Association between progesterone only emergency contraceptive pill and ectopic pregnancy

Abstract

Introduction: Ectopic pregnancy remains a significant cause of morbidity and mortality in the developing world, with mortality being 10 times higher in developing world compared to the developed countries. Diagnosis in the resource constrained countries requires a high index of suspicion based on possible risk factors in the affected individual for early treatment to reduce mortality and morbidity associated with late diagnosis. Emergency contraceptive pills significantly lower the chances of an unwanted pregnancy following unprotected coitus in the mid cycle, and consequently reduce unsafe abortions. Awareness on correct use of the emergency pills remains poor. Several cases of tubal ectopic pregnancy following the use of emergency contraceptive pill use have been reported, with majority supposedly due to incorrect use of the pill. This forms the basis of this study. Objective: To identify if use of emergency contraceptive pill predisposes to ectopic pregnancy and assess other risk factors for ectopic pregnancy. Study setting: This study was conducted at the Kenyatta National Hospital in the acute gynaecology ward, antenatal wards and antenatal clinics. Methods: This was a case-control study matched for age. Consecutive sampling was used Women diagnosed with ectopic pregnancy were recruited as the cases (n= 120). Women with intrauterine pregnancy were recruited as matched controls at a ratio of 1:1.Data was analysed using SPSS software (version 18.0). Multivariate logistic regression analysis was performed to calculate the odds ratios (OR) and the corresponding 95% confidence intervals (CI). Results: Of the 120 cases and 120 controls recruited, 27.5% of the cases and 2.5% of the controls had taken Levonogesterol emergency contraceptive (LNG-EC) pill during the menstrual cycle leading to the current pregnancy. Of the cases, 72.7% took the LNG-EC within 24hrs after coitus, while all the controls took the pill within 24-48 hrs. Only 18.2% of the cases knew their fertile days. Majority of the cases (78.8%) swallowed both pills at once, and most women amongst the cases (n=24) and all the controls (n=3) took the pill in the secretory phase of their cycle. The risk of ectopic pregnancy (EP) increased 12-fold in women who had used LNG-EC (OR=12.44, 95% CI 3.1-49.84) after adjusting for other confounders. EP was associated with early sexual debut (p= 0.039), history of subfertility/infertility (OR=6.87, 95% CI 2.14-22.03). xiii Unplanned pregnancies were significantly associated with EP (p= ≤ 0.001). Previous treatment for STIs increased the risk of EP 3-fold (OR=3.01, 95% CI 1.45-6.21). Conclusion: Failed POEC increases the risk of ectopic pregnancy. Early sexual debut, infertility/subfertility and previous STIs are significant risk factors for ectopic pregnancy. Recommendation: POEC should be recognized as a risk factor for ectopic pregnancy and included in the client information leaflet in the drug packaging. Client education at the point of sale using information, education and communication (IEC) materials and advice on when to seek medical attention