Second and Third Trimester Placental Thickness: Correlation with Placental and Birth Weights


ABSTRACT:BACKGROUND:The placenta is a materno-fetal organ; it is closely related to the fetus and the mother, it acts like a mirror, reflecting the statuses of both the mother and the fetus. Placental evaluation by ultrasound has been used to characterize placental morphologic changes as the placenta matures. Using different parameters such as placental thickness, weight, and volume have exhibited significant and positive relationship with gestation and birth weight.OBJECTIVE: To investigate the relationship between placental thickness during the second and third trimesters and placental and birth weight. METHODS: This Prospective Longitudinal study involved pregnant women who presented at Al-Yarmouk Teaching Hospital antenatal clinic. All recruited women were assessed at their 1st trimester visit for baseline demographic and obstetrical data. At the second and third trimesters, maternal weight, weight gain, body mass index, body mass index gain, placental thickness measured by ultrasound, and thickness change were recorded. Statistical analysis was performed to establish the degree of relationship between placental thickness and placental and birth weights. RESULTS: Of 150 recruited participants, 100 women were able to complete the study. The mean maternal age was 32.1±4.2 years. Ultrasonographic measures of placental thickness in the second and third trimesters and thickness changes between them were 2.44±0.57, 3.58±0.59 and 1.14±0.38 cm respectively. Values of mean birth and placental weights were 3433± 350.99, and 457.95±46.82 grams respectively. A significant positive correlation was found between placental thickness and birth weight in the second and third trimesters (r=0.0237, p=0.018, r=0.399, p<0.001) respectively.CONCLUSION: According to the present study, birth weight has a positive correlation with both second and third trimester placental thickness; however, placental thickness change could not predict low or high birth weights.