Comparison of Placental Three-Dimensional Power Doppler Vascular Indices and Placental Volume in Pregnancies with Small for Gestational Age Neonates

Abstract

This prospective observational study aimed to compare the changes in placental vascular indices and placental volume using three-dimensional power Doppler (3DPD) ultrasound in pregnancies with small for gestational age (SGA) neonates. We enrolled 396 women with singleton pregnancies from September 2013 to June 2016. Placental vascular indices, including the vascularization index (VI), flow index (FI), and vascularization flow index (VFI), and placental volume were obtained using 3DPD ultrasound in the first and second trimesters. Of the enrolled women, 21 delivered SGA neonates and 375 did not. In the first trimester, the SGA group had a significantly lower mean FI (25.10 ± 7.51 versus 33.10 ± 10.97, p < 0.001) and VFI (4.59 ± 1.95 versus 6.28 ± 2.35, p = 0.001) than the non-SGA group. However, there was no significant difference in the placental volume between the two groups during the first trimester. In the second trimester, the SGA group also had a significantly lower mean FI (27.08 ± 7.97 versus 31.54 ± 11.01, p = 0.022) and VFI (6.68 ± 1.71 versus 8.68 ± 3.09, p < 0.001) than the non-SGA group. In addition, a significantly smaller placental volume was noted in the SGA group (104.80 ± 24.23 cm3 versus 122.67 ± 26.35 cm3, p = 0.003) than in the non-SGA group during the second trimester. The results showed that a decreased placental VFI occurred earlier than a decreased placental volume in SGA pregnancies.

Smoking and Smoking Cessation in the Risk for Fetal Growth Restriction and Low Birth Weight and Additive Effect of Maternal Obesity

“…The comparison of our results from this and our previous research is important, because FGR often coexists with PE, and in the pathogenesis of both cases, the role of placental ischemia resulting from abnormal spiral arterial transformation in early pregnancy is taken into consideration [9,10,15]. In our cohort, 18.2% of the women who developed PE and 1.4% of women who remained normotensive (p < 0.0001) gave birth to newborns with FGR diagnosed during pregnancy.…”

“…The mechanisms of the relationships found (between smoking in the first trimester and the risk of birth weight <10th percentile, LBW, and FGR) are not fully understood. The main factors affecting fetal growth include the placenta, which guarantees the flow of nutrients to the fetus [14][15][16]. Factors causing hypoxia and reductions of blood flow in the placenta may increase the risk of FGR, SGA, and LBW [2,7].…”

“…Fetal growth restriction (FGR) was diagnosed based on ultrasound in pregnancy (all cases were recorded, regardless of phenotype) [14][15][16]. FGR was defined as the fetus' inability to reach its full growth potential and was diagnosed based on ultrasound in pregnancy.…”

“…The effect of multi-direction impacts of different components of cigarette smoke on complex multi-factor processes associated with the fetal growth are difficult to assess [12,13]. In addition to genetic factors, the main factors affecting fetal growth include the placenta, which guarantees the flow of nutrients to the fetus [14][15][16], as well as the mother's nutritional status [13] and environmental factors [14]. Blood flow reductions in placenta, placental ischemia, hypoxia, and intensified oxidative stress and inflammation have been identified as key elements of pathogenesis of adverse fetal outcomes.…”

“…This could suggest that obesity can also intensify the relations of smoking to fetus growth reduction. Thirdly, an analysis of the available literature indicates that the studies often cover one category of newborn weight [14,15,26].…”