Table 1. Incidence Rates and HRs of Epilepsy According to Maternal Diseases, Pregnancy Complications, and Neonatal Characteristics.

Characteristic	No. of Children	Epilepsy		HR (95% CI)
		No.	Rate per 10 000 Child-years	Unadjusteda	Adjustedb
Maternal Diseases and Pregnancy Complications
Maternal epilepsy
No	1 416 537	7494	6.72	1 [Reference]	1 [Reference]
Yes	5014	98	30.9	4.44 (3.62-5.45)	4.40 (3.56-5.43)
P value for trendc				<.001	<.001
Diabetic disease
No	1 401 240	7463	6.77	1 [Reference]	1 [Reference]
Gestational diabetes	13 999	85	8.28	1.21 (0.98-1.50)	1.25 (1.0-1.56)
Pregestational diabetes	6312	44	9.14	1.35 (1.0-1.81)	1.30 (0.94-1.78)
P value				.033	.04
Hypertensive disease
No	1 372 938	7272	6.74	1 [Reference]	1 [Reference]
Pregestational hypertension	8780	41	6.76	0.98 (0.72-1.33)	0.89 (0.64-1.23)
Preeclampsia	39 833	279	8.75	1.30 (1.16-1.47)	1.24 (1.09-1.41)
P value				<.001	.003
Chorioamnionitis
No	1 418 919	7559	6.78	1 [Reference]	1 [Reference]
Yes	2632	33	16.4	2.41 (1.71-3.40)	2.22 (1.53-3.21)
P value				<.001	<.001
Maternal infection
No	1 412 398	7526	6.78	1 [Reference]	1 [Reference]
Yes	9153	66	9.49	1.39 (1.10-1.78)	1.40 (1.09-1.80)
P value				.007	.009
Birth Characteristics and Neonatal Complications
Mode of delivery
Vaginal noninstrumental	1 090 372	5363	6.19	1 [Reference]	1 [Reference]
Vaginal instrumental	108 268	593	7.06	1.14 (1.04-1.24)	1.14 (1.04-1.25)
Elective cesarean section	107 501	776	9.79	1.56 (1.45-1.68)	1.51 (1.40-1.64)
Emergency cesarean section	108 699	785	9.65	1.54 (1.43-1.66)	1.53 (1.41-1.66)
Data missing	6711	75	11.06
P value for trendd				<.001	<.001
Newborn’s sex
Male	731 102	4062	7.07	1 [Reference]	1 [Reference]
Female	690 449	3530	6.50	0.92 (0.88-0.96)	0.91 (0.87-0.96)
P value				<.001	<.001
Gestational age at delivery, wk
Term (≥37)	1 348 059	6802	6.42	1 [Reference]	1 [Reference]
Moderately preterm (32-36)	59 434	530	11.31	1.76 (1.61-1.93)	1.69 (1.53-1.86)
Very preterm (28-31)	6025	107	22.94	3.56 (2.94-4.32)	3.50 (2.84-4.31)
Extremely preterm (22-27)	2484	65	37.16	5.72 (4.48-7.30)	5.51 (4.17-7.28)
Data missing	5549	88	16.52
P value for trend				<.001	<.001
Birth weight for gestational age (percentiles)
<3	22 482	322	18.3	2.86 (2.56-3.20)	2.75 (2.44-3.11)
3 to <10	66 773	460	8.92	1.39 (1.26-1.53)	1.30 (1.17-1.45)
10 to 90	1 150 500	5769	6.40	1 [Reference]	1 [Reference]
>90 to 97	123 167	621	6.25	0.98 (0.90-1.07)	0.99 (0.91-1.08)
>97	53 080	332	7.72	1.21 (1.08-1.35)	1.16 (1.03-1.30)
Data missing	5549	88	16.5
P value for trend				<.001	<.001
Birth trauma
No	1 395 887	7399	6.75	1 [Reference]	1 [Reference]
Yes	25 664	193	8.70	1.31 (1.13-1.51)	1.26 (1.09-1.47)
P value				<.001	.003
Any congenital malformation
