Women have hormonal cues for baby cuteness

Premenopausal women, especially those taking oral contraceptives, have an advantage in picking out the cutest babies

Everyone oohs and ahs over babies. Ironically, new research suggests that young women taking oral contraceptives are especially good at picking out babies with the most adorable little mugs.

YOU GOTTA SEE THE BABY Women who are premenopausal or are taking contraceptives exhibited special skill at detecting the cuteness of babies such as this one, a 6-month-old shown in modified images that added (left) or subtracted (right) cuteness from the child’s actual face. Sprengelmeyer

AVERAGED APPEAL In a new study, researchers first used sets of babies’ faces to create averaged cute male (top left) and female (bottom left) faces, as well as averaged less cute male (top right) and female (bottom right) faces. Sprengelmeyer

Female sex hormones sensitize women to differences in babies’ cuteness, propose psychologist Reiner Sprengelmeyer of the University of St. Andrews in Scotland and his colleagues. When given choices between computer-manipulated images of a baby’s face, premenopausal women discern gradations in the cuteness of the face better than either postmenopausal women or men of all ages, Sprengelmeyer’s group reports in the February Psychological Science.

In the new study, young women taking hormone-boosting contraceptive pills outdid those not taking contraceptives, as well as premenopausal women in general, at detecting babies’ cuteness.

Women of all ages identified subtle size differences between pairs of squares with comparable skill, indicating that hormone levels had no effects on basic visual faculties, the researchers assert. Instead, relatively high reproductive hormone levels in premenopausal women make them more emotionally responsive to cute babies, the team suggests.

“Cuteness is one of the factors that determine how strongly a mother interacts with her infant,” Sprengelmeyer says. A 1995 investigation found that mothers of babies independently rated as more attractive were particularly affectionate and playful with their children, whereas mothers of less-attractive babies provided routine care without much overt affection. 

A hormone-linked sensitivity to facial cuteness may prompt mothers to bond emotionally with their babies, Sprengelmeyer speculates.

“It’s tough to know what to make of these findings without knowing the ways in which cute babies differ from uncute babies,” remarks psychologist Steven Gangestad of the University of New Mexico in Albuquerque. It’s not known whether a cute face signals a baby’s physical vigor or other advantageous characteristics to a mother, Gangestad notes, or whether mothers who invest special effort in raising cute babies reap big dividends later.

Sprengelmeyer’s team asked independent raters to classify a series of babies’ faces on a 7-point scale. Then the researchers picked 40 faces, half boys and half girls, that the independent raters had agreed were cute or less cute. Using a computer program that incorporated data from 174 facial landmarks, the team defined the average shape of cute and less cute faces. Those average faces provided baseline data so the researchers could create faces with varying cuteness from five new male and five new female babies’ faces.

Adult volunteers viewed pairs of faces of the same baby and tried to identify the cuter face. On some trials, faces differed greatly in cuteness. On others, cuteness differed slightly.

An initial experiment included 24 young women and 24 young men, ages 19 to 26, as well as 24 older women and 11 older men, ages 45 to 60. A second experiment consisted of 10 premenopausal and 10 postmenopausal women, none of whom took hormone replacement therapy or had undergone a hysterectomy. A final experiment involved 24 young women, half of whom took oral contraceptives.

Sprengelmeyer’s group plans to examine whether sensitivity to babies’ cuteness rises and falls in concert with changing progesterone and estrogen levels during women’s menstrual cycles.

Bruce Bower has written about the behavioral sciences for Science News since 1984. He writes about psychology, anthropology, archaeology and mental health issues.