Fertility treatment and childhood type 1 diabetes mellitus: a nationwide cohort study of 565,116 live births.

OBJECTIVE

To investigate the association between specific types of fertility treatment and childhood type 1 diabetes mellitus.

DESIGN

Nationwide birth cohort study.

SETTING

Not applicable.

PATIENT(S): All pregnancies resulting in a live-born singleton child in Denmark from 1995 to 2003.

INTERVENTION(S): Not applicable.

MAIN OUTCOME MEASURE(S): Childhood type 1 diabetes mellitus identified from redeemed prescriptions for insulin until 2013.

RESULT(S): The study included 565,116 singleton pregnancies. A total of 14,985 children were conceived by ovulation induction or intrauterine insemination, and 8,490 children were conceived by in vitro fertilization or intracytoplasmic sperm injection. During the follow-up period, 2,011 (0.4%) children developed type 1 diabetes mellitus. The primary analyses showed no association between fertility treatment and childhood type 1 diabetes mellitus. In secondary analyses, ovulation induction or intrauterine insemination with follicle-stimulating hormone was associated with an increased risk of type 1 diabetes mellitus (hazard ratio 3.22; 95% confidence interval 1.20 to 8.64). No clear associations were seen with other types of fertility treatment or with specific treatment indications.

CONCLUSION(S): No association between fertility treatment and childhood type 1 diabetes mellitus was found. Ovulation induction or intrauterine insemination with follicle-stimulating hormone may be associated with an increased risk of childhood type 1 diabetes mellitus. However, this finding may be due to chance or to confounding by indication and thus requires further investigation.