Recurrent miscarriage is defined as 2 or more consecutive miscarriages. Any unwanted, spontaneous pregnancy loss prior to the 20th week of pregnancy is considered a miscarriage. Miscarriages are a relatively common occurrence, affecting nearly 15% of all pregnancies. However, repeated miscarriages suggest that there may be an underlying medical condition. Women experiencing repeat miscarriages should consult with a specialist to avoid further losses.
There are two types of pregnancies:
- Chemical pregnancy: Pregnancies that are confirmed only by a blood test ((β-hCG) are considered chemical pregnancy because gestation is only confirmed through chemical means not through an ultrasound.
- Clinical pregnancy: Clinical pregnancy reaches a stage where the gestational sac can be seen with a transvaginal ultrasound examination.
In life outside of fertility treatment settings, most women do not know they had chemical pregnancies, since most women do not have pregnancy test so early in their pregnancy. During infertility treatments, however, we do diagnose these very early pregnancy losses, because every IVF treatment cycle is followed up with a very early pregnancy test, β-hCG blood test.
Possible cause(s) for recurrent miscarriage
Some health conditions are known to lead to miscarriage. Others have been linked to it, but it’s not fully understood how or why they may play a part in a miscarriage.
Some conditions that are known to lead to possible recurrent miscarriage
- Genetic problems. You or your partner may have an abnormality on one of your chromosomes, which doesn’t cause a problem until it is passed on to your baby.
- A problem that makes your blood clot when it shouldn’t. This is called antiphospholipid syndrome (APS), also known as sticky blood syndrome.
- An inherited blood-clotting disorder, called thrombophilia. It’s similar to APS, but is something you are born with rather than acquire.
- Possible problems with your uterus or cervix. You may have an uterus that has an abnormal shape
- A vaginal infection, increases the risk of late miscarriage and premature birth
- Hormone problems. Some conditions, such as polycystic ovaries have been linked to repeat miscarriage
- Age factor. The older you are, the more likely you are to experience a miscarriage
- Lifestyle factors such as cigarettes, alcohol, drugs and environmental toxins
Signs of a Miscarriage
In early pregnancy, spotting is normal, however if you experience menstrual-like cramps or severe abdominal pain and bleeding, you may be experiencing a miscarriage and should contact your doctor. The doctor may exam to check the cervix; if it’s dilated a miscarriage is likely. If you had an early miscarriage, chances are you won’t need any medical treatment. However, in some cases a procedure called a dilation&curettage (D&C) may needed to remove the embryonic tissues.
Testing to prevent miscarriage
- Hormonal Tests. Hormones such as prolactin, thyroid and progesterones levels are tested for any abnormalities.
- Structural Tests. A hysterosalpingogram is done to evaluate the shape and size of your uterus and to rule out possible scarring in the uterus, polyps, fibroids or a septal wall, which could affect implantation. More evaluations are done if there is a concern with the uterine cavity with a hysteroscopy with combination of laparoscopy.
- Uterine Lining Tests. An endometrial biopsy is done on menstrual cycle day 21 or later to determine whether or not the endometrium- lining is thick enough for the fertilized egg to implant. If the lining is not sufficient, a hormone treatment will start.
- Chromosomal Tests. If chromosome testing is needed, the couple will have blood tests to make sure there is no translocation of genes (a condition in which the number of genes is the normal 46, but they are joined together abnormally). This condition can result in pregnancy loss.
- Immunologic Tests: Blood tests are done to check for immunologic responses that may cause pregnancy loss include antithyroid antibodies, the lupus anticoagulant factor and anticardiolipin antibodies. Lupus and anticardiolipin antibodies appear to influence blood clotting mechanisms within the placenta as it develops. There are also blood tests that check for protective blocking factors. These are essential to protect the pregnancy from being rejected by the mother’s body.