Abstract
Objective To investigate the diagnostic accuracy of the placental thickness measured by ultrasound sonography test (USG) in detecting intrauterine growth restriction (IUGR) babies in the third trimester of pregnancy, keeping IUGR (by parameters using Hadlock) as the gold standard. Methods and materials This cross-sectional study was conducted at the radiology department of KRL Hospital from August 5, 2020, to October 25, 2021. Informed written consent was also obtained from each patient, and the hospital's ethical committee approved the study. Three hundred and sixty-two (N=362) pregnant women patients knowing of their last menstrual period, age group 20-35 years, BMI usual, and 24 weeks gestation were included. The patient's complete history was taken by clinical examination and then ultrasound was carried out to measure the placental thickness. At 24, 32, and 36 weeks, the thickness of the placenta was assessed. The Hadlock method was used to compute the predicted fetal weight by measuring biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) on the GC Logiq P/6 three-dimensional machine (GE, Tampa, FL). SPSS v 23 (IBM Corp., Armonk, NY) was used to calculate the mean and standard deviation from the collected data. Results A total of 362 patients who presented in the radiology department for antenatal ultrasound in the third trimester were recruited in our study. The mean age was 27.26 ± 4.21 years (20-35 years). In our study, the mean placenta thickness at 24 gestation weeks was 24.55 ± 0.79 mm, at 32 gestation weeks was 31.84 ± 1.34 mm, and at 36 gestation weeks was 35.54 ± 2.78. Thus, ultrasound's sensitivity, specificity, positive predictive value, and negative predictive value to determine IUGR by placental thickness was 86.30%, 86.70%, 75%, and 92%, respectively. The diagnostic accuracy of ultrasound incorrectly estimating low placental thickness was 86.40%. Conclusion Between 24 and 36 weeks of pregnancy, placental thickness rises almost linearly. As a result, measuring placental thickness and other factors is critical for estimating fetal age, particularly in the late second and early third trimesters, when the exact duration of pregnancy is uncertain. Placentas that were less than 29 mm thick at 32 weeks and 31 mm thick at 36 weeks were related to higher morbidity, lower Apgar scores, and more nursery admissions.