Am Fam Physician. 2020;101(10):599-606
Author disclosure: No relevant financial affiliations.
Ectopic pregnancy occurs when a fertilized ovum implants outside of the uterine cavity. In the United States, the estimated prevalence of ectopic pregnancy is 1% to 2%, and ruptured ectopic pregnancy accounts for 2.7% of pregnancy-related deaths. Risk factors include a history of pelvic inflammatory disease, cigarette smoking, fallopian tube surgery, previous ectopic pregnancy, and infertility. Ectopic pregnancy should be considered in any patient presenting early in pregnancy with vaginal bleeding or lower abdominal pain in whom intrauterine pregnancy has not yet been established. The definitive diagnosis of ectopic pregnancy can be made with ultrasound visualization of a yolk sac and/or embryo in the adnexa. However, most ectopic pregnancies do not reach this stage. More often, patient symptoms combined with serial ultrasonography and trends in beta human chorionic gonadotropin levels are used to make the diagnosis. Pregnancy of unknown location refers to a transient state in which a pregnancy test is positive but ultrasonography shows neither intrauterine nor ectopic pregnancy. Serial beta human chorionic gonadotropin levels, serial ultrasonography, and, at times, uterine aspiration can be used to arrive at a definitive diagnosis. Treatment of diagnosed ectopic pregnancy includes medical management with intramuscular methotrexate, surgical management via salpingostomy or salpingectomy, and, in rare cases, expectant management. A patient with diagnosed ectopic pregnancy should be immediately transferred for surgery if she has peritoneal signs or hemodynamic instability, if the initial beta human chorionic gonadotropin level is high, if fetal cardiac activity is detected outside of the uterus on ultrasonography, or if there is a contraindication to medical management.
Ectopic pregnancy occurs when a fertilized ovum implants outside of the uterine cavity. The prevalence of ectopic pregnancy in the United States is estimated to be 1% to 2%, but this may be an underestimate because this condition is often treated in the office setting where it is not tracked. 1 , 2 The mortality rate for ruptured ectopic pregnancy has steadily declined over the past three decades, and from 2011 to 2013 accounted for 2.7% of pregnancy-related deaths. 1 , 3 Risk factors for ectopic pregnancy are listed in Table 1 4 , 5 ; however, one-half of women with diagnosed ectopic pregnancy have no identified risk factors. 4 – 6 The overall rate of pregnancy (including ectopic) is less than 1% when a patient has an intrauterine device (IUD). However, in the rare case that a woman does become pregnant while she has an IUD, the prevalence of ectopic pregnancy is as high as 53%. 7 , 8 There is no difference in ectopic pregnancy rates between copper or progestin-releasing IUDs. 9
| Clinical recommendation | Evidence rating | Comments |
|---|---|---|
| A discriminatory β-hCG level as high as 3,500 mIU per mL (3,500 IU per L) should be used when a woman wishes to avoid unnecessary intervention in a potentially viable intrauterine pregnancy. 18 , 19 | C | Expert opinion and consensus guideline in the absence of clinical trials |
| Uterine aspiration should be considered to evaluate for intrauterine chorionic villi in patients with a pregnancy of unknown location. Visualization of chorionic villi differentiates intrauterine pregnancy loss from ectopic pregnancy, avoiding unnecessary administration of methotrexate. 5 | C | Expert opinion and consensus guideline in the absence of clinical trials |
| A single-dose methotrexate protocol is recommended for medical management of patients with ectopic pregnancy and low initial β-hCG levels. 5 | C | Expert opinion and consensus guideline in the absence of clinical trials |
| Urgent surgical referral is indicated when ultrasonography demonstrates an embryo and fetal cardiac activity outside of the uterus. 5 , 25 | C | Expert opinion and consensus guideline in the absence of clinical trials |
| Age > 35 years Cigarette smoking Documented fallopian tube pathology Infertility Pelvic inflammatory disease Pregnancy while intrauterine device is in place Previous ectopic pregnancy* Previous fallopian tube surgery |