Association of First-trimester Placental Thickness by Ultrasound and the Risk of Preeclampsia or Small Gestational Age

Abstract

Introduction and aim: Placenta play a crucial role in normal fetal development. Any deviation from normal could firstly affect placenta and subsequently represented on the fetus. Thus, different placental measurements could be used as predictors for complicated pregnancy. The current work was designed to examine the potential association between maximum placental thickness in the first-trimester and the subsequent risk of preeclampsia or the risk of the delivery of small for gestational age neonate

Methodology: This study included 150 pregnant women with singleton pregnancy. All women were assessed by full medical history and physical examination. Clinical examination preceded the routine laboratory investigations. Finally, an ultrasound was performed and repeated each weak from 11 to 14 gestational weeks to determine crown-lump length and measure maximum placental thickness. All females were followed till delivery, with documentation of preeclampsia development and/or delivered a small for gestational age (SGA) neonate.

Results: We excluded 4 women from the study due to abortion.  Preeclampsia with preterm delivery recorded for 5 females, preeclampsia without preterm delivery developed in13 females, preeclampsia with SGA (5 females) and SGA among 7 females; and 116 non-complicated pregnancies. Cesarean delivery was performed for 80 females (54.8%). There was significant progressive increase of maximum placental thickness (MPT) from the 11^th to the 14^th weeks of gestation. Preeclampsia was associated with significant increase of MPT, while SGA was associated with significant reduction of it. The area under the curve was more than 0.7. For preeclampsia, the sensitivity was 88.89% at cutoff value > 1.0; while for SGA, the sensitivity was 100.0% at cutoff value ≤0.94.

Conclusion: Maximum placental thickness at 11 to 14 weeks provides a good predictive power for development of preeclampsia and delivery of small for gestational age. This permits early therapeutic intervention.