Recurrent miscarriage: causes, evaluation, and treatment

Recurrent miscarriage or fetal loss syndrome (also known as fetal wastage syndrome) is characterized by recurrent spontaneous abortion. There are many syndromes associated with recurrent fetal loss, including anatomic anomalies, endocrine/hormonal abnormalities, genetic/chromosomal abnormalities, and blood coagulation protein/platelet defects. Many of these syndromes are treatable, leading to normal term pregnancy, if the clinician is astute and vigorously pursues a thorough evaluation of why the patient has suffered unexplained, spontaneous miscarriages. There is no uniform agreement on how many spontaneous, unexplained miscarriages are needed to diagnose recurrent fetal loss; we generally pursue an evaluation for causation if a women has had 2 or more such events. In this article, we discuss the common reasons for recurrent fetal loss, plus diagnostic procedures to consider in pinpointing the problem, such as cytogenetic studies, blood coagulation protein/platelet tests, hysterosalpingography, sonography, and magnetic resonance imaging. We also describe management strategies that often lead to successful pregnancy outcome when the underlying problem is addressed. For example, in the case of thrombotic defects, a common cause of recurrent fetal loss, we report a 100% success rate in achieving a normal-term delivery among women who took low-dose (81 mg/day) aspirin preconception followed by postconception low-dose (5000 units q 12 h) heparin.