In-vitro fertilization treatment for unexplained recurrent abortion: a pilot study.

To determine the effectiveness of in-vitro fertilization (IVF) and embryo transfer for patients with unexplained habitual abortion, we carried out a prospective observational study using a historical comparison group. A total of 12 couples with three or more (mean 4. 91, range 3-10 miscarriages) first trimester spontaneous abortions of unknown aetiology were treated with IVF and embryo transfer (group 1). Patients underwent IVF after combined gonadotrophin-releasing hormone agonist/gonadotrophin treatment for ovarian stimulation, and three to four embryos were replaced into the uterus in all women. Eight of the 12 women (66.6%) in group 1 became pregnant (one patient after a frozen-thawed embryo transfer), and all of them had viable pregnancies. A patient with 10 previous abortions became pregnant and carried to term after IVF and embryo transfer, and subsequently miscarried two new spontaneous gestations. A historical comparison group (group 2) included the last eight women with unexplained recurrent abortion (mean 4, range 3-8 miscarriages) who underwent the same investigations for the condition and received identical early supportive care in their next spontaneous pregnancy as patients in group 1. Three of the eight pregnancies in group 2 ended in an abortion. Our results suggest that IVF and embryo transfer may be a new therapeutic approach for unexplained recurrent miscarriage.