Ultrasound Measurement of Placental Thickness: A Reliable Estimation of Gestational Age in Normal Singleton Pregnancies in Nigerian Women

PURPOSE: The aim of this article is to evaluate the accuracy of placental thickness (PT) in determination of gestational age (GA) in normal singleton foetuses. MATERIALS AND METHODS: The study was a cross-sectional descriptive study which recruited consecutively a total of 406 pregnant women with singleton pregnancies (at 15–40 weeks of gestation), referred for routine obstetric ultrasound (US) scan at the National Hospital, Abuja from October to December 2019. Biparietal diameter (BPD), femur length (FL), head circumference (HC), abdominal circumference (AC), and PT were measured using standard protocols. All measurements were calculated by taking three best measurements, and the mean of the measurements was taken and recorded for each participant. Pearson’s correlation analysis was computed to determine linear relationships between variables. A significant statistical level was determined at a critical value of P < 0.05. RESULTS: The mean age was 31.8 ± 4.8 years. The mean PTs in the second and third trimesters were 23.2 ± 3.1 and 34.1 ± 3.7 mm, respectively. PT had a linear relationship and a statistically significant positive correlation (r=0.99, P = 0.00) with GA. There was also a statistically significant positive correlation between PT on the one hand, and BPD, AC, HC, FL, PT, and GA, on the other hand. CONCLUSION: There was a significant and strong positive correlation between PT and GA. The study shows that US measurement of PT is a reliable method of estimating GA in singleton pregnancies in Nigeria.