Objective: The association between low birth weight and type 2 diabetes is well established. We studied whether preterm birth carries a similar risk.
Research design and methods: The Helsinki Birth Cohort includes 13,345 men and women born between 1934 and 1944. Of them, 12,813 had adequate data on length of gestation, which we linked with data on special reimbursement for diabetes medication.
Results: Of the subjects, 5.1% had received special reimbursement after age 40. In subjects born before 35 weeks of gestation, the odds ratio for diabetes was 1.68 (95% CI 1.06-2.65) compared with that in those born at term. After adjustment for birth weight relative to length of gestation, the odds ratio was 1.59 (1.00-2.52).
Conclusions: Preterm birth before 35 weeks of gestation is associated with an increased risk of type 2 diabetes in adult life. The risk is independent of that associated with slow fetal growth.