ABSTRACT

Introduction: Spontaneous heterotopic pregnancy is extremely rare. It is diagnosed where at least two pregnancies are present simultaneously at different implantation sites, and where one of them is an intrauterine pregnancy. We present a case of heterotopic pregnancy which presented to the early pregnancy assessment clinic with abdominal discomfort at five weeks gestational age.

Case Report: A 32-year-old woman presented to the early pregnancy assessment clinic with lower abdominal pain. She was seen in the fertility clinic as she was trying to conceive for more than two years. She was para 2 having had 2 normal vaginal deliveries. She successfully achieved pregnancy on Clomid tablets 50 mg daily from day 2 to day 5 of the cycle. An ultrasound scan in the early pregnancy assessment clinic showed pregnancy of unknown location (PUL) with endometrial thickness of 10 mm at five weeks gestational age. She was subsequently diagnosed with heterotopic pregnancy with extrauterine mass measuring 1.64 cm in size. This was associated with an intrauterine sac with an embryo of about six weeks gestational age. She had laparoscopic right salpingectomy at gestational age of six weeks. She continued with her intrauterine pregnancy until term, and she had spontaneous normal vaginal delivery at 39⁺⁴ weeks.

Conclusion: Heterotopic pregnancy is a rare condition, estimated to occur in about 1/30,000 pregnancies. The most common extrauterine location of ectopic pregnancy is the fallopian tube although it can occur in other sites such as cervix, ovary, or anywhere intra-abdominally. Heterotopic pregnancy tends to be overlooked after confirming an intrauterine pregnancy; however, assessment of both adnexae is very important to exclude heterotopic pregnancy. Early detection and treatment of heterotopic pregnancy is key to prevent rupture of the ectopic pregnancy. This has significant consequences in maternal morbidity and mortality and, furthermore, increases the chance of intrauterine pregnancy continuing to term.