skin or in mucous membranes.

Beginning of breast development in adolescent women.

Any environmental agent or microorganism which is able to produce physical defects in the embryonic or foetal development.

Tumours that derive of one of the three layers of germ cells (endoderm, mesoderm or ectoderm). They are continually seen in ovaries and testes. They can be benign or malignant and can occur at any age.

Number of sperm with normal morphology less than 14%.

Glands that produce sperm and hormones (testosterone and small amounts of estrogen), normally found in the scrotum.

Sampling of testicular tissue under local or general anaesthesia for diagnostic study or to retrieve testicular sperm, which can be used for one cycle of IVF - ICSI or frozen for future use.

The most powerful male hormone responsible for the development and maintenance of the secondary sexual characters. It is produced by testicular Leydig cells under the control of the pituitary luteinizing hormone.

A group of hereditary alterations characterized by the deficient production of one of the polypeptide chains of hemoglobin. It is classified in function of: if the affected chain is Alpha or Beta, and the latter in major or minor, in function of the penetrance.

A hypnotic drug and sedative that can produce fetal anomalies if they are taken during pregnancy. Characteristically, they produce phocomelia.

A decreased number of platelets in the blood (less than 150.000 per microlitre).

The inflammation of the wall of a vein in association with the formation of a clot.

An abnormal vascular situation in which a thrombus develops in the inside of a blood vessel, both in arteries and veins.

Blood clot. A solid or semi-solid mass formed in the inside of an intact blood vessel. It is composed of the constituents of blood, mainly platelets and fibrin.

A state of secondary blood hypercoagulability to a deficit of the natural inhibitors of coagulation such as the protein C, S and antithrombin III. It can be hereditary like the Factor V Leiden or Prothrombin 20210 and can be associated to repeated abortions or recurrent miscarriages.

Endocrine gland found in the neck, underneath and to the sides of the trachea, and the back of the larynx, where thyroid hormones are produced.

Autoimmune inflammation or affectation of the thyroid glands, which can cause hyper or hypothyroidism.

A hormone that is elaborated by the thyroid gland and is in charge of the regulation of the basal metabolism and development.

Mass of cells and of the surrounding substances which are united in order to carry out a particular function.

Inhibition of uterine contractions to stop the risk of preterm birth.

Chronic bacterial infections that occur during the perinatal period and cause similar clinical and laboratory findings. The term is an acronym for: Toxoplasma, Rubella, Cytomegalovirus and Herpes.

A twist or curl around an axis.

The presence of bacterial toxins in the bloodstream.

A disease caused by the infection of Protozoon Toxoplasma Gondi. It can give the symptoms of a common cold or an infectious mononucleosis in adults. The disseminated form can produce hepatic, pulmonary, cardiac, cerebral or spinal inflammation. Another form affects the eyes. A women infected during pregnancy can transmit the disease to her child, causing cerebral damage or even death. The most common form of acquiring the infection is by ingesting raw meat or being in contact with infected animal stool (cat).

The action conducted through the hole of the cervix.

Surgical and hormonal intervention to alter the external characteristics of an individual in order to make the person look of the opposite sex.

Current method of oocyte collection in in vitro fertilisation treatments.

Any course of action or program adopted to restore health, prevent illness or to mitigate symptoms.

Genus of parasites, Flagellates. Trichomona vaginalis: A mobile form that infects the lower genital tract in women, as well as the urethra and the prostate in men.

The infection of the lower genital tract with Trichomona Vaginalis, practically always acquired by sexual transmission. In women, it usually causes various degrees of vulvovaginal irritation, pruritus and leucorrhea. Men tend to be asymptomatic.

An abnormality in which an additional chromosome is present in cells. The extra chromosome is a copy of an already existing pair, so that particular chromosome is triploid. The consequences can go from early fetal death or abortion to numerous abnormalities in the newborn.

External layer of cells that form the wall of the blastocyst. Plays an important role in embryonic nesting and later goes to form the placenta.

Excessive tissue growth. If it is malignant, it is called neoplasia.

A visualisation of the body's internal structures by applying high frequency sound waves to the body tissues and converting the echoes into an image on a screen. It is the basis of current Gynaecology and Obstetrics.

Sound waves with a higher frequency than the range which is audible by humans. They are propagated at a certain speed in function of the physical conditions of the medium through which they pass.

Safe technique of modern obstetrics and gynecology, based on the piezoelectric effect. Currently composed of several variants such as 2D, 3D, 4D, Doppler, colour Doppler, etc.

A channel present in the foetus between the navel and the apex of the bladder. It is obliterated in Utero and becomes a thick fibrous cord after birth.

A genera of gram-negative bacteria that lack cell walls and hydrolyse urea. Ureaplasma Urealyticum: Responsible for genitourinary infections, which are often transmitted sexually.

A long and thin muscular tube that carries urine from the renal pelvis to the bladder.

Abouchement of the distal ureter to skin of the lower abdomen and maceration of external opening through which urine can be discharged when the bladder has been removed.

Surgical division of the ureter.

A channel that carries urine from the bladder to the exterior of the body.

Inflammation of the urethra. Common symptoms are burning sensations during urination. It is usually caused by infections or chemical irritation.

Surgery for the treatment of stress urinary incontinence. It surgically elevates the bladder neck.

Pain or discomfort during urination.

The study of the activities of the bladder, the urethral sphincter and the pelvic muscles with the use of various pressure mechanisms.

Visualisation (using X rays) of the urinary tract.

The reconstructive surgery of the uterus.

A deep muscular organ in women found in the pelvis between the bladder and the rectum. Its function is to host the embryo and the foetus until birth. It has the shape of a pear, a thick wall and is approximately 75 mm long. It reaches adult size at the age of 15 and reduces in size at menopause. It consists of a main section, a superior section which ends in the Fallopian tubes, and another lower section which opens to the vagina: the neck.

A musculomembranous structure in women, which extends from the cervix to the vulva.

Involuntary contractions of the musculature that surrounds the vagina which hinder or prevent penetration. This can be a cause of sterility.

The inflammation of the vagina due to an infectious, traumatic or unspecified factor.

The reconstructive surgery of the vagina. It may also be called colpoplasty.

Vaginal infection due to an increase of anaerobic bacteria which are part of the usual flora of the vagina.

Tortuous dilated veins due to an alteration in their valves.

Relative to sexual contact.

A branch of medicine that is in charge of the study of STDs.

Abnormal state of expansion of a cerebral ventricle, like the one seen in hydrocephalus.

A manual turn of the foetus in the uterus to change its position and make it more favourable for labour.

A small elevation of the skin, usually product of the human papilloma virus.

Portraying an image of inside the body using X-ray transmission through it with a thin layer.

A layer of glycoprotein around a developing ovule in an ovarian follicle. It plays a role in fertilisation when it is penetrated by the sperm. It persists when the zygote is dividing until the stage of a blast cyst. This is when it degenerates and disappears just before the process of implantation.

A fertilised cell structure produced by the union of masculine and feminine reproductive cells.