Scientists and researchers all around the world are trying to find products that affect male fertility and examine conditions that cause male-factor infertility. Recently we covered some findings that suggest consuming too much fast food negatively affects male fertility, but the new study shows that the ground reasons might be hiding deeper inside – in the mom’s womb.
The researchers at the University of Western Australia examined reproductive hormones and sperm samples of 643 men at the age of 20. They also questioned their mothers about their life conditions and overall feelings during two points throughout the pregnancy, from week 14 to 18 and from week 30 to 34.
407 men, or 63% of all responders, had mothers who lived through at least one stressful life event early in pregnancy. The stressful event was not clearly defined, but included such events as the death of a close relative or friend, separation or divorce, marital problems, job loss, money problems, health problems or pregnancy complications, residential move or immigration. Mothers of 87 men had endured at least three stressful life experiences early in pregnancy.
Compared to men with mothers who had stress-free early pregnancies, men whose mothers experienced one or more stressful life experiences were more likely to have lower testosterone level, lower total sperm count, less mobile sperm.
The biological connection between exposure to stressful life events during early months of pregnancy and male infertility isn’t well understood. Dr. Roger Hart and his and colleagues note that the period from 8th to 14th week of pregnancy are a critical period for male reproductive development, and it’s possible stress exposure during this time might interrupt the normal development process.
The study wasn’t a controlled experiment designed to prove whether or how any stress mothers experienced during pregnancy might directly impact their sons’ reproductive health decades later. And the researchers didn’t track the men to see who went on to father children.
Another limitation of the study is that not all people respond the same way to the same stressors, and researchers lacked data on how women felt about certain experiences that the study team classified as stressful life experiences. Factors like socioeconomic status, maternal education, and lack of insurance could all impact how women cope with stressful experiences.
Still, the results add to the evidence suggesting that it’s important to manage stress during pregnancy, said Dr. Muhammad Imran Omar, a researcher at the University of Aberdeen in the U.K. who wasn’t involved in the study: “Stressful life events are associated with a high level of stress hormone cortisol in the body, and these high levels are also found in the amniotic fluid and can affect fetal development.”
Photo: Getty Images
Source: Human Reproduction Journal by Oxford University Press