Clustering of metabolic risk factors and adverse pregnancy outcomes: a prospective cohort study

Background The relative contributions of a cluster of metabolic risk factors to pregnancy complications are not fully understood. We investigated the correlation between clustering of metabolic risk factors and adverse pregnancy outcomes. Methods This prospective cohort study was performed on pregnant women who sought health care during their whole gestation in a women's and children's hospital. The pregnancy outcomes were also followed. Pre-pregnancy overweight/obesity, as well as pregnancy high triglycerides, low high-density lipoprotein-cholesterol, hyperglycemia and raised blood pressure were defined as metabolic risk factors. Adverse pregnancy outcomes included preterm delivery, small/large for gestational age, preeclampsia, gestational diabetes mellitus, neonatal asphyxia and foetal demise. Stratified analyses were conducted on a total of 5535 women according to classification in each metabolic risk factor. The adjusted odds ratio (OR) for adverse pregnancy outcomes according to the number of clustering metabolic factors was calculated using the logistic regression analysis. Results The number of metabolic risk factors and adverse pregnancy outcomes were positively correlated (P-trend < 0.001). Compared with women without a metabolic risk factor, women with one metabolic risk factor had a risk (OR = 1.67 95% CI 1.42-1.96) of adverse pregnancy outcomes. Women with a cluster of two metabolic risk factors tended to develop more adverse pregnancy outcomes (OR = 3.32 95% CI 2.69-4.10), and the risk was much higher in women with a cluster of three or more metabolic risk factors (OR = 10.40 95% CI 7.37-14.69). Conclusions Pregnant women with a cluster of metabolic risk factors are more likely to have adverse pregnancy outcomes. Copyright (C) 2016 John Wiley & Sons, Ltd.