Epidemiology Branch, Division of Intramural Population Health Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, MD.
Department of Epidemiology, University of Pittsburgh, Pittsburgh, PA.
Am J Obstet Gynecol. 2020 Oct;223(4):570.e1-570.e14. doi: 10.1016/j.ajog.2020.04.002. Epub 2020 Apr 10.
Although nausea and vaginal bleeding are commonly experienced in early pregnancy, their prognostic value in predicting clinical pregnancy loss is not well understood.
This study aimed to understand whether timing of bleeding and nausea symptoms can be used to predict risk of pregnancy loss among women with ultrasound-confirmed pregnancies.
A cohort of 701 women with clinically confirmed pregnancies and 1 to 2 previous pregnancy losses were preconceptionally enrolled in the Effects of Aspirin in Gestation and Reproduction trial (2006-2012). Participants completed daily symptom diaries from 2 to 8 weeks' gestation and were prospectively monitored for detection of pregnancy loss. The risk of pregnancy loss was estimated for each observed bleeding and nausea pattern, and positive and negative predictive values for each pattern were calculated.
Among 701 women, 211 (30.1%) reported any vaginal bleeding, and 639 (91.2%) reported any nausea. Most bleeding experienced by women was spotting and contained within a single episode. Within 2 to <4, 4 to <6, and 6 to 8 weeks' gestation, vaginal bleeding occurred in 5.9% (41) (5.7% live birth, 7.1% clinical pregnancy loss), 14.6% (102) (13.9% live birth, 18.6% clinical pregnancy loss), and 20.8% (146) (18.4% live birth, 32.4% clinical pregnancy loss) of women, respectively. Within the same gestational periods, nausea was reported in 22.7% (159) (23.2% live birth, 20.4% clinical pregnancy loss), 65.9% (462) (67.5% live birth, 58.4% clinical pregnancy loss), and 87.0% (610) (90.6% live birth, 69.0% clinical pregnancy loss) of women. Women who had bleeding without nausea between 6 and 8 weeks' gestation (3.6% prevalance) had the greatest risk of clinical pregnancy loss (risk difference=56.1%; 95% confidence interval, 37.6-74.7), a positive predictive value of 68.0% (49.7%, 86.3%), negative predictive value of 85.8% (83.2%, 88.4%), positive likelihood ratio of 11.1 (2.04, 20.1), and negative likelihood ratio of 0.86 (0.79, 0.93). Nausea and bleeding are clinical factors that predicted clinical pregnancy loss (area under the curve, 0.87; 95% confidence interval, 0.81-0.88) similar to age, body mass index, blood pressure, and waist-to-hip ratio (area under the curve, 0.81; 95% confidence interval, 0.78-0.88) measured preconceptionally.
Women experiencing bleeding without nausea between 6 and 8 weeks' gestation had an increased risk of clinical pregnancy loss. Bleeding and nausea were not predictive risk factors of clinical pregnancy loss prior to 6 weeks' gestation.
尽管恶心和阴道出血在早孕中很常见，但它们对预测临床妊娠丢失的预后价值尚不清楚。
本研究旨在了解出血和恶心症状的出现时间是否可用于预测经超声确认妊娠的女性发生妊娠丢失的风险。
一项队列研究纳入了 701 名有临床确诊妊娠且有 1 至 2 次既往妊娠丢失的女性（2006-2012 年）。参与者在妊娠 2 至 8 周时完成每日症状日记，并进行前瞻性监测以检测妊娠丢失。对每种观察到的出血和恶心模式的妊娠丢失风险进行了估计，并计算了每种模式的阳性和阴性预测值。
在 701 名女性中，211 名（30.1%）报告有任何阴道出血，639 名（91.2%）报告有任何恶心。大多数女性的出血为点状出血，且仅发生一次。妊娠 2 至<4 周、4 至<6 周和 6 至 8 周时，分别有 5.9%（41 例）（5.7%活产，7.1%临床妊娠丢失）、14.6%（102 例）（13.9%活产，18.6%临床妊娠丢失）和 20.8%（146 例）（18.4%活产，32.4%临床妊娠丢失）的女性出现阴道出血。在同一妊娠期间，22.7%（159 例）（23.2%活产，20.4%临床妊娠丢失）、65.9%（462 例）（67.5%活产，58.4%临床妊娠丢失）和 87.0%（610 例）（90.6%活产，69.0%临床妊娠丢失）的女性报告有恶心。妊娠 6 至 8 周时出现无恶心的出血（3.6%发生率）的女性临床妊娠丢失风险最高（风险差异=56.1%；95%置信区间，37.6-74.7%），阳性预测值为 68.0%（49.7%，86.3%），阴性预测值为 85.8%（83.2%，88.4%），阳性似然比为 11.1（2.04，20.1），阴性似然比为 0.86（0.79，0.93）。恶心和出血是预测临床妊娠丢失的临床因素（曲线下面积为 0.87；95%置信区间为 0.81-0.88），与妊娠前测量的年龄、体重指数、血压和腰臀比（曲线下面积为 0.81；95%置信区间为 0.78-0.88）相似。
妊娠 6 至 8 周时出现无恶心的出血的女性临床妊娠丢失风险增加。出血和恶心在妊娠 6 周前不是临床妊娠丢失的预测风险因素。
