Clinical and Histological Associations of Chronic Inflammatory Lesions in Preterm Placentas: Uncovering the Hidden Dangers.

BACKGROUND: Chronic placental inflammatory lesions (CPIL) include chronic deciduitis (CD), villitis of unknown etiology (VUE), and chronic chorioamnionitis (CCA). The frequency of these lesions and their relationship with various clinicopathological parameters in preterm birth (PTB) is presented. MATERIAL AND METHODS: Preterm placentas from April 2018 to December 2020 were reviewed for presence of CPIL. PTB was classified as spontaneous, indicated, or mixed phenotype. The association of CPIL with clinical parameters like gestational age, birth weight, obstetric complications, and placental parameters like placental dimensions, weight, vascular malperfusion, acute inflammatory lesions, and basal plate myometrial fibers were analyzed. RESULTS: The study included 538 preterm placentas with 54.3% from indicated PTB. CD was more common (28.4%) than VUE (17.8%) and CCA (12.6%). CD showed significant association with VUE and CCA (both P = .0001) and VUE with CCA (P = .0001). CD was more common in indicated PTB (33.8%, P = .002) and associated with lower birth weight (1591 g vs 1705 g, P = .003), lower placental weight (270.7 g vs 296.9 g, P = .004), length (14.2 cm vs 14.8 cm, P = .006), breadth (11.7 cm vs 12.2 cm, P = .007), maternal vascular malperfusion (P = .004), and basal plate myometrial fibers (P = .02). High-grade and multifocal low-grade VUE was associated with reduced placental length (13.9 cm vs 14.6 cm, P = .02)and breadth (11.5 cm vs 12.1 cm, P = .01). CCA did not show any other association. CONCLUSION: CPIL are common in PTB and their coexistence suggested a common pathogenic mechanism. Placental examination is the only definite way to identify as they lack clinical signs and symptoms. The smaller placental size associated with these lesions may suggest alter mechanisms for adverse pregnancy outcomes.

Associations Between the Features of Gross Placental Morphology and Birthweight.

The placenta plays a critical role in regulating fetal growth. Recent studies suggest that there may be sex-specific differences in placental development. The purpose of our study was to evaluate the associations between birthweight and placental morphology in models adjusted for covariates and to assess sex-specific differences in these associations. We analyzed data from the Stillbirth Collaborative Research Network's population-based case-control study conducted between 2006 and 2008, which recruited cases of stillbirth and population-based controls in 5 states. Our analysis was restricted to singleton live births with a placental examination (n = 1229). Characteristics of placental morphology evaluated include thickness, surface area, difference in diameters, shape, and umbilical cord insertion site. We used linear regression to model birthweight as a function of placental morphology and covariates. Surface area had the greatest association with birthweight; a reduction in surface area of 83 cm2, which reflects the interquartile range, is associated with a 260.2-g reduction in birthweight (95% confidence interval, -299.9 to -220.6), after adjustment for other features of placental morphology and covariates. Reduced placental thickness was also associated with lower birthweight. These associations did not differ between males and females. Our results suggest that reduced placental thickness and surface area are independently associated with lower birthweight and that these relationships are not related to sex.

Three-dimensional sonographic assessment of placental volume and vascularization in pregnancies complicated by hypertensive disorders.

OBJECTIVES: The purpose of this study was to evaluate the association between placental volumes, placental vascularity, and hypertensive disorders in pregnancy. METHODS: A prospective case-control study was conducted between April 2011 and July 2012. Placental volumes and vascularity were evaluated by 3-dimensional sonographic, 3-dimensional power Doppler histographic, and 2-dimensional color Doppler studies. Pregnant women were classified as normotensive or hypertensive and stratified by the nature of their hypertensive disorders. The following variables were evaluated: observed-to-expected placental volume ratio, placental volume-to-estimated fetal weight ratio, placental vascular indices, and pulsatility indices of the right and left uterine and umbilical arteries. RESULTS: Sixty-six healthy pregnant women and 62 pregnant women with hypertensive disorders were evaluated (matched by maternal age, gestational age at sonography, and parity). Placental volumes were not reduced in pregnancy in women with hypertensive disorders (P > .05). Conversely, reduced placental vascularization indices (vascularization index and vascularization-flow index) were observed in pregnancies complicated by hypertensive disorders (P < .01; P < .01), especially in patients with superimposed preeclampsia (P = .04; P = .02). A weak correlation was observed between placental volumes, placental vascular indices, and Doppler studies of the uterine and umbilical arteries. CONCLUSIONS: Pregnancies complicated by hypertensive disorders are associated with reduced placental vascularity but not with reduced placental volumes. These findings are independent of changes in uterine artery Doppler studies. Future studies of the prediction of preeclampsia may focus on placental vascularity in combination with results of Doppler studies of the uterine arteries.

