Table 4.

Description of included studies

First author	Year of publication	Location	Type of study	Study period	Weight/height measurement	BMI classification	Adjusted for	Outcomes reported
Waller et al. [32]	2007	USA	Case control	Oct 1, 1997 to Dec 31, 2002	Retrospectively self-reported by the mother	UW < 18.5 NW ≥ 18.5 to < 25 OW ≥ 25 to < 30 Obese ≥ 30	Maternal race/ethnicity, maternal age, maternal educational level, parity, maternal smoking, folic acid intake	CP CLP
Stott-Miller et al. [46]	2010	Washington, USA	Case control	1987 to 2005	Birth certificate and drivers license records	UW < 18.5 NW ≥ 18.5 to < 25 OW ≥ 25 to < 30 Obese ≥ 30	Maternal education, maternal age, maternal smoking, maternal race, frequency matched for year of birth	CP CLP
Watkins et al. [58]	2003	Atlanta, USA	Case control	Jan 1992 to Aug 1997	Retrospectively self-reported by the mother	UW < 18.5 NW 18.5 to 24.9 OW 25 to 29.9 Obese ≥ 30	Maternal age, education, alcohol use, smoking, peri conceptional vitamin use, race	CL CP CLP
Block et al. [59]	2013	Florida, USA	Cross sectional	Mar 2004 to Dec 2009	From Birth certificate	UW < 18.5 NW 18.5 to 24.9 OW 25.0 to 29.9 Obese ≥ 30	Maternal race/ethnicity, maternal education, maternal smoking, maternal marital status, maternal nativity, maternal age	CP CLP
Marengo et al. [60]	2013	Texas, USA	Cross sectional	2005 to 2008	Birth/death certificates	UW < 18.5 NW 18.5 to 24.9 OW 25 to 29.9 Obese ≥ 30	Maternal age, maternal race/ethnicity	CP CLP
Rankin et al. [61]	2010	North of England, UK	Cohort study	Jan 2003 to Dec 2005	Hospital records	UW < 18.5 NW 18.5 to 24.9 OW 25 to 29.9 Obese ≥ 30	Maternal age, maternal ethnicity, pre-gestational diabetes, cigarette smoking status, index of multiple deprivation	CL CP CLP

NW = normal weight (reference weight); OW = overweight; UW = underweight; CL = cleft lip; CP = cleft palate; CLP = cleft lip with or without palate.