Recurrent Pregnancy Loss
Recurrent Pregnancy Loss is a very emotionally distressing experience for women and couples. Approximately one in four pregnancies miscarry it is unfortunately not uncommon, particularly in the first trimester. About 1% of women will have recurrent miscarriages, but many of these will end up with a baby. Causes of Recurrent Pregnancy Loss:
This is the commonest cause for miscarriage and is due to the embryo not having the correct number of chromosomes (aneuploidy).
This becomes much more likely as a woman gets older, due to the age effect on the eggs. There is a 70% risk of miscarriage at the age of 46 years, whereas it is 15-20% under the age of 30 years.
Fibroids or polyps that come into the cavity of the uterus can increase the rate of miscarriage. Some women are born with an abnormality in their uterus that can also lead to an increased rate of miscarriage
Smoking increases the risk of miscarriage as does being overweight.
Poorly controlled medical conditions, such as thyroid disease or diabetes, can increase the risk for miscarriage. Abnormalities of the immune system or blood-clotting system (thrombophilia) can also cause miscarriages too.
About 60% of recurrent miscarriage cases are unexplained, i.e. there is no identified cause.
Treatment of Recurrent Pregnancy Loss
There are nowadays many different approaches that your doctor can discuss with you towards trying to reduce the occurrence of another miscarriage.
Pre-implantation Genetic Testing
What is PGT?
Preimplantation genetic testing or PGT was formerly called PGS (preimplantation genetic screening) and PGD (preimplantation genetic diagnosis). The terms were changed following a meeting at the World Health Organization by a large multinational group of experts. The reason for the change was to standardise the terms across groups of people working in fertility care globally and to make them more accurate. PGS was changed to PGT-a, where “a” stands for aneuploidy, or an abnormal number of genes. PGD is now called PGT-m, for monogenomic (or single gene) disease. There is one additional term, PGT-sr, which stands for “structural rearrangement”. This is used for people who have a genetic condition called a “translocation”.
How is it done?
PGT is performed by removing a small number of “trophectoderm” cells from the embryo, generally at day 5-6 of development. These cells are destined to become the placenta and do not become part of the embryo. These cells are removed using a specifically designed laser. A computer allows the embryologist to precisely control the laser energy output, making this method more precise. Laser takes less time and does not expose the embryos to potentially adverse chemicals, so embryos spend less time out of the optimal culture conditions of the incubator. These sampled cells are then frozen and sent to a genetics lab for analysis, which may take 2-4 weeks
What are the risks?
The removal of the embryo cells does not seem to increase the risk of damage to the embryos however there very few studies reporting this data. Sampling the trophectoderm as we currently do seems to be less damaging than older techniques such as “blastomere biopsy”. Long term risks to the health of the baby from PGT are not know yet either, however the added knowledge of the genetics of the embryo has been shown to decrease the odds of miscarriage and improve the chance of implantation, there by resulting in more live births.
Costs are a major concern as IVF can be very expensive and PGT is an additional expense, and it is not a perfect test. The testing can have an error rate up to 2%, meaning some embryos may be deemed abnormal when they have the right number of chromosomes. Additionally, not all genetically competent embryos implant. For some, the testing can be a very helpful tool but for others it may be an added expense without a robust benefit.
Sometimes you may wish to be investigated to see if there is a problem that is stopping you from getting pregnant or you may just be curious to find out about your fertility.
A few tests that you may wish to carry out are:
Ovarian Reserve testing
Treatments for infertility
After your doctor has taken your history and seen the results of some baseline tests, the following treatments may be discussed:
Lifestyle modification and increase frequency of intercourse
Ovulation induction (with or without Metformin for PCOS)
Laparoscopic or Hysteroscopic treatment
IUI (Intra Uterine Insemination)
IVF (In Vitro Fertilisation)
ICSI (Intra Cytoplasmic Sperm Injection)