Stress could determine gender: research

Stressed expectant mothers could be making psychological changes to their daughters that will influence future genders, researchers say.

Researchers say pregnancy stress could cause an increase in male babies in future generations. (AAP)

Pregnancy stress can cause an increased likelihood of male babies in future generations, new research out of Tasmania has found.

Physiological changes caused by maternal stress can influence whether female offspring go on to give birth to more males or females, University of Tasmania researcher Amy Edwards said after conducting a series of tests using mice.

"This could be quite important for management and breeding programs - as well as the livestock industry - which often have trouble with vastly differing ratios of male and female offspring," Dr Edwards said on Thursday.