Featured Research

from universities, journals, and other organizations

Study Suggests That Tomboys May Be Born, Not Made

Date:
November 12, 2002
Source:
Center For The Advancement Of Health
Summary:
Levels of testosterone during pregnancy appear to influence the gender-role behavior of preschool girls, according to a new study.

Levels of testosterone during pregnancy appear to influence the gender-role behavior of preschool girls, according to a new study.

Related Articles


Researchers measured pregnant women's levels of testosterone, then evaluated the behavior of their children at age 3 1/2. The greater the maternal testosterone level, the more likely girls were to engage in "masculine-typical" gender-role behavior, such as playing with toys typically preferred by boys. No correlation was found for boys' behavior, however.

The researchers based their hypotheses on animal studies that have shown a correlation between maternal levels of testosterone and behavior in female offspring.

"Because hormones influence basic processes of brain development, they also exert permanent influences on behavior," says lead author Melissa Hines, Ph.D., of City University in London "In both rats and rhesus monkeys, genetic female animals treated with testosterone during critical periods of prenatal or early postnatal life show increased levels of … male-typical play behavior as juveniles."

Hines and her co-authors note that girls with congenital adrenal hyperplasia (CAH), a genetic disorder involving prenatal exposure to high levels of male hormones, tend to prefer masculine-typical toys and activities.

The study results appear in the November-December issue of Child Development.

Participants were part of the Avon Longitudinal Study of Parents and Children, a long-term study of biological, environmental and social factors associated with pregnancy outcomes and child health. A total of 13,998 pregnant women -- who represented 90 percent of all pregnancies occurring in the Avon, England, area during an 18-month period in the early 1990s -- enrolled in the study. Data from 679 offspring of the 14,138 children born during the study were analyzed.

The researchers obtained blood samples from the pregnant women during routine prenatal medical care; 55 percent of the women had blood taken between weeks 8 and 24 of the pregnancy; a quarter of the women had the samples taken between weeks 5 and 7, and the remainder after week 25. The samples were analyzed for levels of testosterone and a hormone that limits the ability of testosterone to act, called sex hormone binding globulin.

Once each child reached age 3 1/2, a primary caregiver completed the Pre-School Activities Inventory (PSAI), which assesses the child's engagement in various sex-typed behaviors, such as play with certain toys, games and activities. Higher scores indicate more masculine-typical behavior. The questionnaire was completed again when the child was 3 1/2.

The authors found a link between testosterone level in mothers and girls' scores on the PSAI, with high testosterone levels related to high "masculine" scores. No relationship was found between testosterone levels and boys' gender-role behavior, however.

The researchers note that "sex differences in childhood gender-role behavior, including toy, playmate and activity preferences, develop as a consequence of numerous influences. … For instance, parents, teachers and peers provide more positive reinforcement for sex-congruent play than for play that is not sex-congruent."

They therefore identified background variables from the data that may be linked to gender-role behavior, such as maternal education, the presence of older brothers or sisters in the home, the presence of a male adult living in the home, and parental adherence to traditional sex roles.

"These background variables cannot account for the observed relation between testosterone and PSAI scores in pre-school age girls," writes Hines.

The authors suggest that the effects were not seen in boys because boys ordinarily are exposed to higher levels of prenatal testosterone.

"Compared to girls, boys are more strongly encouraged to behave in sex-typical ways and are more strongly discouraged from engaging in cross-gendered behavior," they write. "Thus, girls may be more likely than boys to manifest hormone-related predispositions to gender-role behaviors more characteristic of the other sex, because these predispositions are less likely to be counteracted by other influences."

The study was supported by the Wellcome Trust. The Medical Research Council, Department of Health, the Department of the Environment, British Gas and other companies also support the Avon Longitudinal Study of Parents and Children. The U.S. Public Health Service (HD 24542) also supports Dr. Hines' research.


Story Source:

The above story is based on materials provided by Center For The Advancement Of Health. Note: Materials may be edited for content and length.


Cite This Page:

Center For The Advancement Of Health. "Study Suggests That Tomboys May Be Born, Not Made." ScienceDaily. ScienceDaily, 12 November 2002. <www.sciencedaily.com/releases/2002/11/021112075626.htm>.
Center For The Advancement Of Health. (2002, November 12). Study Suggests That Tomboys May Be Born, Not Made. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2002/11/021112075626.htm
Center For The Advancement Of Health. "Study Suggests That Tomboys May Be Born, Not Made." ScienceDaily. www.sciencedaily.com/releases/2002/11/021112075626.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Mind & Brain News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Prenatal Exposure To Pollution Might Increase Autism Risk

Prenatal Exposure To Pollution Might Increase Autism Risk

Newsy (Dec. 18, 2014) Harvard researchers found children whose mothers were exposed to high pollution levels in the third trimester were twice as likely to develop autism. Video provided by Newsy
Powered by NewsLook.com
Yoga Could Be As Beneficial For The Heart As Walking, Biking

Yoga Could Be As Beneficial For The Heart As Walking, Biking

Newsy (Dec. 17, 2014) Yoga can help your weight, blood pressure, cholesterol and heart just as much as biking and walking does, a new study suggests. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins