‘Special occasion drinking’ during pregnancy could cause insulin resistance, which increases the likelihood of diabetes, in male offspring, suggests a new study conducted in rats.
“Even a small amount of alcohol during pregnancy can be harmful, so if you’re planning on getting pregnant don’t drink,” said senior author Dr. Lisa Akison, a researcher in the School of Biomedical Sciences and the Child Health Research Centre at the University of Queensland.
“Families, partners and friends should support a woman’s choice not to drink alcohol during pregnancy.”
“If a woman accidentally becomes pregnant, and unknowingly drinks alcohol during the first part of their pregnancy, the important thing once they know is to stop drinking, have a good diet and take care of themselves throughout the remainder of the pregnancy.”
In the study, the team mimicked ‘special occasion drinking,’ such as a family barbeque or birthday party, where a pregnant mother might be encouraged to have one or two alcoholic drinks.
Male rats exposed to this low level of prenatal alcohol showed signs of becoming diabetic at around six months old.
The scientists only gave alcohol to the mother rats on two days during their pregnancy.
The rats’ blood alcohol concentration only reached 0.05%, and yet their male offspring became almost diabetic, with insulin levels reaching higher than expected to maintain normal blood sugar levels.
Another interesting finding was that insulin resistance was sex-specific, occurring only in the male rats.
There are a couple of potential reasons for this, one being that during pregnancy, the placenta adapts to a prenatal stress differently depending on if it’s a male or female fetus, and this can impact on fetal growth and development.
The other factor is hormone changes as offspring grow into adulthood.
In this case, estrogen protects against insulin resistance, and because males don’t have high estrogen, they don’t experience the same protection.
“While the research is in its early stages, it raises questions about the safety of alcohol during pregnancy,” Dr. Akison said.
“More research is needed to establish any definitive link between alcohol and insulin resistance in humans.”
“Our results highlight that alcohol consumption during pregnancy has the potential to affect the long-term health of offspring,” the authors said.
The findings were published in the Journal of Physiology.
Tam M.T. Nguyen et al. Prenatal alcohol exposure programs offspring disease: Insulin resistance in adult males in a rat model of acute exposure. Journal of Physiology, published online October 8, 2019; doi: 10.1113/JP278531