Animal Study Links Stress to Infertility

Researchers in China have demonstrated a link between stress and fertility issues in mice that could hold true for humans as well.

The small animal study found that female rats exposed to stress-inducing scream sounds ended up with a diminished ovarian reserve, which is defined as reproductive potential based on the number and quality of eggs.

The researchers exposed female rats to a scream sound for 3 weeks and analyzed the effect on their sex hormones, the number and quality of their eggs, and their ability to get pregnant and have babies after mating.

They found the scream sound decreased the rats’ estrogen, which is a group of hormones that play an important role in growth and reproductive development. The rats also presented with lower levels of Anti-Mullerian hormone, which is made by the ovaries and helps form reproductive organs. The scream sound also lowered the number and quality of the women's eggs and resulted in smaller litters.

Scream sound stress also induced primordial and preantral follicles loss and augmented granulosa cell apoptosis in ovarian growing follicles. “Based on these results we suggest that chronic [psychological stress-] induced loss of ovarian reserve by accelerated primordial follicle activation and destruction of growing follicles, which results in follicle depletion and decreased fertility,” according to the paper’s abstract.

“Based on these findings, we suggest stress may be associated with diminished ovarian reserve,” says coauthor Wenyan Xi, Ph.D., of the Second Affiliation Hospital of Xi’an Jiao Tong University in Xian, China. “It is important to determine an association between chronic stress and ovarian reserve because doing so may expand our appreciation of the limitations of current clinical interventions and provide valuable insight into the cause of diminished ovarian reserve.”

The study, entitled “Scream Sound Induced Chronic Psychological Stress Results in Diminished Ovarian Reserve in Adult Female Rat,” was published recently in the journal Endocrinology. The work received funding from the Natural Science Foundation of Shaanxi Provincial Department of Education.