Rowett Institute, University of Aberdeen, Aberdeen, AB25 2ZD, UK.
Biomathematics & Statistics Scotland, Aberdeen, AB25 2ZD, UK.
J Dev Orig Health Dis. 2020 Aug;11(4):350-359. doi: 10.1017/S2040174419000576. Epub 2019 Oct 7.
Placental weight is a valuable indicator of its function, predicting both pregnancy outcome and lifelong health. Population-based centile charts of weight-for-gestational-age and parity are useful for identifying extremes of placental weight but fail to consider maternal size. To address this deficit, a multiple regression model was fitted to derive coefficients for predicting normal placental weight using records from healthy pregnancies of nulliparous/multiparous women of differing height and weight (n = 107,170 deliveries, 37-43 weeks gestation). The difference between actual and predicted placental weight generated a z-score/individual centile for the entire cohort including women with pregnancy complications (n = 121,591). The association between maternal BMI and placental weight extremes defined by the new customised versus population-based standard was investigated by logistic regression, as was the association between low placental weight and pregnancy complications. Underweight women had a greater risk of low placental weight [<10thcentile, OR 1.84 (95% CI 1.66, 2.05)] and obese women had a greater risk of high placental weight [>90th centile, OR 1.98 (95% CI 1.88, 2.10)] using a population standard. After customisation, the risk of high placental weight in obese/morbidly obese women was attenuated [OR 1.17 (95% CI 1.09, 1.25)]/no longer significant, while their risk of low placental weight was 59%-129% higher (P < 0.001). The customised placental weight standard was more closely associated with stillbirth, hypertensive disease, placental abruption and neonatal death than the population standard. Our customised placental weight standard reveals higher risk of relative placental growth restriction leading to lower than expected birthweights in obese women, and a stronger association between low placental weight and pregnancy complications generally. Further, it provides an alternative tool for defining placental weight extremes with implications for the placental programming of chronic disease.
胎盘重量是其功能的一个有价值的指标，可以预测妊娠结局和终生健康。基于人群的体重与胎龄和产次百分位图表对于识别胎盘重量的极端情况很有用，但未能考虑到产妇的体型。为了解决这一缺陷，我们使用不同身高和体重的初产妇/经产妇的健康妊娠记录（n = 107170 例，37-43 周妊娠），拟合了一个多元回归模型，以预测正常胎盘重量的系数。实际胎盘重量与预测胎盘重量之间的差异为整个队列（包括患有妊娠并发症的妇女，n = 121591 例）生成了一个 z 分数/个体百分位。使用新的定制标准与基于人群的标准定义的胎盘重量极端情况与母亲 BMI 的关联以及低胎盘重量与妊娠并发症的关联通过逻辑回归进行了研究。使用人群标准，体重不足的妇女发生低胎盘重量[<10 百分位，OR 1.84（95%CI 1.66，2.05）]的风险更高，肥胖妇女发生高胎盘重量[>90 百分位，OR 1.98（95%CI 1.88，2.10）]的风险更高。在定制化之后，肥胖/病态肥胖妇女高胎盘重量的风险减弱[OR 1.17（95%CI 1.09，1.25）]/不再显著，而她们低胎盘重量的风险则高出 59%-129%（P < 0.001）。与基于人群的标准相比，定制的胎盘重量标准与死胎、高血压疾病、胎盘早剥和新生儿死亡的关联更为密切。我们定制的胎盘重量标准揭示了肥胖妇女相对胎盘生长受限的风险更高，导致出生体重低于预期，并且低胎盘重量与妊娠并发症之间的关联更强。此外，它为定义胎盘重量极端情况提供了另一种工具，这对慢性疾病的胎盘编程具有重要意义。
