The study, conducted by researchers at University Hospital Tubingen, could indicate that gestational diabetes has an impact on the infant’s brain. However, more research is needed to confirm this, because this study involved only a small number of participants.
The researchers analysed the data of 12 women with gestational diabetes and compared them to 28 participants with non-diabetic glucose tolerance. After giving 75g of glucose to the women, the researchers observed how their fetuses responded to sound.
60 minutes after consuming the glucose, the fetuses of the women with gestational diabetes were slower to respond to sound than those of the non-diabetic women.
“[This] study provides evidence that fetal brain reaction is influenced by postprandial metabolism, and fetuses of diabetic mothers react more slowly to auditory stimulation of their brain than fetuses of health mothers,” wrote the authors.
“This might indicate that gestational diabetes directly affects fetal brain function, which could be interpreted as central nervous insulin resistance of the offspring.”
All of the women were between 27 and 36 weeks into their pregnancy. None of the pregnancies had complications, and each participant carried only a single baby.
“It may be assumed that if brain insulin resistance is already induced in the fetal human brain, this may have consequences for the glucose metabolism of the offspring in later life.
“We speculate that prolonged auditory evoke response latency in the postprandial state specifically reflects the ability of the fetal brain to regulate peripheral metabolism.”
The study’s small size was not its only limitation: the researchers also measured responses to sound in pregnancies that had lasted between 27 and 36 weeks, despite the recommended window for diagnosing gestational diabetes being between 24 and 28 weeks.
The study did not reveal whether the potential brain effects of gestational diabetes would be reversible, or if they would affect the babies as they grew older. If reversible, the researchers stressed the importance of specialised prevention programmes to address the problem.
The authors wrote: “In addition, we currently do not know whether the differing brain reaction pattern in fetuses has consequences on the adult phenotype and is reversible or not. These essential questions should be addressed in long-term studies to improve or construct individual prevention programs.”
The findings were published in the Journal of Clinical Endocrinology &Metabolism.