Expectant management of a heterotopic interstitial pregnancy - a case report.

Heterotopic pregnancy is the simultaneous occurrence of two pregnancies at two different implantation sites, mostly intrauterine and extrauterine sites. An interstitial ectopic pregnancy as part of a heterotopic pregnancy is very rare. This report highlights the case of a 40-year-old woman with heterotopic pregnancy who had conceived via assisted reproductive technology. The patient had an interstitial ectopic pregnancy and a viable intrauterine pregnancy. She was treated expectantly and had cesarean delivery of the intrauterine pregnancy at 38 weeks of gestation. Although management options for heterotopic pregnancies include surgical and medical, it may be reasonable to consider expectant management for select cases while weighing risks. In such cases, close monitoring of symptoms and serial ultrasound examinations should be standard.