Table 1

Summary of caffeine-related odds ratios expressed as percentage increased risk of harm (95% CI) for diverse negative pregnancy outcomes reported in meta-analyses published since 1998

Authors	Year	Risk, % (95% CI)	Consumption, mg/day*
		Miscarriage
Ferandes et al 56	1998	36 (1.29 to 1.45)	<150 vs ≥150
Greenwood et al 57	2014	14 (1.10 to 1.19)	Per 100
Li et al 58	2015	32 (1.24 to 1.40)	<150 vs ≥150
Chen et al 59	2016	7 (1.03 to 1.12)	Per 100
		Stillbirth
Greenwood et al 57	2014	19 (1.05 to 1.35)	Per 100
Chen et al 59	2016	9 (1.02 to 1.16)	Per 100
		Low birth weight/Small for gestational age
Ferandes et al 56	1998	51 (1.39 to 1.63)	<150 vs ≥150
Santos et al 80	1998	29 (1.18 to 1.41)/24 (1.05 to 1.43)	None/low vs high
Chen et al ⁸¹	2014	13 (1.06 to 1.21)	Per 100
Greenwood et al 57	2014	7 (1.01 to 1.12)/10 (1.06 to 1.14)	Per 100
Rhee et al 82	2015	38 (1.10 to 1.73)	Lowest vs highest
		Preterm birth
Santos et al 80	1998	Indeterminate	None/low vs high
Maslova et al 84	2010	No 'important' association	Lowest vs highest
Greenwood et al 57	2014	2 (−1.02 to 1.06)	Per 100
		Childhood acute leukaemia
Milne et al 89	2011	67 (1.20 to 2.32)	None vs 3+ cups coffee
Cheng et al 92	2014	72 (1.32 to 2.16)	None/low vs highest
Thomopoulos et al 93	2015	57 (1.16 to 2.11)	Lowest vs highest

*Level of maternal caffeine consumption (mg/day when given) used as the basis for estimating risk of harm.
CI, confidence interval.