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.