What are the main causes of infertility?
Infertility is defined as the inability to carry a pregnancy to term. It may be primary infertility when you have never achieved pregnancy or secondary when you already have a child or children at home. It is also referred to as recurrent or repeated miscarriage. This implies 2 consecutive miscarriages or 3 interspersed around one birth.
The most common causes of repeated miscarriage are:
- Genetic: The presence of balanced chromosomal abnormalities in the parents (translocations, inversions) can produce conception imbalance which is incompatible with the creation of life and so produces a miscarriage. In these cases it is advisable to perform a karyotype on the parents as well as on the miscarriage itself. A mother of advanced age is also associated with an increased risk of miscarriage due to genetic causes.
- Anatomical: Uterine abnormalities may be associated with repeated miscarriage. It can be diagnosed by a transvaginal ultrasound (2D or 3D), an HSG, an MRI or especially a hysteroscopy. The septate uterus is the main alteration associated with congenital uterine infertility. Its etiology is a defect in the re-absorption of the fused caudocranial Müllerian ducts. The treatment of such is hysteroscopic septoplasty. Submucosal fibroids is an issues but this can be treated by a hysteroscopic myomectomy.
- Immunologic: The presence of several autoantibodies (defences that act against the body itself) can cause miscarriage. The most frequently associated are antiphospholipid and anticardiolipin antibodies.
- Thrombophilia genetic abnormalities of the patient’s coagulation system which creates a hypercoagulable state, which may be associated with repeated miscarriage. These include the Factor V Leiden, prothrombin 20210, hyperhomocysteinemia, etc.
- Endocrine: Poorly controlled insulin-dependent diabetes, mainly hypothyroidism, may be associated with repeated miscarriage.