Heterotopic pregnancy

A heterotopic pregnancy is a complication of pregnancy in which both extrauterine (ectopic) pregnancy and intrauterine pregnancy occur simultaneously. It may also be referred to as a combined ectopic pregnancy, multiple‐sited pregnancy, or coincident pregnancy. The most common site of the extrauterine pregnancy is the fallopian tube. However, other sites of implantation include the cervix, ovary, and abdomen. Although heterotopic pregnancies were once thought to be a rare phenomenon, the incidence has increased due to the increasing use of assisted reproductive technologies. In a heterotopic pregnancy there is one fertilized ovum which implants normally in the uterus, and one fertilized ovum which implants abnormally, outside of the uterus. In the general population, the major risk factors for heterotopic pregnancy are the same as those for ectopic pregnancy: Previous history of ectopic pregnancy Tubal surgery Pelvic inflammatory disease Use of an intrauterine device In utero diethylstilbestrol exposure Smoking Women participating in an assisted reproductive program have an increased risk of heterotopic pregnancy for several reasons including: Higher incidence of ovulation due to treatment Multiple embryo transfers Technical factors in embryo transfer which may increase the risk for ectopic and heterotopic pregnancy Higher incidence of tubal malformation and/or tubal damage in this group Higher levels of estradiol and progesterone due to hormonal treatment Heterotopic pregnancies present with unspecific clinical symptoms. This means the symptoms of a heterotopic pregnancy can be the same symptoms found in several other medical conditions. The most common clinical symptoms are abdominal pain, vaginal bleeding, enlarged uterus, and/or an adnexal mass. The vague symptoms found in heterotopic pregnancies can contribute to the delayed diagnosis of this condition, which can lead to devastating consequences, including a ruptured ectopic pregnancy.