Local medical treatment of interstitial pregnancy after in-vitro fertilization and embryo transfer (IVF-ET): two case reports.

Two cases of interstitial pregnancy (one singleton, one heterotopic twins) were confirmed 31 and 34 days after in-vitro fertilization. Serum human chorionic gonadotrophin concentrations were 35,000 and 86,000 mlU/ml, respectively. They were treated conservatively with transvaginal ultrasonically guided intra-ovular injection of either methotrexate in the singleton pregnancy, or potassium chloride into the ectopic sac of the heterotopic twins. No complications were observed. The intra-uterine pregnancy continued and the patient delivered a 3350 g healthy baby at 39 weeks.