Table 5.

Maternal Caffeine Consumption and Risk of Selected LDs Overall and Cross-Classified by Smoking Status, the NBDPS 1997 to 2007

	Isolated LDs				Isolated transverse				MCA LDs
Total caffeine (mg/day)	Cases	Controls	aORa,b	95% CI	Cases	Controls	aORb	95% CI	Cases	Controls	aORc	95% CI
All subjects
0–<10	79	1440		1.0	53	1440		1.0	40	1429		1.0
10–<100	228	2877	1.5	(1.2–2.0)	155	2877	1.5	(1.1–2.1)	93	2857	1.2	(0.8–1.7)
100–<200	167	1850	1.7	(1.3–2.3)	113	1850	1.8	(1.3–2.5)	44	1832	0.9	(0.6–1.4)
200–<300	81	1023	1.5	(1.1–2.1)	53	1023	1.5	(1.0–2.2)	26	1015	1.0	(0.6–1.7)
300+	64	879	1.4	(1.0–2.0)	39	879	1.3	(0.9–2.0)	20	873	0.9	(0.5–1.6)
Nonsmokers
0–<10	71	1363		1.0	47	1363		1.0	35	1353		1.0
10–<100	194	2501	1.6	(1.2–2.1)	133	2501	1.6	(1.1–2.3)	81	2486	1.3	(0.9–1.9)
100–<200	135	1502	1.8	(1.4–2.5)	90	1502	1.9	(1.3–2.7)	39	1487	1.1	(0.7–1.7)
200–<300	56	742	1.5	(1.1–2.2)	39	742	1.6	(1.0–2.5)	16	738	0.9	(0.5–1.7)
300+	34	470	1.5	(1.0–2.3)	20	470	1.3	(0.8–2.3)	9	467	0.9	(0.4–1.8)
Smokers
0–<10	8	77	2.1	(1.0–4.6)	6	77	2.5	(1.0–6.0)	5	76	2.9	(1.1–7.6)
10–<100	34	375	1.9	(1.2–2.9)	22	375	1.9	(1.1–3.2)	12	371	1.4	(0.7–2.8)
100–<200	32	346	2.0	(1.3–3.0)	23	346	2.2	(1.3–3.6)	5	345	0.6	(0.2–1.7)
200–<300	25	281	1.9	(1.2–3.0)	14	281	1.6	(0.9–3.0)	10	277	1.6	(0.8–3.4)
300+	30	407	1.6	(1.0–2.5)	19	407	1.6	(0.9–2.7)	11	405	1.2	(0.6–2.4)

^aaOR and associated 95% CIs.

^bORs adjusted for study site.

^cORs adjusted for education and any alcohol drinking during 1 month before pregnancy through the first trimester.

LD, limb deficiency; NBDPS, National Birth Defects Prevention Study; MCA, multiple congenital anomalies; aOR, adjusted odds ratio; CI, confidence interval.