Puskarczyk Karolina, Galbarczyk Andrzej, Klimek Magdalena, Nenko Ilona, Odrzywołek Ludwik, Jasienska Grazyna
Department of Environmental Health, Faculty of Health Sciences, Jagiellonian University Medical College, 31-531, Krakow, Poland.
Am J Hum Biol. 2015 Sep-Oct;27(5):731-3. doi: 10.1002/ajhb.22710. Epub 2015 Mar 25.
The aim of the present study is to examine whether being born after a brother versus after a sister differentially impacts reproductive outcomes in a contemporary population. The sex of the preceding sibling may influence an individual's fitness, and, in fact, individuals born after a brother have been shown to have lower reproductive success in historical populations. Males, as the more expensive sex, constitute a drain on maternal resources and elicit an immune response during pregnancy, which may have negative consequences on subsequent siblings.
A questionnaire was used to collect data on reproductive health and family history from 951 women and 380 men between 20 and 92 years of age in villages throughout the Mogielica Human Ecology Study Site in southern Poland. Number of children, number of sons and daughters, age at menarche, age at marriage, age at menopause, and age at first and last reproduction were tested as components of reproductive success.
The sex of one's preceding sibling had no statistically significant impact on any of the reproductive characteristics tested.
Our results suggest that potential immunological and nutritional disadvantages experienced during prenatal life by individuals born after male siblings do not have long-lasting effects in modern, well-nourished populations.
本研究旨在探讨在当代人群中，出生在哥哥之后与出生在姐姐之后对生殖结局是否有不同影响。前一个兄弟姐妹的性别可能会影响个体的健康状况，事实上，在历史人群中，出生在哥哥之后的个体生育成功率较低。男性作为成本更高的性别，会消耗母体资源，并在孕期引发免疫反应，这可能会对后续的兄弟姐妹产生负面影响。
通过问卷调查，收集了波兰南部莫吉列察人类生态研究站点各村951名年龄在20至92岁之间的女性和380名男性的生殖健康和家族史数据。对子女数量、儿子和女儿的数量、初潮年龄、结婚年龄、绝经年龄以及首次和末次生育年龄进行测试，作为生殖成功率的组成部分。
前一个兄弟姐妹的性别对所测试的任何生殖特征均无统计学上的显著影响。
我们的结果表明，在现代营养良好的人群中，出生在男性兄弟姐妹之后的个体在产前可能经历的潜在免疫和营养劣势不会产生长期影响。
