What is the Risk of Having Offspring with Cleft Lip/Palate in Pre-Maternal Obese/Overweight Women When Compared to Pre-Maternal Normal Weight Women? A Systematic Review and Meta-Analysis

OBJECTIVES The purpose of the study was to identify the risk of orofacial cleft in the offspring of women with pre-maternal obesity/overweight when compared with pre-maternal normal weight women. MATERIAL AND METHODS MEDLINE and EMBASE were searched from 1980 to July 2014 for cohort, case control and cross sectional studies. BMI were categorized according to WHO recommendation: normal weight (BMI 18.5 - 24.9), overweight (BMI 25 - 29.9) and obese (BMI ≥ 30). RESULTS Six studies were identified; three case control studies which were used for the meta-analysis and two cross sectional studies and one cohort study. Compared with women of recommended BMI, obese women were at increased odds of pregnancy affected by CLP (OR = 1.16; 95% CI 1, 1.34) and CP (OR = 1.14; 95% CI 0.95, 1.37). Overweight women were also at increased odds of pregnancy affected by CLP (OR = 1.06; 95% CI 0.93, 1.21) but not CP (OR = 0.89; 95% CI 0.75, 1.06). The results of the risk ratios reported in the cross sectional and cohort studies were similar to the results of the meta-analysis. CONCLUSIONS The results of this study reveal that there is an increased risk of having offspring with orofacial cleft in obese/overweight women. The reason for this association is not known. Although, the risk is small, it is important because of the increasing incidence of obesity.