Impact of Age at First Childbirth on Glucose Tolerance Status in Postmenopausal Women: The 2008–2011 Korean National Health and Nutrition Examination Survey

OBJECTIVE The objective of the current study was to determine whether there was an association between age at first childbirth and glucose tolerance status in postmenopausal women.

RESEARCH DESIGN AND METHODS This study was based on the data from the Korean National Health and Nutrition Examination Survey, conducted by the Korean Ministry of Health and Welfare from 2008–2011. Of 37,753 participants, data for 4,965 postmenopausal women were included in the analysis. Subjects were subdivided according to the age at first childbirth as follows: ≤19, 20–24, 25–29, and ≥30 years. Multivariate logistic regression analyses were used to identify whether there was an independent association between age at first childbirth and glucose tolerance status by adjusting for potential confounding factors.

RESULTS The prevalence of impaired fasting glucose (IFG) and diabetes was 21.8% (1.066 of 4.965) and 15.3% (774 of 4,965), respectively. Diabetes prevalence differed significantly between the subgroups and was higher with earlier age at first childbirth: it was 10.9% in subjects aged ≥30 years and 23.8% in subjects aged ≤19 years at first childbirth. After fully adjusting for potential confounding factors, including lifestyle, sociodemographic factors, known diabetes risk factors, and reproductive factors, age at first childbirth ≤19 years was significantly associated with diabetes (odds ratio 1.492 [95% CI 1.005–2.215]). No significant associations were found between age at first childbirth and IFG.

CONCLUSIONS Age at first childbirth influenced diabetes risk in postmenopausal women, and adolescent pregnancy was independently associated with a higher risk of diabetes in postmenopausal women.