Subgroup analysis on women who had one or more pregnancy complications during the index pregnancy (i.e. preeclampsia, gestational hypertension, delivery of a small for gestational age infant, delivery of a preterm infant, and/or gestational diabetes mellitus) demonstrated that women who breastfed for at least six months had significantly lower maternal systolic and diastolic blood pressures, serum insulin and triglycerides, and higher HDL cholesterol. This evidence concerns the gene INS and gestational diabetes.