Patients with a previous history of ectopic pregnancy are nine times more likely to have ectopic pregnancy, according to a new study published in the International Journal of Gynecology & Obstetrics¹. Likewise, a history of pelvic inflammatory disease (PID) increases the likelihood of ectopic pregnancy by fourfold.

The systematic review and meta-analysis aimed to determine risk factors associated with the occurrence of ectopic pregnancy. Observational studies published from 2000 onward in English and Portuguese were included in the analysis after a search of electronic databases, including MEDLINE/PubMed, LILACS, The Cochrane Library, and the Virtual Health Library (VHL). Studies with undefined methodologies or published before 2000 were excluded. A total of 16 risk factors were evaluated. Eleven studies conducted between 2003 and 2019, with a total of 25,051 patients were analyzed.

The study identified several strong risk factors for ectopic pregnancy, including a history of ectopic pregnancy (odds ratio [OR] 9.03), PID (OR 4.00), infertility (OR 3.70), abdominal and pelvic surgeries (OR 5.60), and previous tubal ligation (OR 5.59).

Additionally, advanced maternal age, smoking, multiple sexual partners, history of spontaneous and induced abortion, emergency contraception use, and intrauterine devices were found to slightly increase the risk of ectopic pregnancy. Advanced maternal age, specifically between 30 to 34 years (OR 1.13) and =40 years (OR 1.46), as well as marital status (OR 1.19) were associated with a slight increase in the risk of ectopic pregnancy. Oral contraceptive use was linked to a reduced risk (OR 0.77), while condom use had a negligible impact (OR 0.93).

The findings emphasize the need for screening policies for women at high-risk to improve early detection and outcomes. Women with a history of ectopic pregnancy, PID, infertility, prior tubal surgery, or tubal ligation should be particularly closely monitored due to their significantly increased risk. Targeted patient counseling, and preventive measures to reduce the associated morbidity and mortality can improve maternal outcomes.

Brim ACS, Barretto VRD, Reis-Oliveira JG, da Silveira de Araújo RB, Romeo ACDCB. Risk factors for ectopic pregnancy occurrence: systematic review and meta-analysis. Int J Gynaecol Obstet. 2025;168(3):919-32.