Table 2.

Reported maternal fever, fever severity, and the use of antipyretic medication during the periconceptional period^* and risk for neural tube defects, Birth Defects Study, 1998–2015

Characteristic	NTD case (total = 375)	Control (total = 8247)	Crude OR (95% CI)	Adjusted OR† (95% CI)
	N (%)	N (%)
Maternal periconceptional fever reported
Yes	19 (5.1)	154 (1.9)	2.8 (1.7–4.6)	2.4 (1.5–4.0)
No	356 (94.9)	8093 (98.1)	1.0 (Reference)	1.0 (Reference)
Reported temperature of fever
≥101°F	6 (1.6)	62 (0.8)	2.2 (0.9–5.1)	2.1 (0.9–5.1)
<101°F	9 (2.4)	62 (0.8)	3.3 (1.6–6.7)	3.3 (1.6–6.9)
Not reported	4 (1.1)	30 (0.4)	–	–
Antipyretic treatment of reported fever
Yes	8 (2.1)	62 (0.8)	2.9 (1.4–6.2)	2.2 (1.0–4.9)
No	11 (2.9)	91 (1.1)	2.8 (1.5–5.2)	2.6(1.4–5.0)
Combination of reported temperature and use of antipyretic treatment for fever
≥101°F
Antipyretic treatment	2 (0.5)	27 (0.3)	1.7 (0.2–6.8)	1.4 (0.2–6.2)
No antipyretic treatment	4 (1.1)	34 (0.4)	2.7 (0.7–7.6)	2.9 (0.7–8.5)
< 101°F
Antipyretic treatment	3 (0.8)	26 (0.3)	2.6 (0.5–8.6)	2.2 (0.4–7.8)
No antipyretic treatment	6 (1.6)	36 (0.4)	3.8 (1.6–9.1)	4.2 (1.7–10.4)

^*Defined as the 28 days before to the 28 days after last menstrual period.

^†Adjusted for Study Center.