Buekens P, Delvoye P, Wollast E, Robyn C
J Epidemiol Community Health. 1984 Mar;38(1):79-80. doi: 10.1136/jech.38.1.79.
A group of women with unknown last menstrual period was studied representing 16% of a total of 22 404 pregnant women recorded using a common perinatal form. Unknown menstrual period is associated with high rates of low birth weight and with low socioeconomic and sociodemographic status. Such characteristics are also associated with a high rate of preterm deliveries. Thus any possible bias introduced in studies of prematurity by ignoring the group of women with unknown last menstrual period should be carefully checked.
对一群末次月经时间不明的女性进行了研究，她们占使用通用围产期表格记录的22404名孕妇总数的16%。月经时间不明与低出生体重的高发生率以及低社会经济和社会人口学状况相关。这些特征也与早产的高发生率相关。因此，在早产研究中因忽略末次月经时间不明的女性群体而引入的任何可能偏差都应仔细核查。
