Personality Type Linked to Fertility

Personality may influence fertility in the absence of birth control, according to a new study of men and women in Senegal. The research, reported in the Proceedings of the National Academy of Sciences, showed that extroverted men and neurotic women were more likely to produce offspring.

Extroverted men are more likely to have high social status according to the researchers including Professor Virpi Lummaa. This phenomenon has been demonstrated in western cultures including the U.S. and Europe. Men of high social status generally have more opportunities for sex within and outside of marriage, which presumably increases the chance of pregnancy. This is particularly true in a polygamous society as in Senegal, where use of contraceptives is rare. However, Dr. Lummaa theorized that this link between extroversion and higher number of children could exist in all cultures.

Women who are needy, anxious, moody and depressed were characterized as neurotic in the study. Such women sought sex more frequently, perhaps due to an attachment anxiety, according to the authors from Sheffield University in the U.K. The women may have sex more often as a way to feel close to another person, or to compete with other wives in a polygamous society.

In western culture, neurotic women tend to have fewer children and to die at a younger age.

While the researchers assume that more frequent sex causes higher levels of fertility in Senegal, the study did not attempt to measure how often the participants had sex – only the number of children was measured. It is possible that another factor made sexual encounters between extroverted men and neurotic women more fruitful.

Some observers have suggested that having more children caused the women’s neuroticism, but Dr. Lummaa disagrees. He notes that the older women were not more neurotic even though on average they had more children. This demonstrates that neuroticism was independent of fertility, or the cause of it.

The study also showed that the children of a neurotic mother were more likely to be malnourished and underfed, with a lower body mass index. Dr. Lummaa studied 65 family units in four villages in Senegal for about one month.

By Joni Holderman, [email protected], contributing reporter for Mental Health News.