Instituto Bernabeu discovers fertility genetic variants

Following years of research, the Poor Responder Unit at Instituto Bernabeu has, for the first time, discovered the genes that play a role in ovarian reserve. This makes choosing the most appropriate medication for the patient’s genetic make-up possible, thus optimising ovarian response.


The endometrial receptivity array (ERA) test

Embryo implantation is the least well known phase of reproduction within the field of reproductive medicine. This fact is of special relevance if we also take into account that the human embryo is not very efficient when compared to other closely-related species in the evolution timeline.
We currently know that pregnancy is based upon three basic pillars: the embryo, the endometrium and the tolerance of the mother’s immune system. Not only is it essential that all three function correctly, but there needs to be optimum interaction between them. We have already covered the role of the embryo and the immune system in detail. Therefore, we will now concentrate on the endometrium and, more specifically, on studying endometrial receptivity. […]

Why does embryonic arrest sometimes happen during in vitro development?

Many factors can intervene in arrest processes during embryo development which mean cell division is detained and, therefore, it is not possible to implant the embryo in the mother’s uterus and bring about a pregnancy.
In the first instance, the conditions for development are essential.  Embryos that develop in vitro are subjected to a number of artificial conditions that do not exist in vivo and which will always be less than optimum. Embryos which were apparently viable can suffer embryonic arrest. Huge efforts have been made over the last few years to try and mimic what happens inside the mother and replicate those conditions in laboratory processes.  Most of all, the concentration of oxygen in incubators has been reduced, going from 20% down to 5%. The composition of the culture means has also been improved. This, along with exhaustive monitoring of pH and osmotic concentration, means that we can routinely carry out prolonged embryo development up to blastocyst stage in order to achieve improved embryo selection and increase pregnancy rates. […]

What is the significance of FSH hormone levels in fertility?

Follicle-stimulating hormone (FSH) is essential to reproduction. It is produced by the pituitary gland situated just below the brain (behind the palate) and is released into the bloodstream. The hormone regulates the ovaries and is involved in the processes dealing with the growth and selection of the follicle which will later release the egg during ovulation.
Fluctuations in FSH levels are responsible for menstrual cycles and also for the fact that only one egg is produced during each cycle. It is essential, therefore, that there is constant dialogue between the ovaries and the pituitary gland so that the latter can consistently produce the correct quantity of FSH for a normal cycle.
This permanent exchange means that, in cases of poor ovarian function, the pituitary gland will try to compensate for this situation by increasing FSH excretion levels. It is for this reason that FSH levels in women going through the menopause are 20 times greater than in women whose ovaries are functioning normally. Therefore, when the ovary does not respond correctly, FSH increases significantly and systematically. […]

Embryo transfer on day 3 or day 5. The pros and cons.

Determining the ideal day for embryo transfer has always been a controversial issue and there are, even today, still a number of doubts surrounding this issue.
Embryo culture is, basically, a selection process. Each embryo’s progress is evaluated throughout and a decision is taken on which is most likely to implant successfully. […]

Recurrent pregnancy loss: an issue that does have a solution

Clearly one of the most difficult situations a couple trying for children may have to face is pregnancy loss. Suffering is even greater when, prior to this, the couple has gone through fertility treatment such as in vitro fertilisation, insemination or egg donation.
Pregnancy loss is not always the result of an illness or underlying abnormality. It can be the response nature provides in order to block the development of an abnormal embryo. In fact, when the tissue from the pregnancy loss is examined, a large number of chromosomal abnormalities can be detected. […]

State of the art technology in preimplantation embryo diagnosis: Array-CGH

Preimplantation Genetic Diagnosis (PGD) is the study of chromosomal and genetic abnormalities in embryos before they are transferred to the mother’s uterus by an In Vitro Fertilisation (IVF) technique. It seeks to ensure healthy offspring and stop transmission of a given disease. […]

Co-mother registration for lesbian couples

Last July, Act 19/2015 on administrative reforms in the field of Justice Administration and Civil Registration made changes to article 7.3 of Act 14/2006 on human assisted reproduction techniques, making it clearer than before and providing for equality between heterosexual and lesbian couples.
The new law states that ‘When a woman is married to another woman and there has been no legal or de facto separation, the latter, in accordance with the Law on Civil Registry, may agree to her parentage of the child born unto her partner.’ […]

Why does Comprehensive Chromosome Screening (CCS) by array-CGH reduce miscarriage rates?

Miscarriage rates in the general population with no fertility problems range around 15-20%. In other words, one out of every five couples who achieve pregnancy suffers a spontaneous miscarriage, and 5% of these couples suffer it more than once. Even when pregnancy is achieved with the help of assisted reproduction techniques, miscarriage rates do not vary. For this reason, it is important when couples come to our clinic seeking reproductive counselling to perform comprehensive testing and design an adequate protocol for their case to secure the best result, which is a healthy baby at home, minimising the chances of miscarriage. In order to do that, one should know that miscarriages and pregnancy losses are caused by different reasons (uterine problems, immunological problems, and so on), and yet in half the cases there are chromosomal abnormalities in the embryo that prevent pregnancies to progress, hence causing miscarriages. Normal embryos have two copies of each chromosome, one inherited from the father and the other from the mother, and the chromosomal anomalies they may suffer involve a change in the number of copies, producing an imbalance in their genetic load which might block embryo development. […]

Choosing a fertilisation technique when oocyte counts are poor. IVF or ICSI?

A low ovarian response is an increasingly common situation for clinicians. It is mainly associated with delayed motherhood and, accordingly, with lower ovarian reserves. In this type of patients, the number of oocytes retrieved after puncture is normally limited. In this situation, choosing the most adequate fertilisation technique, conventional IVF or Intracytoplasmic Sperm Injection (ICSI), may stir a little controversy (of course, provided that the sperm quality and the medical history lead us to consider conventional IVF as a reasonable option). […]