Heterotopic Pregnancy with Ipsilateral Adnexal Cyst Causing a Diagnostic Dilemma: A Case Report.

Background: Heterotopic pregnancy is the coexistence of intrauterine and extrauterine (ectopic) pregnancies. This is a relatively rare phenomenon with an incidence of 1 in 30,000 in spontaneously conceived pregnancies and 1 in 100 pregnancies achieved through assisted reproduction. Due to its relative rarity, diagnosis can be challenging.