Griffiths P D, Ronalds C J, Heath R B
J Epidemiol Community Health. 1980 Jun;34(2):124-8. doi: 10.1136/jech.34.2.124.
Serological evidence of infection with influenza A and B viruses was sought during three successive winters. Paired sera from 1595 pregnant women were studied and 79 infections occurred in 77 women (4.8%). A further 77 women who had no serological evidence of recent influenza infection were selected from the study population to serve as a control group. Cases and controls were comparable with respect to age, race, marital status, and number of previous pregnancies. Their offspring had virtually identical mean birth weights, skull circumferences, lengths, and incidences of neonatal jaundice. Although all the infections occurred in either the second or the third trimesters of pregnancy, the cases delivered more babies with congenital abnormalities than did the controls. The possibility was considered that the presence of an abnormal fetus made these women more susceptible to influenza infection. Unexpectedly, the women experiencing influenza infection during pregnancy delivered an excess of male babies, and an excess of females was born to the controls. Although this difference was statistically highly significant (P < 0.01), a biological explanation for the results was not readily apparent and it is suggested that future studies of influenza during pregnancy should particularly look for evidence of an altered sex ratio.
在连续三个冬季期间，对甲型和乙型流感病毒感染的血清学证据进行了探寻。对1595名孕妇的配对血清进行了研究，77名女性（4.8%）出现了79次感染。从研究人群中另外选取了77名近期无流感感染血清学证据的女性作为对照组。病例组和对照组在年龄、种族、婚姻状况和既往妊娠次数方面具有可比性。他们的后代在平均出生体重、头围、身长和新生儿黄疸发生率方面几乎相同。尽管所有感染均发生在妊娠的第二或第三个月，但病例组分娩的先天性异常婴儿比对照组更多。曾考虑过异常胎儿的存在使这些女性更容易感染流感这一可能性。出乎意料的是，孕期感染流感的女性所生的男婴过多，而对照组所生的女婴过多。尽管这种差异在统计学上具有高度显著性（P < 0.01），但该结果的生物学解释并不明显，建议未来关于孕期流感的研究应特别寻找性别比例改变的证据。
