Placental Laterality as a Predictor for Development of Pre-Eclampsia

BACKGROUND Hypertensive disorders complicate 5 to 10 percent of all pregnancies; Pre-eclampsia syndrome, either alone or superimposed on chronic hypertension, is the most dangerous. 16% of maternal deaths were reported due to hypertensive disorders in developed countries according to WHO. The basic classification is of 4 types: Gestational hypertension, pre-eclampsia and eclampsia syndrome, chronic hypertension, pre-eclampsia superimposed on chronic hypertension. Gestational hypertension- blood pressure of >140/90 mmHg without proteinuria, developing after 20 weeks of gestation in a previously normotensive woman. Pre-eclampsia is a multisystem disorder of unknown aetiology is characterised by blood pressure of >140/90 mmHg with proteinuria after 20 weeks of gestation in a previously normotensive and nonproteinuric woman. Eclampsia is pre-eclampsia complicated with grand mal seizures and/or coma. Chronic hypertension is known hypertension before pregnancy or hypertension diagnosed first time before 20 weeks of pregnancy. METHODS This is a prospective observational study carried out in the department of obstetrics and gynaecology of Chalmeda Anand Rao Institute of Medical Sciences, Karimnagar. The study period was two years from January 2017 to March 2019. A total of 50 singleton pregnant women were included in the study to evaluate relationship between placental location and occurrence of pre-eclampsia and to find out whether placental laterality as determined by ultrasound can be used as a predictor of development of pre-eclampsia. To evaluate relationship between placental location and occurrence of pre-eclampsia, incidence of pre-eclampsia in patients with centrally and laterally located placenta was studied to find out as to whether placental laterality as determined by ultrasound can be used as a predictor of development of pre-eclampsia. RESULTS The incidence of pre-eclampsia was 14 in 50 singleton pregnancies. The maximum number of pre-eclampsia occurred between 21-25 years and was more common in primigravida (49%) than in second and multigravida. Out of 49% primigravida, 11% had lateral placenta and 38% had central placenta. Out of 11% lateral placenta 7% developed severe pre-eclampsia. Incidence of complications of pre-eclampsia like IUGR and low APGAR score were also more when pre-eclampsia has developed with a laterally implanted placenta compared to central placenta. All these show evidence of existence of significant association between placental laterality and presence of pre-eclampsia, intra uterine growth restriction or both. CONCLUSIONS Ultrasonography is simple, non-invasive, easy to perform, cost effective, diagnostic method to identify high risk cases. Females with laterally located placenta have a five times greater risk of developing pre-eclampsia. So, these pregnancies may require careful obstetric management to achieve a more favourable outcome and decrease the maternal and perinatal morbidity associated with pre-eclampsia