Many women struggle to conceive and give birth to a baby, a situation known to cause distress and anxiety. But maybe it works the other way around? Does stress cause infertility? Research over the past 20 years has attempted to determine whether levels of stress are associated with pregnancy rates, but the findings have been conflicting.
Now, in a study published today by The Endocrine Society, scientists tested whether female rats exposed to a distressing scream had reduced fertility or reduced ovarian reserve.
Ovarian reserve refers to the number and quality of ova (egg cells) remaining in a female mammal’s ovaries, and is therefore a measure of potential reproductive success in the future. Female mammals are born with a finite number of eggs in their ovaries, and they cannot generate more during their lifetime. Reduced ovarian reserve is the loss of normal reproductive potential in the ovaries due to a lower number or quality of the remaining eggs.
The researchers exposed a small sample of female rats to a screaming sound for a period of 3 weeks and then measured the effect of this stressor on the levels of sex hormones, the number and quality of remaining eggs, and the ability to conceive and to give, analyze. giving birth to young after mating.
“We investigated the effect of stress on ovarian reserve using a scream-sound model in rats,” said Dr. Wenyan Xi said. “We found that female rats exposed to the scream had reduced ovarian reserve and reduced fertility.”
The researchers found that rats exposed to the stressful sound had decreased levels of estrogen and anti-Müllerian hormone. Estrogen hormones are important in growth and reproductive development, and anti-Müllerian hormone, produced by the ovaries, helps form the reproductive organs. These female rats also had ovaries in their ovaries that were less numerous and of a lower quality, resulting in smaller litters of offspring.
“Based on these findings, we suggest that stress may be associated with reduced ovarian reserve,” Dr. Xi said. “Determining a relationship between chronic stress and ovarian reserve is important because it may increase our appreciation of the limitations of current clinical interventions and provide valuable insight into the cause of reduced ovarian reserve.”
The study is published in the journal Endocrinology.
By Alison Bosman, Earth.com Staff Writer