Media Releases

Psychologists find link between ovulation and women’s ability to identify heterosexual men

June 22, 2011

TORONTO, ON – A new study by psy­chol­o­gists at the Uni­ver­si­ty of Toron­to and Tufts Uni­ver­si­ty shows that a woman can more accu­rate­ly iden­ti­fy a man’s sex­u­al ori­en­ta­tion when look­ing at his face when she is clos­est to her time of peak ovu­la­tion. Fur­ther, hav­ing roman­tic thoughts or a mat­ing goal height­ens a wom­an’s abil­i­ty to dis­crim­i­nate between straight and gay men.

“This effect is not appar­ent when a woman is judg­ing anoth­er female’s ori­en­ta­tion,” says Pro­fes­sor Nicholas Rule of the Depart­ment of Psy­chol­o­gy at the Uni­ver­si­ty of Toron­to, lead author of a new study pub­lished in Psy­cho­log­i­cal Sci­ence. “This sug­gests that fer­til­i­ty influ­ences a het­ero­sex­u­al woman’s atten­tion to poten­tial mates rather than mere­ly increas­ing sen­si­tiv­i­ty to sex­u­al ori­en­ta­tion or non­ver­bal cues more gen­er­al­ly.”

In the first of three exper­i­ments, 40 under­grad­u­ate women judged the sex­u­al ori­en­ta­tion of 80 images of men’s faces. Forty of the pho­tos were of self-iden­ti­fied gay males while the oth­er 40 were of straight men. The men did not dif­fer in emo­tion­al expres­sion or attrac­tive­ness, and the female par­tic­i­pants were encour­aged to use their intu­ition in mak­ing judg­ments. In addi­tion, the women report­ed the length of time since their last men­stru­al cycle and its aver­age dura­tion; none were using any sys­temic con­tra­cep­tive med­ica­tions.

The researchers cor­re­lat­ed the par­tic­i­pants’ accu­ra­cy in judg­ing sex­u­al ori­en­ta­tion with the point at which the women were in their fer­til­i­ty cycle, and found that the near­er women were to peak ovu­la­tion, the more accu­rate they were at judg­ing each male’s sex­u­al ori­en­ta­tion.

The sec­ond exper­i­ment fea­tured 34 women who viewed a sim­i­lar series of female faces, 100 of whom were self-iden­ti­fied les­bians while anoth­er 100 were straight. The researchers found no rela­tion­ship between fer­til­i­ty and accu­rate judg­ments of the women’s sex­u­al ori­en­ta­tion.

“Togeth­er, these find­ings sug­gest that women’s accu­ra­cy may vary across the fer­til­i­ty cycle because men’s sex­u­al ori­en­ta­tion is rel­e­vant to con­cep­tion and thus of greater impor­tance as women are near­er to ovu­la­tion.”

The researchers test­ed this hypoth­e­sis fur­ther with a third exper­i­ment in which female par­tic­i­pants were primed with a mat­ing goal in order to manip­u­late repro­duc­tive rel­e­vance. Half of the 40 par­tic­i­pants were asked to read a sto­ry which described a roman­tic encounter while the oth­er half did not, before per­form­ing the same tasks in the two pre­vi­ous stud­ies. Rule and his col­leagues found that the women primed with a mat­ing goal were sig­nif­i­cant­ly more accu­rate in their judg­ments than the women who were not, imply­ing that induc­ing roman­tic or mat­ing-relat­ed thoughts improved accu­ra­cy in iden­ti­fy­ing men’s sex­u­al ori­en­ta­tions.

The find­ings are pre­sent­ed online in a paper titled “Mat­ing Inter­est Improves Wom­en’s Accu­ra­cy in Judg­ing Male Sex­u­al Ori­en­ta­tion” , pub­lished in Psy­cho­log­i­cal Sci­ence.



Nicholas Rule
Depart­ment of Psy­chol­o­gy
Uni­ver­si­ty of Toron­to

Sean Bet­tam
Com­mu­ni­ca­tions, Fac­ul­ty of Arts & Sci­ence
Uni­ver­si­ty of Toron­to

Jes­si­ca Lewis
Com­mu­ni­ca­tions, Fac­ul­ty of Arts & Sci­ence
Uni­ver­si­ty of Toron­to