Comparative study of Placental Abnormalities in Normal and Specific High Risk Pregnancies by using Doppler, Histology and their Fetal Outcome

INTRODUCTION: Placenta is a vital lifeline between mother and fetus through which nutrients, oxygen, antibodies and hormones pass. Improper placentation and placental function could be potentially danger to the health of the mother and the fetus. High risk pregnancies are a small segment of the obstetric population, that produces the majority of maternal and infant mortality and morbidity. Upto 40% of high risk mothers experience placental damage. Placenta is one of the most remarkable organ in the sense that it has a very short life and yet very critical for continuation of the pregnancy and thus life of the baby in utero. For nine months it is effectively the lung, the gut and the kidney of the fetus. The term ‘Placenta’ is believed to have been introduced in 1559 by RAELDUS COLUMBUS who used this Latin work which actually means ‘Circular lake’. AIM OF THE STUDY: 1. To compare the placental abnormalities in normal and specific high risk pregnancies by using Doppler and Histology. 2. To study the possible, probable correlation with fetal outcome. MATERIALS AND METHODS: This study was carried out at the Institute of social obstetrics and Govt. Kasturba Gandhi Hospital, Triplicane, Chennai. Study Design: It is a prospective study of morphology and histology of placenta in randomly selected normal and specific high risk pregnancies and its correlation with fetal outcome. Period of Study: From May 2009 – October 2010. MATERIALS AND METHODS: 500 pregnant women between 21-35 yrs of age between gestational age of > 36 wks, coming to antenatal OP at KGH are selected. Each women is analysed in detail with 1) Age, 2) Parity, 3) Associated Medical / Obstetric Complication, 4) Gestational Age. They are classified into 2 groups. Group I - Normal cases (270), Group II - Specific High risk cases (230). Preeclampsia – 80, Gestational Diabetes Mellitus – 80, IUGR – 70. History, Physical Examination, Obstetrical Examination, Basic investigations, Hb% , urine analysis, blood grouping typing, pertaining to individual patients are carried out. They are offered the following test. Uterine Artery Doppler Ultrasonogram: Following are mainly looked; 1) Systolic Diastolic Ratio, 2) Early Diastolic Notch, 3) Pulsatility Index, 4) Resistance Index. They are followed till delivery once in 2 weeks and at the time of delivery, placenta is studied both grossly and histologically after formalin fixation. Fetal outcomes in these cases are observed. Inclusion Criteria: For Normal Pregnancies: • Primigravida between the age of 21-35 yrs, > 36 weeks of gestation. • With singleton gestation • No associated medical / obstetric complication. For specific high risk pregnancies: • Primigravida between the age of 21-35 years, > 36 weeks of gestation, with singleton gestation with the following high risk factors. • Preeclampsia, mild, and severe. • Gestational Diabetes Mellitus. • Intrauterine growth restriction. Exclusion Criteria: 1) Pregnant women 35 yrs. 2) Multiple pregnancy. 3) Anemia complicating pregnancy. 4) Placenta previa, Abruptio placenta. 5) HIV, HBSAg, Tuberculosis, syphilis complicating pregnancy. 6) Pregnant women other than primigravida. 7) Other known medical / obstetrical complication not mentioned in high risk Inclusion criteria. SUMMARY: This study is important by 3 factors; 1. Volume-500 cases of normal and high risk pregnancies. 2. Armamentarium – a tertiary hospital with hitech gadgets meeting all needs. 3. Variety – both morphological and histopathological study. Both positive and negative correlations are brought out. The positive correlations are for syncytial knot count, neutrophilic, infiltration, infarction, thickening of basement membrane, fibrinoid necrosis with fetal outcome. There is significant correlation between the presence of syncytial knot count with low APGAR and early neonatal death respectively, when the syncytial knot count is present in >60% of villi. There is significant correlation with infarction and low APGAR and early neonatal death.There is very significant correlation between fibrinoid necrosis and thickened basement membrane with low APGAR and early neonatal death. Finally there is significant correlation with neutrophilic infiltration with necrotizing features with low APGAR. There is significant correlation between fetal placental ratio and low APGAR and early neonatal death. p<0.01. These morphological and histological changes of placenta and its relation to fetal morbidity and mortality is more pronounced in high risk pregnancies. There is significant association between abnormal uterine artery waveforms and high risk pregnancies .There is significant correlation between Uterine artery Doppler early diastolic notch and low APGAR in preeclampsia. There is borderline association between Uterine artery Doppler, elevated systolic diastolic ratio and low APGAR in preeclampsia. There is significant association between abnormal uterine artery Doppler waveforms and stillbirth in preeclampsia. Gross features – there was no significant correlation with calcification, other morphological features such as both the type of placenta, septal cyst, true knot, , with fetal outcome.(P > 0.01) In our study only two cases had single umbilical artery, among which one died due to cardiac anomaly. Neonatal mortality was observed on the later part of 1st week of delivery in cases where we see such histomorphological changes of placenta. The morbidity and mortality can be reduced by initiating judicial better neonatal care and better antibiotic coverage once we see those histomorphological changes, not waiting for the baby to exhibit symptoms or signs. Hence the present study is important as on application, it can reduce neonatal morbidity and mortality. CONCLUSION: This study is an endeavour to assess the possible probable link of morphological and histopathological changes in placenta and the fetal outcome. Many such studies pile up, days may not be for off when a definite link can be proved in a very positive way. This will help to save many babies. Through examination of the delivered placenta can provide a better picture of the intrauterine environment of the fetoplacental unit than a placental bed biopsy. The ability to routinely identify failure of uteroplacental vascular adaptation, fibrinoid necrosis, atherosis, persistence of endovascular trophoblasts, thrombosis and chronic vasculitis in the basal plate can clarify the nature and mechanisms involved in pregnancy compromise. Many studies are upcoming for placenta screening for high risk pregnancies by using a combination of ultrasound and blood tests to screen high risk pregnant mothers for placental damage. By completing these non invasive tests, most high risk mothers can be reassured that their placenta is formed and functioning properly, so they can expect a healthy pregnancy. This is an important first step in identifying placental abnormalities in early pregnancy, at a time when a number of interventions can be used to improve outcomes for those with the highest risk. This study will lead the way for future research in placenta screening and help us provide quality care for all mothers