The UK's Royal College of Obstetricians and Gynaecologists (RCOG) has issued new evidence-based guidance for managing couples with recurrent miscarriage — defined as the loss of three or more pregnancies. Approximately 1 percent of all women will experience recurrent miscarriage. This incidence is greater than chance alone, since the theoretical risk of three consecutive pregnancy losses is 0.34 percent (based on 10-15 percent of all clinically recognized pregnancies ending in miscarriage). Maternal age and previous miscarriage are two known independent risk factors for a further miscarriage.

The new report, The Investigation and Treatment of Couples with Recurrent Miscarriage, contains a series of clinical recommendations, each assigned a grade according to the level of evidence in support of it. In the absence of evidence either way, certain recommendations are considered best practice based on the clinical experience of the college's guideline development group.

What works and what doesn't?

The report makes 18 main recommendations, covering genetic, anatomical, endocrine and immune factors, cervical weakness, infective agents, inherited thrombophilic defects, and unexplained recurrent miscarriage. The advice, supported by detailed discussion and explanation in the full report, includes:

* "All women with recurrent miscarriage should have a pelvic ultrasound to assess uterine anatomy and morphology."

* "Routine screening for occult diabetes and thyroid disease with oral glucose tolerance and thyroid function tests in asymptomatic women presenting with recurrent miscarriage is uninformative."

* "There is insufficient evidence to evaluate the effect of progesterone supplementation in pregnancy to prevent a miscarriage."

* "Routine screening for thyroid antibodies in women with recurrent miscarriage is not recommended."

* "In women with a history of recurrent miscarriage and aPL [antiphospholipid antibodies], future live birth rate is significantly improved when a combination therapy of aspirin plus heparin is prescribed." However: "Pregnancies associated with aPL treated with aspirin and heparin remain at high risk of complications during all three trimesters."

* "Screening for and treatment of bacterial vaginosis in early pregnancy among high risk women with a previous history of second-trimester miscarriage or spontaneous preterm labor may reduce the risk of recurrent late loss and preterm birth."

The guidance can be seen in full at the RCOG's website.

Source: RCOG report: The Investigation and Treatment of Couples with Recurrent Miscarriage, Issue 11: 2 Jun 2003