Obesity and cardiometabolic risk factors during pregnancy

PURPOSE:

To assess cardiometabolic risk factors during normal pregnancy and the influence of maternal obesity on them.

METHODS:

This study included 25 healthy pregnant women with a single pregnancy and a gestational age of less than twenty weeks. Longitudinal analysis of blood pressure, body weight, body mass index (BMI), serum concentrations of leptin, adiponectin, cortisol, total cholesterol and fractions, triglycerides, uric acid, fasting glucose, oral glucose tolerance test, HOMA-IR and insulin/glucose ratio was performed each trimester during pregnancy. In order to evaluate the impact of obesity, pregnant women were divided into two groups based on BMI for the first quarter of pregnancy: Gpn for pregnant women with BMI<25 kg/m² and Gso for BMI≥25 kg/m². One-Way ANOVA for repeated measurements or Friedman test and Student-t or Mann-Whitney tests for statistical comparisons and Pearson correlations test were used for statistical analysis.

RESULTS:

The mean values for the first quarter of pregnancy for the following parameters were: age: 22 years; weight: 66.3 kg and BMI 26.4 kg/m², with 20.2 and 30.7 kg/m² for the Gpn and Gso groups, respectively. Mean weight gain during pregnancy was ±12.7 kg with 10.3 kg for the Gso group and 15.2 kg for the Gpn group. Regarding plasma determinations, cortisol, uric acid and lipid profile increased during all trimesters of pregnancy, except for HDL-cholesterol, which did not change. Blood pressure, insulin and HOMA-IR only increased in the third quarter of pregnancy. The Gso group tended to gain more weight and to show higher concentrations of leptin, total cholesterol, LDL-cholesterol, VLDL-cholesterol, TG, glucose, insulin, HOMA-IR, besides lower HDL-cholesterol and greater diastolic blood pressure in the 3^rdquarter of pregnancy. Three pregnant women developed gestational hypertension, presented prepregnancy obesity, excessive weight gain, hyperleptinemia and an insulin/glucose ratio greater than two. Weight and BMI were positively correlated with total cholesterol and its LDL fraction, TG, uric acid, fasting blood glucose, insulin and HOMA-IR; and were negatively correlated with adiponectin and HDL-cholesterol. Leptin level was positively correlated with blood pressure.

CONCLUSIONS:

The metabolic changes in pregnancy are more significant in obese women, suggesting, as expected, an increased risk of cardiometabolic complications. During their first visit for prenatal care, obese women should be informed about these risks, have their BMI and insulin/glucose ratio calculated along with their lipid profile to identify pregnant women at higher risk for cardiovascular diseases.

Pregnancy; Obesity; Leptin; Adiponectin; Hypertension; Risk factors