Miscarriages in the first trimester are very common, and according to The Society of Obstetricians and Gynaecologists of Canada (SOGC), a miscarriage will occur in 16-20% of pregnancies. More than 30% of all fertilized eggs miscarry, often even before the pregnancy is recognized. While a miscarriage is a normal way for our body to expel an unviable embryo, the impact of the loss is one of the most traumatic and devastating experiences for a woman to go through. The grief and emotional impact are often underestimated, misunderstood and unvoiced. The emotional healing usually takes much longer than the physical recovery, and it is important to find support and deal with both emotional and physical aspects of the loss before trying to conceive again. Fortunately, for most women, one miscarriage won’t affect their chances for a successful pregnancy in the future. However, 1-2% of women will suffer multiple miscarriages, which is also clinically referred as Recurrent Pregnancy Loss (RPL). The challenge is to differentiate successfully sporadic miscarriages from RPL, or in other words, when do miscarriages become a concern? And when is it time to see a specialist? The revised definition of Recurrent Pregnancy Loss (RPL) is two consecutive pregnancy losses before 20 gestational weeks. Therefore, if you had two consecutive or three nonconsecutive miscarriages, you should consult with a fertility specialist.
Patients with RPL are usually able to conceive naturally, and therefore RPL is not clinically defined as infertile. However, early in their pregnancy, something causes them to miscarry.
The main causes for RPL can be divided into seven main groups. Identifying what causes RPL will help the specialist decide on the course of treatment.
Genetic Abnormalities– Most of the miscarriages are the result of genetic embryonic anomalies and are random events. Advanced Maternal age is associated with an exponentially increased risk for miscarriages due to genetic abnormalities. The fertility specialist will send both couples for chromosomal testing (karyotyping) to evaluate them for any genetic abnormalities. This is done by a simple blood test. If genetic abnormalities are the cause of RPL, the fertility specialist will suggest IVF and preimplantation genetic testing for aneuploidy (PGT – A) to ensure that the embryos are chromosomally normal before the embryo transfer. Transferring a chromosomally normal embryo improves the chances for a live birth significantly.
Anatomic Abnormalities – Congenital uterine abnormalities such as Uterine Septum, and other acquired uterine abnormalities such as scarring or fibroids could cause miscarriages. The fertility specialist will evaluate the uterine by a variety of imaging tests such as sonohysterogram (Sono-HSG), hysteroscopy, MRI and more. If the doctor confirms that anatomic abnormalities are causing the pregnancy loss, surgery could be offered to correct the anatomic defect and prevent future miscarriages.
Hormonal Disorder– There is a correlation between endocrine disorders such as uncontrolled diabetes or thyroid disorders and pregnancy loss. The specialist will order blood tests to evaluate if blood sugar levels or TSH levels are causing the miscarriages. In case of abnormal levels, medication will be prescribed to normalize these conditions.
Autoimmune Diseases – The Antiphospholipid Antibody (APA) Syndrome is an autoimmune disorder that may be associated with RPL. It involves several types of antibodies such as the Lupus anticoagulant (LAC) and the anti-cardiolipin antibody (ACA). The rate of LAC is 7% and of ACA is 15%, among pregnant women, and elevated LAC or ACA in the serum are believed to cause thrombosis in the maternal blood circulation, which can lead to a miscarriage. Presently, the medical treatment of the APA syndrome includes blood thinners like low molecular weight heparin with low-dose aspirins.
Clotting Disorder– Inherited thrombophilias is abnormal blood coagulation genetic disease that leads to blood clots in blood vessels. Women with thrombophilias have higher risks to miscarry. The specialist will assess your risks by your family medical history. The specialist may also suggest further screening tests to evaluate the risk. Patients with higher risks will often be treated with blood thinners.
Lifestyle – Smoking, alcohol, obesity, and drug use are associated with RPL. Keeping a healthy diet and lifestyle is good for your overall health and may also increase your chances of a successful pregnancy.
Unexplained – In about 50% of RPL the cause cannot be identified and remains unexplained. Patients with unexplained RPL can still benefit from preimplantation genetic testing (PGT – A) as selecting an embryo with healthy karyotype (chromosome makeup) can increase the chances for a successful pregnancy.
Comprehensive diagnostic testings allow us to tailor a course of treatment that is right for you. We strongly believe that personalized and personal reproductive care can make a big difference in success rates. If you have any questions about pregnancy loss, don’t hesitate to reach out, our team of professionals is here to listen and help!