ABSTRACT
Miscarriage is the commonest complication of pregnancy. It is estimated that between 10% and 15% of clinically recognized pregnancies miscarry. In contrast, recurrent miscarriage, the loss of three or more consecutive pregnancies, is relatively uncommon, affecting between 1% and 2% of couples trying to conceive.1 Whilst the most common cause for any single miscarriage is a sporadic fetal chromosome abnormality, the incidence of which increases with advancing maternal age, women who repeatedly miscarry tend to lose euploid as apposed to aneuploid fetuses.2,3 This suggests that some women with recurrent miscarriage have a persistent underlying cause to account for their pregnancy losses. These causes, which can be simply divided into those that are embryological in origin, such as aneuploidies, and those that are related to the maternal environment, are shown in Table 1.
