Recurrent miscarriage, defined as the loss of three or more consecutive pregnancies, occurs in approximately 1% of couples attempting to bear children.
• Should women with recurrent miscarriage be investigated for the antiphospholipid syndrome or thrombophilias?
Five to 15% of women with recurrent miscarriage have clinically important antiphospholipid antibody titers, as compared with 2% to 5% of unselected obstetrical patients. Because results may be transiently positive after infection, the antiphospholipid syndrome should be diagnosed only when two tests performed 12 or more weeks apart are positive. It also has become common to screen patients with recurrent miscarriage for thrombophilias, although it is uncertain whether this screening is warranted.
• What imaging is recommended in evaluating a woman with recurrent miscarriage?
Uterine malformations, most commonly arcuate and septate uteruses, are detected in 10 to 25% of women with recurrent miscarriage as compared with 5% of women with sporadic miscarriage, and evaluation of the uterine cavity (primarily to look for a septum) is recommended by professional organizations in women with recurrent miscarriage. Sonohysterography and hysterosalpingography are noninvasive screening tests used to evaluate uterine cavity and shape; MRI, hysteroscopy, or both may be more informative but are more expensive and invasive, respectively.
Morning Report Questions
Q: What is the role of parental karyotype testing for couples with recurrent miscarriage?
A: In 3 to 6% of cases of recurrent miscarriage one partner (more often the woman) has a balanced chromosomal rearrangement. The most common abnormality is a translocation, either reciprocal or robertsonian. Parental karyotyping is expensive and is not always covered by third-party payers. Because available treatment (in vitro fertilization with preimplantation genetic diagnosis) has not been shown to improve the outcome, as compared with that of spontaneous conception, some couples may choose to forego parental karyotype testing.
Q: What is the role of performing a karyotype analysis of the conceptus?
A: Though controversial, some experts recommend karytoype analysis of the conceptus in couples with recurrent miscarriage to avoid unnecessary evaluation and treatment and because an aneuploid conceptus indicates a somewhat greater likelihood of success with a subsequent pregnancy.
Table 1. Evaluation of a Woman with Recurrent Miscarriage.