The study, which is bound to provoke controversy, showed that the women who were directly exposed to semen were less depressed. The researchers think this is because mood-altering hormones in semen are absorbed through the vagina. They say they have ruled out other explanations.
"I want to make it clear that we are not advocating that people abstain from using condoms," says Gordon Gallup, the psychologist at the State University of New York who led the team. "Clearly an unwanted pregnancy or a sexually transmitted disease would more than offset any advantageous psychological effects of semen."
His team divided 293 female students into groups depending on how often their partners wore condoms, and assessed their happiness using the Beck Depression Inventory, a standard questionnaire for assessing mood. People who score over 17 are considered moderately depressed.
The team found that women whose partners never used condoms scored 8 on average, those who sometimes used them scored 10.5, those who usually used them scored 15 and those who always used them scored 11.3. Women who weren't having sex at all scored 13.5.
What's more, the longer the interval since they last had sex, the more depressed the women who never or sometimes used condoms got. But the time since the last sexual encounter made no difference to the mood of women who usually or always used condoms.
The team also found that depressive symptoms and suicide attempts were more common among women who used condoms regularly compared with those who didn't. The results will appear in the journal Archives of Sexual Behavior.
And Gallup told New Scientist that his team already has unpublished data from a larger group of 700 women confirming these findings. In this study, the always-use-condoms group were more depres
Contact: Claire Bowles