Placental morphology and the prediction of underlying cardiovascular risk factors
Pre-eclampsia (PE) is associated with an increased risk of future cardiovascular disease (CVD). It is characterized by new-onset hypertension and proteinuria, sometimes progressing into a multiorgan clinical manifestation. Maladaptive placentation or malperfusion, as well as predisposing cardiovascular or metabolic risk for endothelial dysfunction, contribute to the systemic inflammatory response that establishes the origins of the disease. The purpose of this study was to investigate the relationship between placental morphology and cardiovascular risk (CVR) when assessed at six months postpartum in women who experienced PE. Multivariable logistic regression was used to examine the relationship between placental morphology measures and calculated maternal lifetime risk of CVD at six months postpartum, with P<0.05 used to define significance. 186/216 women with PE who attended the Maternal Health Clinic met inclusion criteria. No significant differences were observed for placental morphometric measurements between women who screened as having a high vs. low lifetime risk profile for CVD at six months postpartum. However, using multivariable modelling that controlled for maternal age, pre-pregnancy BMI, gestational age at delivery, and severity of PE, a low placenta to birth weight ratio (<15%) was associated with an increased odds of high lifetime CVD risk (p<0.009). The findings of the current study identify clinical measurements that can be collected at the time of delivery which may help identify specific women who may benefit most from postpartum CVR screening and intervention. It was found that low placental to birthweight ratios, indicative of higher placental efficiency, were associated with an increased odds of high lifetime CVD risk in the mother when screened postpartum. Why underlying maternal CVR factors may lead to increases in placental efficiency are currently unclear, but certainly warrant further investigation and will be important to do a prospective validation study.