Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Hofstra Northwell School of Medicine, North Shore University Hospital, Manhasset, New York.
Department of Obstetrics and Gynecology, Hofstra Northwell School of Medicine, North Shore University Hospital, Manhasset, New York.
Am J Perinatol. 2018 Nov;35(13):1235-1240. doi: 10.1055/s-0037-1618588. Epub 2018 Jan 10.
The objective of this study was to determine the effect, if any, of maternal body mass index (BMI) and amniotic fluid index (AFI) on the accuracy of sonographic estimated fetal weight (EFW) at 40 to 42 weeks' gestation.
This was a retrospective cohort study of singleton gestations with ultrasound performed at 40 to 42 weeks from 2010 to 2013. In this study, patients with documented BMI and sonographic EFW and AFI, concurrently, within 7 days of delivery were included. Chronic medical conditions and fetal anomalies were excluded from this study. The primary variable of interest was the rate of substantial error in EFW, defined as absolute percentage error (APE) >10%.
A total of 1,000 pregnancies were included. Overall, the APE was 6.0 ± 4.5% and the rate of substantial error was 17.4% ( = 174). There was no significant difference in APE or rate of substantial error between BMI groups. In the final multivariable logistic regression model, the rate of substantial error was increased in women with oligohydramnios (OR 1.79; 95% CI: 1.10-2.92). Furthermore, oligohydramnios was significantly more likely to overestimate EFW while polyhydramnios was more likely to underestimate EFW. Maternal BMI did not affect the accuracy of sonographic EFW.
Sonographic EFW may be affected by extremes of AFI in the postdates period. Maternal BMI does not affect EFW accuracy at 40 to 42 weeks.
本研究旨在确定母体体重指数（BMI）和羊水指数（AFI）对 40 至 42 孕周超声估计胎儿体重（EFW）准确性的影响。
这是一项回顾性队列研究，纳入了 2010 年至 2013 年期间 40 至 42 孕周进行超声检查的单胎妊娠。在这项研究中，纳入了同时在分娩前 7 天内记录了 BMI 和超声 EFW 和 AFI 的患者。本研究排除了慢性疾病和胎儿畸形。主要观察变量是 EFW 存在显著误差的发生率，定义为绝对百分比误差（APE）>10%。
共纳入 1000 例妊娠。总体而言，APE 为 6.0±4.5%，存在显著误差的发生率为 17.4%（=174）。BMI 组之间的 APE 或存在显著误差的发生率无显著差异。在最终的多变量逻辑回归模型中，羊水过少的孕妇存在显著误差的风险增加（OR 1.79；95%CI：1.10-2.92）。此外，羊水过少更可能高估 EFW，而羊水过多更可能低估 EFW。母体 BMI 并不影响超声 EFW 的准确性。
超声 EFW 可能受到过期妊娠时 AFI 极端值的影响。母体 BMI 不会影响 40 至 42 孕周时 EFW 的准确性。
