Babies born to women who are overweight, obese or diabetic during pregnancy have less mature lungs, according to studies in sheep.
Previous research has shown that overweight, obese or diabetic women during pregnancy have an increased risk of having a baby who experiences lung problems both at birth and later in infancy and childhood.
A team of researchers from the University of South Australia found that at-risk offspring had more under-formed lungs compared to offspring of normal weight mothers. The lungs produce a surfactant that serves two purposes: keeps the surfaces of the airways from sticking together, and fights bacteria and viruses. Immature lungs produce less surfactant, which means the lungs cannot perform their normal functions.
The researchers fed the pregnant sheep with a normal diet or a diet that provided 55% more energy, mimicking a pattern of overfeeding and obesity. Such nutrition was provided to animals during the last trimester of pregnancy, when the most critical stage of lung development occurs. Scientists observed the lungs of lambs before birth and one month after to assess lung growth and see if the number of cells that produce the surfactant was normal. They found that in the overnourished group, surfactant production was reduced, as was the number of cells producing it.
One month after birth, the amount of surfactant in infants is back to normal, so the long-term effects on lung maturation due to overweight, obesity, or maternal diabetes during pregnancy remains unclear.
The study authors recommend that overweight, obese, and diabetic pregnant women receive treatment to help their babies’ lungs mature before birth. It may also be helpful to consult a healthcare professional for overweight, obese and diabetic patients so that they can manage this condition before pregnancy, thereby reducing the risks of deteriorating the health of the unborn child.
In further studies, scientists will observe offspring throughout life to see if there is an increased risk of developing respiratory problems, such as bronchial asthma.