Department of Gynaecology, Rigshospitalet, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Institute of Statistics, Ulm University, Ulm, Germany.
Am J Obstet Gynecol. 2019 May;220(5):478.e1-478.e15. doi: 10.1016/j.ajog.2019.02.014. Epub 2019 Feb 11.
By being noninvasive, medical termination of pregnancy has increased worldwide access to abortion and improved safety of unsafe abortion. However, secondary surgical intervention is the most frequent complication to medical abortion.
We aimed to identify and quantify risk factors for surgical intervention in women undergoing medically induced termination of pregnancy before 9 completed weeks of gestation.
We conducted a nationwide cohort study, including all pregnancies terminated before 63 gestational days in women aged 15-49 years during the period 2005-2015. Induction regimen was 200 mg mifepristone followed 24-48 hours later by 0.8 mg vaginal misoprostol. All included pregnancies were followed up for 8 weeks from mifepristone administration. Data were retrieved from national health registers. Multiple logistic regression provided adjusted odds ratios of surgical intervention with 95% confidence intervals. The discriminative ability of the risk factors in identifying surgical intervention was assessed by cross-validated area under the receiver operating characteristic curve.
Of 86,437 early medical abortions, 5320 (6.2%) underwent a surgical intervention within 8 weeks after induction. The proportion of surgical interventions increased from 3.5% in the 5th to 6th gestational week to 10.3% in week 9, odds ratio, 3.2 (95% confidence interval, 2.9-3.6). Compared with women aged 15-19 years, the risk of surgical intervention increased with increasing maternal age until the age of 30-34 years, odds ratio, 1.7 (95% confidence interval, 1.5-1.9), where after the risk decreased to an odds ratio for age group 40-49 of 1.2 (95% confidence interval, 1.0-1.4). Compared with nulliparous women, a history of only vaginal deliveries with spontaneous delivery of placenta implied an odds ratio of 1.1 (95% confidence interval, 1.0-1.2), women with a history of at least 1 cesarean delivery, an odds ratio of 1.5 (95% confidence interval, 1.3-1.6), and women having experienced a manual removal of placenta after a vaginal birth, an odds ratio of 2.0 (95% confidence interval, 1.7-2.4). Previous medically induced abortion decreased the risk of surgical intervention, odds ratio 0.84 (95% confidence interval, 0.78-0.91), whereas previous early (before 56 days of gestation) surgically induced abortion implied a 53% (95% confidence interval, 1.4-1.7) increased risk of surgical intervention. Previous surgical abortion after 55 days of gestation increased the risk by 17% (95% confidence interval, 1.1-1.3). The area under the receiver operating characteristic curve of the model including all quantified risk factors was 63% (95% confidence interval, 62-64%).
Gestational age, maternal age, previous deliveries, and history of medically and surgically induced abortions all had a significant influence on the risk of surgical intervention of early medical abortion. However, inclusion of all quantified risk factors still left most interventions unpredictable.
通过非侵入性方式，终止妊娠的医疗方法增加了全球范围内获取堕胎的机会，并提高了不安全堕胎的安全性。然而，二次手术干预是药物流产最常见的并发症。
我们旨在确定并量化在妊娠 9 周前接受药物诱导终止妊娠的女性中进行手术干预的风险因素。
我们进行了一项全国性队列研究，包括在 2005 年至 2015 年期间 15 至 49 岁女性中妊娠 63 天内终止的所有妊娠。诱导方案为 200mg 米非司酮，24-48 小时后阴道给予 0.8mg 米索前列醇。所有纳入的妊娠均在米非司酮给药后 8 周内进行随访。数据从国家健康登记处检索。多因素逻辑回归提供了 95%置信区间的调整比值比。通过交叉验证的接收者操作特征曲线下面积评估了风险因素识别手术干预的能力。
在 86437 例早期药物流产中，5320 例（6.2%）在诱导后 8 周内进行了手术干预。手术干预的比例从第 5 至 6 孕周的 3.5%增加到第 9 孕周的 10.3%，比值比为 3.2（95%置信区间，2.9-3.6）。与 15-19 岁的女性相比，随着产妇年龄的增加，手术干预的风险增加，直到 30-34 岁，比值比为 1.7（95%置信区间，1.5-1.9），此后，年龄组 40-49 岁的风险降低至 1.2（95%置信区间，1.0-1.4）。与未生育的女性相比，只有阴道分娩且胎盘自然娩出的病史意味着比值比为 1.1（95%置信区间，1.0-1.2），至少有 1 次剖宫产史的女性比值比为 1.5（95%置信区间，1.3-1.6），而经历过阴道分娩后手动胎盘剥离的女性比值比为 2.0（95%置信区间，1.7-2.4）。既往药物流产可降低手术干预的风险，比值比为 0.84（95%置信区间，0.78-0.91），而既往早期（妊娠 56 天前）手术流产则意味着手术干预的风险增加 53%（95%置信区间，1.4-1.7）。妊娠 55 天后的既往手术流产增加了 17%（95%置信区间，1.1-1.3）的风险。包括所有量化风险因素的模型的受试者工作特征曲线下面积为 63%（95%置信区间，62-64%）。
妊娠周数、产妇年龄、既往分娩史和药物及手术流产史均对早期药物流产手术干预的风险有显著影响。然而，纳入所有量化风险因素仍然使大多数干预措施不可预测。
