ABSTRACT
Most pregnancy losses are spontaneously aborted when the conceptus is undergoing embryonic development. Pregnancy loss is a significant health concern in economically advanced societies, where traditional early reproduction is replaced by a social trend towards establishing the mother’s career before starting reproduction. As the whole reproductive period may be shortened to 5-7 years, each pregnancy becomes precious. Finding the cause of pregnancy loss is essential for prognosis, recurrence risk counselling, and management of future pregnancies. Approximately 1% of fertile couples will experience recurrent early pregnancy losses.1 Although recurrent early pregnancy losses have been associated with maternal factors such as maternal thrombophilic disorders, structural uterine anomalies, maternal immune dysfunction, endocrine abnormalities, and parental chromosomal anomalies (as described in other chapters of this book), approximately 50% of recurrent miscarriages are classified as idiopathic following maternal investigation. For affected couples, idiopathic pregnancy loss creates a great deal of grief and anxiety about the outcome of future pregnancies. It is currently unclear whether embryonic maldevelopment is a contributiory factor in these cases. Investigations of the dead embryo are rare.2,3 Demised embryos cannot be investigated for several practical reasons. Most losses occur when the conceptus is undergoing embryonic development. The small size of the embryo precludes detailed examination, either by ultrasound (due to limitations of resolution) or by pathological techniques. Both instrumental evacuation and spontaneous passage damage the embryo. It is rarely retrieved whole due to its minute size and fragility.4
