Your DNA Can Tell How Many Kids You'll Have

The age at which you will have your first child and the number of kids you are likely to have may be encoded in your DNA, say scientists who found that genetic data can be used to accurately predict our reproductive behavior. The study, led by researchers at University of Oxford, includes an analysis of 62 datasets with information from 2,38,064 men and women on the age at which they had their first child and 3,30,000 men and women for the number of children. Until now, reproductive behavior was thought to be linked to personal choices or social circumstance. Researchers also found that women with DNA variants for postponing parenthood also have bits of DNA code associated with later onset of menstruation and later menopause. The study shows that DNA variants linked with the age at which people have their firstborn are also associated with characteristics reflecting reproduction and sexual development, such as the age at which girls have their first period, when the voice breaks in boys and at what stage women experience their menopause.