Risk factors for ectopic pregnancy: a multi-center case-control study

BMC Pregnancy and Childbirth, Aug 2015

Background Ectopic pregnancy (EP) is the leading cause of maternal death during the first trimester of pregnancy. A better understanding of EP risk can help prevent its occurrence. We carried out a multi-center, large-sample, case-control study to evaluate the risk factors for EP in Shanghai, China. Methods Women who were diagnosed with EP (n = 2411) and women with intrauterine pregnancies (n = 2416) were recruited from five hospitals in Shanghai, China. Information regarding the sociodemographic characteristics; reproductive, gynecological and surgical history; and previous and current use of contraceptives was collected from all participants. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated and adjusted for potential confounding factors via multivariate logistic regression analysis. Results The study revealed that the risk of EP was associated with the traditional risk factors including previous EP (Adjusted odds ratio [AOR] = 2.72, 95 % CI: 1.83–4.05), previous Chlamydia trachomatis infection (Adjusted OR = 3.18, 95 % CI: 2.64, 3.84), previous infertility (AOR = 2.18, 95 % CI: 1.66–2.88), previous adnexal surgery (AOR = 2.09, 95 % CI: 1.49–2.93), previous appendectomy (AOR = 1.64, 95 % CI: 1.13–2.37), and previous use of intrauterine devices (IUDs) (AOR = 1.72, 95 % CI: 1.39–2.13). Additionally, EP risk was increased following the failure of most contraceptives used in the current cycle including IUDs (AOR = 16.43, 95 % CI: 10.42–25.89), oral contraceptive pills (AOR = 3.02, 95 % CI: 1.16–7.86), levonorgestrel emergency contraception (AOR = 4.75, 95 % CI: 3.79–5.96), and female sterilization (AOR = 4 .73, 95 % CI: 1.04–21.52). Stratified analysis showed that in vitro fertilization and embryo transfer (IVF-ET) was the main risk factor for EP in women with tubal infertility (AOR = 8.99, 95 % CI: 1.98–40.84), although IVF-ET showed no association with EP in women with non-tubal infertility (AOR = 2.52, 95 % CI: 0.14–44.67). Conclusion In addition to the traditional risk factors, IVF-ET and current IUD use play dominant roles in the occurrence of EP. Attention should be given to women with tubal infertility who have undergone IVE-ET treatment.

A PDF file should load here. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser.

Alternatively, you can download the file locally and open with any standalone PDF reader:

http://www.biomedcentral.com/content/pdf/s12884-015-0613-1.pdf

Risk factors for ectopic pregnancy: a multi-center case-control study

Li et al. BMC Pregnancy and Childbirth Risk factors for ectopic pregnancy: a multi- center case-control study Cheng Li 0 1 3 Wei-Hong Zhao 0 1 Qian Zhu 0 1 Shu-Jun Cao 2 Hua Ping 6 Xiaowei Xi 5 Guo-Juan Qin 4 Ming-Xing Yan 1 Duo Zhang 1 Jun Qiu 1 Jian Zhang 1 3 0 Equal contributors 1 Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University , Shanghai 200030 , China 2 Department of Obstetrics and Gynecology, Songjiang Central Hospital , Shanghai 201600 , China 3 Institute of Embryo-Fetal Original Adult Disease Affiliated to Shanghai Jiao Tong University School of Medicine , Shanghai 200030 , China 4 Department of Obstetrics and Gynecology, Minhang Central Hospital , Shanghai 201100 , China 5 Department of Obstetrics and Gynecology, Shanghai First People's Hospital, Shanghai Jiao Tong University , Shanghai 200080 , China 6 Department of Obstetrics and Gynecology, Songjiang Maternity and Child Health Hospital , Shanghai 201620 , China Background: Ectopic pregnancy (EP) is the leading cause of maternal death during the first trimester of pregnancy. A better understanding of EP risk can help prevent its occurrence. We carried out a multi-center, large-sample, case-control study to evaluate the risk factors for EP in Shanghai, China. Methods: Women who were diagnosed with EP (n = 2411) and women with intrauterine pregnancies (n = 2416) were recruited from five hospitals in Shanghai, China. Information regarding the sociodemographic characteristics; reproductive, gynecological and surgical history; and previous and current use of contraceptives was collected from all participants. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated and adjusted for potential confounding factors via multivariate logistic regression analysis. Results: The study revealed that the risk of EP was associated with the traditional risk factors including previous EP (Adjusted odds ratio [AOR] = 2.72, 95 % CI: 1.83-4.05), previous Chlamydia trachomatis infection (Adjusted OR = 3.18, 95 % CI: 2.64, 3.84), previous infertility (AOR = 2.18, 95 % CI: 1.66-2.88), previous adnexal surgery (AOR = 2.09, 95 % CI: 1.49-2.93), previous appendectomy (AOR = 1.64, 95 % CI: 1.13-2.37), and previous use of intrauterine devices (IUDs) (AOR = 1.72, 95 % CI: 1.39-2.13). Additionally, EP risk was increased following the failure of most contraceptives used in the current cycle including IUDs (AOR = 16.43, 95 % CI: 10.42-25.89), oral contraceptive pills (AOR = 3.02, 95 % CI: 1.16-7.86), levonorgestrel emergency contraception (AOR = 4.75, 95 % CI: 3.79-5.96), and female sterilization (AOR = 4 .73, 95 % CI: 1.04-21.52). Stratified analysis showed that in vitro fertilization and embryo transfer (IVF-ET) was the main risk factor for EP in women with tubal infertility (AOR = 8.99, 95 % CI: 1.98-40.84), although IVF-ET showed no association with EP in women with non-tubal infertility (AOR = 2.52, 95 % CI: 0.14-44.67). Conclusion: In addition to the traditional risk factors, IVF-ET and current IUD use play dominant roles in the occurrence of EP. Attention should be given to women with tubal infertility who have undergone IVE-ET treatment. - Background Ectopic pregnancy (EP) is the leading cause of maternal death during the first trimester of pregnancy, accounting for approximately 10 % of all pregnancy-related deaths [1]. It remains to be a condition presenting as a serious health problem for women of childbearing age [2]. It has been shown to reduce subsequent fertility and increase the chances of subsequent EP [3]. Over recent decades, there has been a rise in the incidence of EP [4]. There is extensive literature regarding the potential risk factors for EP. The identified risk factors for EP include age, previous EP, previous pelvic surgery, use of intrauterine devices (IUDs), female sterilization, history of pelvic inflammatory disease, history of infertility and smoking at the time of conception [5–12]. The increased awareness and knowledge on the risk factors for EP could enable an early and accurate diagnosis of the disease, resulting in a reduced need for surgery and fewer complications. However, the study designs of previous researches focused on women not using contraception at the time of conception to explore the risk factors for EP comprehensively, which failed to evaluate the association © 2015 Li et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in (...truncated)


This is a preview of a remote PDF: http://www.biomedcentral.com/content/pdf/s12884-015-0613-1.pdf

Cheng Li, Wei-Hong Zhao, Qian Zhu, Shu-Jun Cao, Hua Ping, Xiaowei Xi, Guo-Juan Qin, Ming-Xing Yan, Duo Zhang, Jun Qiu, Jian Zhang. Risk factors for ectopic pregnancy: a multi-center case-control study, BMC Pregnancy and Childbirth, 2015, pp. 187, 15, DOI: 10.1186/s12884-015-0613-1