Fertility Treatment and Childhood Epilepsy: A Nationwide Cohort Study.

BACKGROUND

Fertility treatment includes hormonal stimulation of the woman and in vitro manipulation of gametes and embryos that may influence prenatal brain development. We aimed to investigate the association between fertility treatment and childhood epilepsy, including specific types of treatment and indications, as well as subtypes of epilepsy.

METHODS

In this nationwide birth cohort study, we included all pregnancies in Denmark resulting in live-born singletons, 1995-2003. Children conceived by fertility treatment and children developing epilepsy (until 2013) were identified from Danish national registers.

RESULTS

A total of 565,116 pregnancies were included; 8,071 children (1.4%) developed epilepsy. Children conceived after ovulation induction or intrauterine insemination had a slightly higher risk of childhood epilepsy (hazard ratio [HR]: 1.15; 95% confidence interval [CI]: 1.00, 1.31). The association was more pronounced for the subtypes idiopathic generalized and focal epilepsy. Regarding the specific hormonal treatments, only clomiphene citrate was associated with an increased risk of childhood epilepsy, also in a sibling analysis (HR: 2.07; 95% CI: 1.05, 4.08). In vitro fertilization or intracytoplasmic sperm injection was not associated with an overall increased risk of childhood epilepsy but with idiopathic generalized epilepsy (HR: 1.43; 95% CI: 0.99, 2.05). No clear associations were seen regarding other treatment types or indications.

CONCLUSIONS

Children conceived by ovulation induction or intrauterine insemination with clomiphene citrate may be at slightly increased risk of childhood epilepsy. Furthermore, children conceived by in vitro fertilization or intracytoplasmic sperm injection may be at slightly increased risk of idiopathic generalized epilepsy.