The birth weight and placental weight percentile values of newborns with different genders and gestational weeks in Guangxi and comparing them with the current standards

WEI Hong-wei; MIAO Li-mei; QIN Yu-qin

doi:10.3969/j.issn.1674-3806.2023.12.15

Abstract：Objective To compare the birth weight and placental weight percentile values of newborns with different genders and gestational weeks in Guangxi,and to compare them with the current standards and to plot the per-centile curves.Methods A total of 11 731 singleton pregnancies delivered in Maternity and Child Health Care Hos-pital of Guangxi Zhuang Autonomous Region during May 2019 and December 2021 were collected.The birth weight and placental weight percentile curves of the newborns with different genders and gestational weeks were plotted using gen-eralized additive models for location,scale and shape(GAMLSS)package in R software,and their percentile values were specified and compared with the China's current standard and the international reference standard.Results The birth weight and placental weight percentile curves of newborns with different genders and gestational weeks in Guangxi and their percentile values were obtained,including 6264 male newborns and 5467 female newborns.With the increase of gestational weeks,the birth weight and placental weight of the newborns increased gradually,but the percentile values of the placental weight increased gently.Compared with those in the China current standard,the 10th percentiles(P10)of the newborns'birth weight in Guangxi were large during 31 and 38 weeks of gestation,and were small during 39 and 41 weeks of gestation.Similarly,compared with those in the China current standard,the90th percentiles(P90)of the newborns'birth weight in Guangxi were large during 34 and 37 weeks of gestation,and were small during 38 and 41 weeks of gestation.For 33 to 41 weeks of gestation,the P10 value of birth weight of the newborns in Guangxi was higher than that in the international reference standard,while the P90 value of birth weight of the newborns in Guangxi was lower than that in the international reference standard.The developmental peak of placenta in male fetuses occurred earlier than that in female fetuses.Conclusion The percentile values of the newborns'birth weight in Guangxi are different from those in the current standards.The local standards should be adopted to plot the relevant scales to avoid diagnostic bias.In addition,the kinetics of placental development are also related to fetal genders.