This blog is an update. It reflects new recommendations from the American Society of Reproductive Medicine.
Recurrent pregnancy loss (RPL) has been defined as the loss of 2-3 or more consecutive pregnancies in the first or early second trimester of pregnancy. Other terms for RPL include recurrent spontaneous abortion, miscarriage, or habitual abortion. It is estimated that fewer than 5% of women will experience 2 consecutive losses and less than 1% will experience 3 or more. The majority of pregnancy loss occurs before 10 weeks of pregnancy. The rate of miscarriage increases with maternal age, especially after age 35. In women over 40, miscarriage rates approach 50%
Recurrent pregnancy loss is a distressing problem as frequently the cause(s) are unknown. Even when a detailed evaluation is completed, a definite cause is established in no more than 50% of couples. There are also many unproven hypotheses and poorly designed clinical studies, resulting in various treatments for RPL, many of which are without proven benefit.
Immunologic causes of RPL (often referred to as Alloimmune) continue to remain controversial and largely unproven. It has been theorized that there may be a group of women in whom their immune system recognizes pregnancy and rejects it. Immunotherapy has been proposed to reduce the risk of rejection of pregnancy and improve the opportunity for a successful pregnancy. The results of published medical studies are conflicting. The best available studies do not indicate that Immunotherapy is any more successful than no treatment. One must consider the costs and possible side effects of current utilized therapies in light of the lack of scientific evidence of effectiveness.
A very well-done and updated Committee Opinion from the American Society of Reproductive Medicine entitled “Evaluation and treatment of recurrent pregnancy Loss: a committee opinion” was just released in the November edition of Fertility and Sterility. (Fertil Steril 2012; 98:1103-11). The committee recommends that the evaluation for PRL can proceed after 2 consecutive clinical pregnancy losses. Psychological counseling and support should be offered to each couple.
The evaluation of RPL includes:
• Assessment of lifestyle variables
• Chromosome Analysis of the couple
• Chromosomal analysis of products of conception
• Sonohysterogram, Hysterosalpingiogram (HSG) and/or Hysteroscopy to screen for uterine abnormalities
• Screening for Thyroid and Prolactin abnormalities
• Screening for Lupus Anticoagulant, Anticardiolipin Antibodies and anti-β1-Glycoprotein I.
• Women with persistent moderate-to-high antiphospholipid antibodies can be treated with low-dose Aspirin and unfractionated Heparin.
The treatment of RPL should be based on the above evaluation as well as the couple’s unique history. Treatment of recognized factors such as uterine abnormalities and hormonal imbalances will increase the chance of a successful pregnancy. If all testing is normal, the chances of a favorable outcome are good. In studies of women with unexplained pregnancy loss where no active medical intervention is used, successful pregnancies occur in 50- 65% of cases.