胎头生长情况的描述大多来自横向的观察资料,故临床常不可靠,甚至当人群中胎头生长情况比较一致时,具有不同生长特点的亚组也只能用纵向资料及合适的技术分析来确定。作者利用系列超声对受测孕妇从13孕周至38孕周由专人每隔3周测量胎头双顶径一次,取得纵向资料,用以观察不同性别、不同出生体重组的胎头生长情祝,了解男、女胎头生长曲线的差异。因孕龄的准确性至关重要,研究对象只限于预产期7天内分娩的病人。考虑到月经周期的变异,预产期从末次月经第一天起按280天计。仔细询问每位患者末次月经前一年的月经情况,计算每例最长 The description of fetal head growth is mostly from lateral observation data, so the clinical often unreliable, even when the fetal head growth in the population more consistent, with different growth characteristics of subgroups can only use longitudinal data and appropriate technical analysis to determine. The authors used serial ultrasound to measure fetal head biparietal diameter once every three weeks from 13th week of gestation to 38th week of gestation to obtain the longitudinal data to observe the growth of fetal head in different gender and different birth weight groups. Understanding of male and female fetal head growth curve differences. Due to the accuracy of gestational age is crucial, the study was limited to the delivery of patients within 7 days of the expected date of delivery. Taking into account the variation of the menstrual cycle, the expected date of birth from the first day of the last menstruation by 280 days. Carefully ask each patient last menstrual menstruation a year ago, calculate the longest in each case