In vitro fertilization outcome relative to embryo transfer difficulty: a novel approach to the forbidding cervix.

ABSTRACT

OBJECTIVE: To assess the impact of ET difficulty on IVF outcome and to optimize the ET procedure. DESIGN: Retrospective analysis of IVF outcome by ET catheter type and ET difficulty. Prospective treatment and follow-up of patients with a history of extremely difficult cervical passage. SETTING: Large university-based IVF program. PATIENT(S) All patients < 40 years of age undergoing IVF-ET from September 1995 to May 1998. INTERVENTION(S) Surgical correction of cervical stenosis. MAIN OUTCOME MEASURE(S) Pregnancy and embryo implantation rates. RESULT(S) Only 0.6% of ETs were "extremely difficult." Pregnancy rates were not statistically significantly different among ETs graded easy, moderate, and difficult. In contrast, no pregnancies occurred in the rare "extremely difficult" ET group. Eight patients with a history of extremely difficult cervical passage underwent surgical correction of their cervical stenosis. Twelve postoperative IVF-ET in these women resulted in eight clinical pregnancies, six of which were multiple gestations. The embryo implantation rate of these cycles was 42.2%. CONCLUSION(S) Patients with a history of extremely difficult ET may benefit from hysteroscopic evaluation and possible modification of their cervical canal before a future IVF attempt.