Heterotopic pregnancy is
**Core Concept**
Heterotopic pregnancy refers to the rare occurrence of a simultaneous intrauterine and ectopic pregnancy, where a woman is pregnant with a fetus inside the uterus and also has an ectopic pregnancy outside the uterus, often in the fallopian tube. This condition is often associated with assisted reproductive technologies (ART) and can lead to significant maternal morbidity and mortality.
**Why the Correct Answer is Right**
The term "heterotopic" is derived from the Greek words "heteros" meaning different and "topos" meaning place. In the context of pregnancy, heterotopic pregnancy occurs when there are two separate gestations in different locations, violating the normal rule of a single intrauterine pregnancy. This phenomenon is often seen in women undergoing in vitro fertilization (IVF), where the fertilized egg may implant in the uterus while another fertilized egg may implant ectopically in the fallopian tube.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because heterotopic pregnancy is not the same as a molar pregnancy, which is a type of gestational trophoblastic disease characterized by an abnormal growth of trophoblastic tissue in the uterus.
* **Option B:** This option is incorrect because heterotopic pregnancy is not a type of ectopic pregnancy that occurs in the cervix, which is a different location and has different clinical implications.
* **Option C:** This option is incorrect because heterotopic pregnancy is not a type of multiple pregnancy, which involves the presence of more than one fetus in the uterus.
**Clinical Pearl / High-Yield Fact**
Heterotopic pregnancy is a rare but potentially life-threatening condition that requires prompt diagnosis and treatment. In cases where a woman presents with symptoms of ectopic pregnancy and a positive pregnancy test, ultrasound and beta hCG levels should be monitored closely to rule out heterotopic pregnancy.
**Correct Answer: D. Definition of heterotopic pregnancy.**