. Author manuscript; available in PMC: 2014 Jul 1.

Published in final edited form as: Paediatr Perinat Epidemiol. 2013 Jun 3;27(4):340–345. doi: 10.1111/ppe.12064

Table 2.

Multivariable logistic regression modeling of antiherpetic medication use on the risk of gastroschisis by pregnancy exposure window among participants of National Birth Defects Prevention Study, 1997-2007


		Gastroschisis cases		Controls		Unadjusted		Adjusted^a
Genital Herpes Antiherpetic use exposure window^b		n	%	n	%	OR	95% CI	OR	95% CI

All	All	941	100.0	8339	100.0
No	No antiherpetic use	911	96.8	8213	98.5	Reference
No	Antiherpetic use during early pregnancy	4	0.4	10	0.1	3.61	[1.13, 11.53]	4.68	[1.15, 19.03]
No	Antiherpetic use exclusively outside of early pregnancy	4	0.4	18	0.2	2.00	[0.68, 5.93]	2.69	[0.81, 8.93]
Yes	No antiherpetic use	16	1.7	55	0.7	2.62	[1.50, 4.60]	3.00	[1.58, 5.68]
Yes	Antiherpetic use during early pregnancy	6	0.6	17	0.2	3.18	[1.25, 8.10]	4.68	[1.65, 13.28]
Yes	Antiherpetic use exclusively outside of early pregnancy	0	0.0	26	0.3	Not modeled		Not modeled

The covariates for adjusted models included maternal age at delivery (13-19, 20-24, 25-29 [reference], 30-50 years) and BMI before conception (<18.5, 18.5-25 [reference], >25, missing)

Early pregnancy was defined as the month before conception through the third month of pregnancy.