Table 2. Incidence rates of epilepsy (per 100 000 person-years) and adjusted incidence rate ratios overall and according to type of prenatal antibiotic exposure within 30 days before conception or during pregnancy.

Antibiotic use	Births, N	Epilepsy cases, N	Person-years	Incidence rate	Adjusted* incidence rate ratio (95% CI)
None	131 307	587	730 657	8·0	1·0
Any	60 076	361	311 176	11·6	1·40 (1·22–1·61)
Pivmecillinam	17 756	106	76 527	13·9	1·55 (1·25–1·93)
Penicillin V	27 150	177	145 012	12·2	1·56 (1·30–1·87)
Other penicillins	12 259	79	65 755	12·0	1·46 (1·15–1·87)
Sulfonamides/trimethoprim	12 748	83	67 782	12·2	1·42 (1·12–1·82)
Macrolides	5 847	46	33 697	13·7	1·61 (1·15–2·25)

*Adjusted for birth year, birth order (1, 2+), maternal age (≤20, 21–34, ≥35), smoking in pregnancy (yes/no), maternal history of epilepsy, and maternal history of diabetes or preeclampsia/eclampsia.