Ectopic pregnancy occurs when the blastocyst (embryo) implants at locations other than the endometrium, or lining of the uterine cavity. The most common site of occurrence is in the fallopian tube. Other sites include the cervix, the cornual portion of the uterus, the ovary, and the abdominal cavity. The incidence of ectopic pregnancy has been steadily increasing. In the united States, about 2 out of every 100 pregnancies end in an ectopic pregnancy. The increased incidence of ectopic pregnancy is thought to be due to the increased incidence of salpingitis (infection of the fallopian tubes), due to chlamydia or other sexually transmitted diseases. The delay in childbearing to the 30s, the use of progestin-only contraception, and tubal surgery including tubal sterilization also contribute to the increased incidence seen. Other causes include a congenital or acquired abnormality of the fallopian tube, hormonal imbalances, ovulation induction medications, and abnormality of embryonic development. In some social groups, the incidence of ectopic pregnancy is higher. In African American women and unmarried women, the risk of death from a ruptured ectopic pregnancy is higher than in the general population. Although the rates of ectopic pregnancies have increased, the percentage of ectopic pregnancies that become fatal has decreased.
The most common presenting symptoms of an ectopic pregnancy are abdominal pain, absence of menses, and irregular vaginal bleeding. The diagnosis of ectopic pregnancies is made with a thorough history and physical examination, and a variety of specialized tests including obtaining serial serum HCG levels (serial levels of substance in the blood produced by the developing fetus), performance of a transvaginal ultrasound (sound wave visualization of the structures around the vagina), culdocentesis looking for internal bleeding (examination of fluid to determine presence of blood), and laparoscopy (specialized examination using a small tube). Ninety percent of women with ectopic pregnancies have an abnormal pattern of serially obtained quantitative HCG levels.
Management of ectopic pregnancies includes surgical and nonsurgical management. Current surgical treatment includes laparoscopy or laparotomy. Nonsurgical management includes medical therapy with methotrexate or expectant management where the patient is closely observed. The rate of repeat ectopic pregnancies after a single ectopic pregnancy is about 15%. The subsequent conception rate in women with an ectopic pregnancy is about 60%.