上海地区足月新生儿肛门生殖器距离的正常范围测定和影响因素分析

Determination of the normal range of anogenital distance in full-term neonates in Shanghai and analysis of influencing factors

目的建立足月新生儿肛门生殖器距离(AGD)的正常参考值,并探讨可能影响新生儿AGD的相关因素。方法选取2017年11月至2019年3月在上海交通大学医学院附属瑞金医院分娩的胎龄≥37周的新生儿,收集母亲和新生儿的一般资料信息,测量新生儿AGD数据。认定男性肛门中心至阴囊基底部的距离即为男性AGD,女性肛门中心至阴唇后联合的距离即为女性AGD。分析母亲和新生儿自身因素对新生儿AGD的影响。结果共纳入1078例新生儿。其中男586例,女492例。男性AGD[(22.90±3.80)mm]大于女性AGD[(11.80±2.10)mm],差异有统计学意义(t=22.316,P<0.05)。单胎新生儿AGD大于双胎新生儿AGD,差异有统计学意义[男性:(23.01±3.82)mm比(21.18±1.88)mm;女性:(11.89±2.08)mm比(10.98±1.75)mm,t=26.185、18.326,均P<0.05)]。新生儿的胎龄、出生体质量、头围和身长与AGD均有相关性(均P<0.05)。母亲的年龄、身高、体质量、身体质量指数、孕次、产次及职业等与新生儿AGD均无相关性(均P>0.05)。10例生殖器畸形男性新生儿AGD明显小于生殖器外观正常者[(22.89±1.99)mm比(23.55±3.78)mm],差异有统计学意义(t=15.362,P=0.006)。结论上海地区足月男性和女性新生儿AGD的参考值分别为(22.90±3.80)mm和(11.80±2.10)mm,新生儿的胎龄、出生体质量、头围和身长可能是影响新生儿AGD的内在因素。

Objective To provide a normal reference range for anogenital distance(AGD)in full-term neonates and to investigate factors possibly affecting neonatal AGD.Methods Neonates with gestational age≥37 weeks who were delivered in the Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from November 2017 to March 2019 were enrolled.General information on mothers and newborns were collected and neonatal AGD were measured.The distance from the male anus center to the base of the scrotum was determined to be the male AGD,and the distance from the female anus center to the posterior labia was recorded as the female AGD.The effects of maternal and neonatal factors on neonatal AGD were analyzed.Results A total of 1078 newborns were included,including 586 males and 492 females.Male AGD[(22.90±3.80)mm]was significantly greater than female AGD[(11.80±2.10)mm](t=22.316,P<0.05).The AGD of singleton neonates was significantly greater than that of neonatal twins[males:(23.01±3.82)mm vs.(21.18±1.88)mm,females:(11.89±2.08)mm vs.(10.98±1.75)mm,t=26.185,18.326,all P<0.05].Neonatal gestational age,birth weight,head circumference and length were significantly associated with AGD(all P<0.05).Maternal factors(including age,height,weight,body mass index,gravidity,parity,occupation,etc.)were not significantly associated with neonatal AGD(all P>0.05).The AGD of 10 children with genital malformation was significantly smaller than that of males with normal genital appearance[(22.89±1.99)mm vs.(23.55±3.78)mm](t=15.362,P=0.006).Conclusions The reference ranges of AGD in full-term males and females in Shanghai are(22.90±3.80)mm and(11.80±2.10)mm,respectively.The neonatal gestational age,birth weight,head circumference and length may be the intrinsic factors affecting neonatal AGD.