Can a Mother's Autoimmune Disease During Pregnancy Affect a Child's Type 1 Diabetes Risk?

Type 1 diabetes is an autoimmune condition—meaning the immune system mistakenly attacks the insulin-producing cells in the pancreas. Scientists have long known that genetics play a role in Type 1 diabetes risk, but they also suspect that things happening during pregnancy might influence whether a child develops autoimmune diseases later in life.

When a mother has an autoimmune disease during pregnancy, researchers wondered whether this could somehow affect her child's future immune development and Type 1 diabetes risk. At the same time, it wasn't clear how much of any connection would be due to prenatal factors versus simply inheriting the same genetic predisposition from the family.

This was a population-based cohort study using Swedish national health registers—meaning researchers tracked real medical records for entire groups of children over time rather than conducting an experiment. They included every child born in Sweden between 2001 and 2014 and followed them from birth until they either developed Type 1 diabetes, moved away, died, or the study ended on December 31, 2023.

The study compared children whose mothers had autoimmune diseases during pregnancy to those whose mothers did not. Researchers also looked at whether fathers' autoimmune diseases before childbirth were connected to offspring Type 1 diabetes risk. To help separate genetics from pregnancy effects, they performed 'cousin analyses'—comparing cousins who share family genes but whose mothers may have different autoimmune disease histories.

The study included 1,455,645 children (about 51% male and 49% female) with a median age of 15.3 years at the end of follow-up. During the average of 15.3 years tracked, 10,273 children (0.71%) developed Type 1 diabetes.

The research examined associations between a broad spectrum of maternal autoimmune diseases during pregnancy and Type 1 diabetes in offspring, and directly compared these associations to paternal autoimmune diseases. The cousin analyses helped the researchers understand how much of any observed association might be explained by shared family genetics rather than pregnancy-related factors.

This large, rigorous study adds to our understanding of how multiple factors—both genetic and prenatal—may influence Type 1 diabetes risk. By comparing maternal and paternal contributions and using cousin analyses, researchers can better tease apart the separate roles of pregnancy environment versus inherited genetic risk.

For families concerned about Type 1 diabetes, this research highlights that the condition's roots are complex. While this study provides important data, it is one piece of a larger puzzle. If you have questions about your own family's Type 1 diabetes risk or family health history, speak with your healthcare provider or a genetic counselor.

Source: JAMA pediatrics. Evidence type: PubMed indexed literature. Type1Cure is an information and intelligence hub, not a medical advice service. This article summarizes published research and does not provide diagnosis, treatment, or personal medical guidance. Always talk to your own care team before changing anything about your Type 1 diabetes management.