Khoury M J, Marks J S, McCarthy B J, Zaro S M
Am J Obstet Gynecol. 1985 Mar 15;151(6):777-82. doi: 10.1016/0002-9378(85)90518-6.
We investigated factors affecting the sex differential in neonatal mortality rate using linked birth and death certificates of more than 300,000 infants born in Georgia between 1974 and 1977. The neonatal mortality rate was higher in male infants than in female infants (relative risk = 1.23, p less than 10(-8)) and was most pronounced for infants weighing between 1501 and 2500 gm (relative risk = 1.78, p less than 10(-8)). This differential persisted after adjustment was made for effects of several prenatal and labor-related factors. The male excess in neonatal mortality rate was most prominent during the first week of life and was found for several perinatal disorders. Respiratory distress syndrome-related mortality showed the largest male excess (relative risk = 1.57, p less than 10(-8)) and was most pronounced in infants weighing between 1501 and 2500 gm (relative risk = 2.78, p less than 10(-8)), in whom it accounted for roughly 60% of the excess. Since previous studies have shown that male infants have a higher incidence of respiratory distress syndrome but not a higher case-fatality rate, we suggest that slower lung maturation among male fetuses is a major contributing factor to the sex differential in neonatal mortality.
我们利用1974年至1977年在佐治亚州出生的30多万名婴儿的出生证明和死亡证明进行关联，调查了影响新生儿死亡率性别差异的因素。男婴的新生儿死亡率高于女婴（相对风险=1.23，p<10^(-8)），在体重为1501至2500克的婴儿中最为明显（相对风险=1.78，p<10^(-8)）。在对几个产前和分娩相关因素的影响进行调整后，这种差异仍然存在。新生儿死亡率中的男性过高现象在出生后的第一周最为突出，并且在几种围产期疾病中都有发现。与呼吸窘迫综合征相关的死亡率显示出最大的男性过高现象（相对风险=1.57，p<10^(-8)），在体重为1501至2500克的婴儿中最为明显（相对风险=2.78，p<10^(-8)），其中约60%的过高现象由此导致。由于先前的研究表明男婴患呼吸窘迫综合征的发生率较高，但病死率并不高，我们认为男性胎儿肺部成熟较慢是新生儿死亡率性别差异的一个主要促成因素。
