The Hidden Side of the Story between the Placenta and Preeclampsia: Preliminary Results of a Prospective Cohort of Pregnant Women in Cameroon

Introduction: Pre-eclampsia is a complication of pregnancy that generally occurs in the third trimester. It is associated with a maternal and foetal mortality rate of around 27%. In view of the grim picture painted by this condition for both mother and newborn, studies have been carried out into the early detection of patients at risk of developing pre-eclampsia. These make it possible to introduce pregnancy-specific monitoring and preventive strategies to reduce the incidence of the condition. Objective: To establish the link between placental ultrasound characteristics and the onset of pre-eclampsia. Methodology: A multicentre prospective cohort study was conducted in two hospitals in Yaoundé, namely the Yaoundé Gynaecological Obstetrics and Paediatrics Hospital and the Nkolndongo Health and Social Animation Centre, in the gynaecology and radiology departments over a period of 11 months, from October 2022 to August 2023. It included pregnant women who had undergone obstetric ultrasound between 12 and 18 weeks’ gestation. In addition to routine obstetric ultrasound, we performed obstetric Doppler measurements in these patients. The resistance index of the left and right uterine arteries, the umbilical artery and the placental volume were the characteristics sought. At the end of this examination, two groups were formed: cases (pathological Doppler group) and controls (normal Doppler group). Blood pressure and urine dipstick were taken at each antenatal visit until delivery, then during the immediate postpartum period and finally at 7 days, 21 days and 42 days after delivery. Results: Sixty-seven (67) patients were included. Of these, 35 (47.8%) had pathological Dopplers. Sixteen patients had arterial hypertension associated with proteinuria and were therefore labelled as pre-eclampsia (PE). This gives a prevalence of 23.9%. Fifteen (42.8%) of these patients belonged to the exposed group and one to the unexposed group. The mean IR of the pre-eclampsia patients was significantly higher than that of the patients without pre-eclampsia; respectively 0.74 ± 0.096 and 0.49 ± 0.097 for the right uterine arteries and 0.71 ± 0.13 and 0.52 ± 0.089 for the left uterine arteries. We found that an increase in the uterine artery resistance index was significantly associated with the onset of pre-eclampsia, with a relative risk of 13.7 and a p value < 0.001. The overall sensitivity, specificity and positive and negative