Effects of polyhydramnios and oligohydramnios on the calculation of estimated fetal weight

Objective: In this study we investigate the effects of the amount of amniotic fluid on the calculation of estimated fetal weight. Material and Method: Determinations were done in 150 gravid women who admitted to Bozok Univercity Research and Practice Hospital from January 2017 to June 2019. These patients were in their 34 and 41th gestational weeks and all of them delivered in maxium 48 hours following hospitalization. Demographic data of patients, maternal BMI (kg/m2), amniotic fluid volüme, ultrasonographic estimated fetal weight and the actual birth weight of the newborn has been reached. In the study a single, alive pregnancies were included. Fetal anomalies, multiple pregnancies, dead fetuses, rupture of amniotic membrane cases excluded from the study. Ultrasonographic assessment of all pregnant women carried out by the same assistant. From all patients informed consent for initiatives taken at admission are taken form. For statistical analysis, Statistical Package for Social Sciences (SPSS Inc; Chicago, IL, USA) 20.0 program is used. Results: In our study differency between estimated fetal weight and actual birth weight is found 186.06±121.03 in control group, 235.44±204.77 in oligohydramnios group and 277.82±160.88 in polyhydramnios group. When considering maternal sex of the fetus and placental position there is no statistically significant effect to the correct estimation of fetal weight found. Of the parameters measured, in pregnant women with BMI<30 ultrasound estimated fetal weight was closer to the actual birth. Discussion: The correct prediction of fetal weight is of great importance becouse of the potential risk estimation for the mother and the newborn and in deciding the mode of delivery. For this reason variables that affect the probability of errors in ultrasonographic measurements should be considered in advance, In our study we found differency between estimated fetal weight and actual birth weight is greater in oligohydramnios and polyhydramnios cases. (p= 0.015) Keywords: Estimated fetal weight, Actual birth weight, Oligohydramnios, Polyhydramnios