Parazzini F, Tozzi L, Ferraroni M, Bocciolone L, La Vecchia C, Fedele L
Istituto di Ricerche Farmacologiche Mario Negri, II Clinica Ostetrico-Ginecologica, Università di Milano, Italy.
Obstet Gynecol. 1992 Nov;80(5):821-6.
To analyze risk factors for ectopic pregnancy in a population at low risk for the disease.
Between September 1989 and February 1991 in Milan, we conducted a case-control study on 120 cases of ectopic pregnancy and 209 controls. The control subjects gave birth at term (more than 37 weeks' gestation) to healthy infants on randomly selected days at the same hospitals where the cases had been identified.
The risk of ectopic gestation was about 40% higher in smokers than in controls, and the risk estimates increased with the number of cigarettes smoked per day (chi 2(1) trend 4.21, P = .04) and the duration of smoking (chi 2(1) trend 7.31, P < .01). However, smoking was not associated with the risk of ectopic pregnancy after adjustment for potential confounding factors (including history of pelvic inflammatory disease) in a multivariate analysis (relative risks [RRs] for ten or fewer and more than ten cigarettes per day versus no smoking were 0.8 and 1.1, respectively; chi 2(1) trend 0.10, P = not significant). Infertility problems or difficulty in conception were reported by 32% of the cases and 10% of the controls; the corresponding multivariate RR was 4.7 (95% confidence interval [CI] 2.3-9.5). A history of abdominal surgery was associated with about double the risk of ectopic pregnancy (multivariate RR 2.4, 95% CI 1.4-4.2). Similar estimates were found when the analysis was performed considering various types of surgery separately such as appendectomy, cesarean delivery, and other abdominal surgery. Finally, the risk of ectopic pregnancy was higher in women reporting a history of pelvic inflammatory disease (RR 2.7, 95% CI 0.9-8.7) and increased with the number of sexual partners (chi 2(1) trend 4.51, P = .03).
Problems of infertility or difficulties in conception, history of pelvic inflammatory disease/salpingitis, and abdominal surgery are the main risk factors for ectopic pregnancy in this Italian study. Sexual habits also appear to have some independent effect.
分析低风险人群中异位妊娠的危险因素。
1989年9月至1991年2月期间，在米兰，我们对120例异位妊娠病例和209例对照进行了一项病例对照研究。对照对象在与病例确诊医院相同的医院中，于随机选定的日期足月分娩（妊娠超过37周）健康婴儿。
吸烟者发生异位妊娠的风险比对照组高约40%，风险估计值随每日吸烟量（χ²(1)趋势4.21，P = 0.04）和吸烟持续时间（χ²(1)趋势7.31，P < 0.01）增加而升高。然而，在多因素分析中对潜在混杂因素（包括盆腔炎病史）进行调整后，吸烟与异位妊娠风险无关（每天吸烟十支及以下和超过十支与不吸烟相比的相对风险[RRs]分别为0.8和1.1；χ²(1)趋势0.10，P = 无显著性差异）。32%的病例和10%的对照报告有不孕问题或受孕困难；相应的多因素RR为4.7（95%置信区间[CI] 2.3 - 9.5）。腹部手术史与异位妊娠风险约增加一倍相关（多因素RR 2.4，95% CI 1.4 - 4.2）。当分别考虑各种类型的手术如阑尾切除术、剖宫产和其他腹部手术进行分析时，得到了类似的估计值。最后，报告有盆腔炎病史的女性发生异位妊娠的风险更高（RR 2.7，95% CI 0.9 - 8.7），且随性伴侣数量增加而升高（χ²(1)趋势4.51，P = 0.03）。
在这项意大利研究中，不孕问题或受孕困难、盆腔炎/输卵管炎病史以及腹部手术是异位妊娠的主要危险因素。性行为习惯似乎也有一些独立影响。
