There is growing evidence of sex differences in placental vascular development. The objective of this study was to investigate the effect of fetal sex on uterine artery pulsatility index (PI) throughout gestation in a cohort of normal and complicated pregnancies. A prospective longitudinal study was conducted in 240 pregnant women. Pulsed wave Doppler ultrasound of the proximal uterine arteries was performed at a 4-weekly interval between 14 and 40 weeks of gestation. The patients were classified retrospectively as normal or complicated (one or more of maternal preeclampsia, preterm birth, or small for gestational age). To assess if the change in uterine artery PI during gestation differed between normal and complicated pregnancies and between fetal sexes, the uterine artery PI was modeled using a linear function of gestational age and the rate of change was estimated from the slope. While the uterine artery PI did not differ over gestation between females and males for normal pregnancies, the trajectory of this index differed by fetal sex for pregnancies complicated by either preeclampsia, preterm birth, or fetal growth restriction (p < 0.0001). The male fetuses in the complicated pregnancy group had an elevated slope compared to the other groups (p < 0.0001), suggesting a more progressive deterioration in uteroplacental perfusion over gestation. The uterine artery PI is widely used to assess uteroplacental function in clinical settings. The observation that this metric changes more rapidly in complicated pregnancies where the fetus was male highlights the importance of sex when interpreting hemodynamic markers of placental maturation.

中文翻译：

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妊娠合并胎盘功能障碍的妊娠期子宫动脉多普勒性别差异


越来越多的证据表明胎盘血管发育存在性别差异。本研究的目的是在一组正常和复杂妊娠中调查胎儿性别对整个妊娠期间子宫动脉搏动指数（PI）的影响。对 240 名孕妇进行了一项前瞻性纵向研究。在妊娠 14 至 40 周之间，每 4 周进行一次近端子宫动脉脉冲波多普勒超声检查。回顾性地将患者分类为正常或复杂（孕妇先兆子痫、早产或小于胎龄中的一种或多种）。为了评估妊娠期间子宫动脉 PI 的变化在正常妊娠和复杂妊娠之间以及胎儿性别之间是否存在差异，使用胎龄的线性函数对子宫动脉 PI 进行建模，并根据斜率估计变化率。虽然正常妊娠时女性和男性的子宫动脉 PI 在整个妊娠过程中没有差异，但对于并发先兆子痫、早产或胎儿生长受限的妊娠，该指数的轨迹因胎儿性别而异 (p < 0.0001)。与其他组相比，复杂妊娠组中的男性胎儿的斜率升高（p < 0.0001），表明妊娠期间子宫胎盘灌注更加恶化。子宫动脉 PI 广泛用于临床环境中评估子宫胎盘功能。在胎儿为男性的复杂妊娠中，这一指标变化更快，这一观察结果凸显了性别在解释胎盘成熟的血流动力学标志物时的重要性。