No	1 337 941	5960	5.67	1 [Reference]	1 [Reference]
Yes	83 610	1623	24.8	4.38 (4.14-4.63)	4.28 (4.04-4.54)
P value				<.001	<.001
Chromosomal abnormalities
No	1 417 925	7269	6.52	1 [Reference]	1 [Reference]
Yes	3626	323	120.4	18.4 (16.4-20.6)	18.6 (16.5-20.9)
P value				<.001	<.001
Circulatory malformations
No	1 393 495	7133	6.50	1 [Reference]	1 [Reference]
Yes	28 056	459	22.2	3.38 (3.08-3.72)	3.29 (2.98-3.64)
P value				<.001	<.001
Nervous system malformations
No	1 418 642	6988	6.26	1 [Reference]	1 [Reference]
Yes	2909	604	300.4	47.7 (43.7-52.1)	46.4 (42.2-51.0)
P value				<.001	<.001
Meconium aspiration
No	1 419 773	7545	6.76	1 [Reference]	1 [Reference]
Yes	1778	47	34.10	5.04 (3.78-6.73)	4.51 (3.28-6.18)
P value				<.001	<.001
Hypoxic ischemic encephalopathy and related conditions
No	1 419 254	7329	6.57	1 [Reference]	1 [Reference]
Yes	2297	263	159.8	24.2 (21.3-27.5)	23.6 (20.6-27.1)
P value				<.001	<.001
Neonatal convulsions
No	1 418 805	7158	6.42	1 [Reference]	1 [Reference]
Yes	2746	434	227.4	35.2 (31.9-39.0)	33.5 (30.1-37.4)
P value				<.001	<.001
Birth asphyxia
No	1 407 317	7212	6.52	1 [Reference]	1 [Reference]
Yes	14 234	380	32.8	5.05 (4.56-5.61)	4.79 (4.28-5.36)
P value				<.001	<.001
Apgar score at 5 min
7-10	1 398 680	7062	6.42	1 [Reference]	1 [Reference]
4-6	10 521	257	32.7	5.06 (4.47-5.73)	4.91 (4.30-5.61)
0-3	2189	132	78.4	12.3 (10.3-14.6)	11.8 (9.79-14.2)
Data missing	10 161	141	16.1
P value for trend				<.001	<.001
Other Neonatal Complications
Neonatal infections
No	1 400 373	7276	6.62	1 [Reference]	1 [Reference]
Yes	21 178	316	17.8	2.72 (2.43-3.05)	2.60 (2.30-2.93)
P value				<.001	<.001
Neonatal hypoglycemia
No	1 383 582	7163	6.59	1 [Reference]	1 [Reference]
Yes	37 969	429	14.1	2.14 (1.94-2.36)	2.10 (1.90-2.33)
P value				<.001	<.001
Neonatal jaundice
No	1 362 345	7131	6.65	1 [Reference]	1 [Reference]
Yes	59 206	461	10.0	1.50 (1.37-1.65)	1.47 (1.33-1.63)
P value				<.001	<.001
Respiratory distress
No	13 77 310	7034	6.49	1 [Reference]	1 [Reference]
Yes	44 241	558	16.5	2.53 (2.32-2.76)	2.43 (2.21-2.66)
P value				<.001	<.001

Abbreviation: HR, hazard ratio.

^aFrom unadjusted Cox proportional hazards models. Robust estimates of the variance were calculated to account for women who delivered more than once during the study period.

^bFrom Cox proportional hazards models with robust estimates of variance. Covariates adjusted for maternal age, country of origin, educational level, cohabitation with a partner, parity, height, smoking during pregnancy, maternal epilepsy, and year of delivery.

^cWald χ² test.

^dWald test when a variable representing ordinal categories of BMI was introduced into the model as a continuous predictor.