Research from the University of Lethbridge has suggested that high stress levels during pregnancy might lead to premature births in future generations. This could help explain the high number of premature births that some regions have. The study is not suggesting that the stress to premature pregnancy effect is immediate, but rather that it means the daughters of stressed women will have a higher risk of a shortened pregnancy.
The hypothesis has been drawn up after researchers observed the birthing behavior of rats. When the rats were put in stressful situations during the late stages of pregnancy, they gave birth at the normal time. However, the offspring of the stressed rats had shorter pregnancies and therefore a higher number of their own babies were born before what would be considered a normal gestation period was up.
According to the World Health Organization (WHO) up to 15 million babies are born prematurely every year. This is approximately one in every 10. Scientists have seen that chemical exposure may influence this, but are now beginning to understand that stress also plays a large role.
Gerlinde Metz, professor of neuroscience, explains that once the “footprint” of stress can be better understood, the risk of pre-term birth can be accessed in future generations. This allows for prediction of shorter pregnancies and intervention should it be required in order to keep mother and baby safe.
According to Metz, stress can alter genes. Stressed out pregnant ladies can pass on these altered genes to their daughters. This is why in the rat experiments it was the daughters of the stressed mother rats who showed shorter pregnancies. The research suggests that the same could be true in humans, and this might explain why in some areas of the world, more pre-term births are seen than others