Two-dimensional (2D) placental ultrasound measurements - The correlation with placental volume measured by magnetic resonance imaging (MRI).

INTRODUCTION: Information about placental size in ongoing pregnancies may aid the identification of pregnancies with increased risk of adverse outcome. Placental volume can be measured using magnetic resonance imaging (MRI). However, this method is not universally available in antenatal care. Ultrasound is the diagnostic tool of choice in pregnancy. Therefore, we studied whether simple two-dimensional (2D) ultrasound placental measurements were correlated with placental volume measured by MRI. METHODS: We examined a convenience sample of 104 ongoing pregnancies at gestational week 27, using both ultrasound and MRI. The ultrasound measurements included placental length, width and thickness. Placental volume was measured using MRI. The correlation between each 2D placental ultrasound measurement and placental volume was estimated by applying Pearson's correlation coefficient (r). RESULTS: Mean placental length was 17.2 cm (SD 2.1 cm), mean width was 14.7 cm (SD 2.1 cm), and mean thickness was 3.2 cm (SD 0.6 cm). Mean placental volume was 536 cm3 (SD 137 cm3). The 2D ultrasound measurements showed poor correlation with placental volume (placental length; r = 0.27, width; r = 0.37, and thickness r = 0.13). DISCUSSION: Simple 2D ultrasound measurements of the placenta were poorly correlated with placental volume and cannot be used as proximate measures of placental volume. Our finding may be explained by the large variation between pregnancies in intrauterine placental shape.

Fetal and placental development in early gestation of hyper-prolific sows.

Modern hyper-prolific sows produce large litters with a high within-litter variation in birth weight and an increased number of low-birth-weight piglets per litter with higher mortality rates and lower growth rates compared to heavier littermates. This study aimed to describe fetal development in hyper-prolific sows, to characterize differences between large and small fetuses, and to determine when within-litter variation in fetal weight can be detected. Forty-seven multiparous sows were blood-sampled and slaughtered at day 28, 33, 45, 50, and 56 of gestation. Number of fetuses were counted, fetal body and organ weights were measured, and the intrauterine positioning was recorded. Length, width, and area of each placenta was measured and the fetus weight/placental weight ratio was calculated. The umbilical cords of the smallest, medium and the largest fetus of each litter were sampled for histological analysis. In total measurements were obtained for 1161 fetuses. The results revealed no difference in fetal survival between the gestational days (P > 0.05). Intrauterine positioning near the cervix significantly reduced fetal weight at day 56 (P < 0.05). Total litter weight and average fetal weight increased with gestational age and individual fetal weight was negatively affected by litter size from day 33 and onwards (P < 0.05). The coefficient of variation for within-litter variation in fetal weight was higher at day 28 compared to the other gestational days (P < 0.05). Relative brain- and heart weights decreased from day 28-56 (P < 0.001). Small fetuses had relatively heavier brains and hearts at day 45, 50 and 56 (P < 0.001). Size of placenta, fetus weight/placental weight ratio and length of umbilical cord increased with gestational age (P < 0.001). There was a positive correlation between size of placenta and weight of individual fetus (P < 0.001), the weight of the fetus was positively correlated with umbilical cord length (P < 0.001) and the umbilical cross-sectional area was correlated to fetal weight at day 56 (P < 0.01). Individual fetal weight was positively correlated to the fetus weight/placental weight ratio (P < 0.001). In conclusion, fetal growth was affected by litter size, placental weight, and -area, and umbilical cord length. Lightweight fetuses were characterized by having placentas with lower weight and area and shorter umbilical cords. Lastly, within-litter variation in fetal weight was detectable at day 28, and the coefficient of variance remained stable from day 33-56.

The effect of dietary omega-3 fatty acid supplementation on fetal growth, piglet birth weight and plasma fatty acid concentrations, using docosahexaenoic acid in early gestation in sows.

The objective of the study was to test the effect of the omega-3 fatty acid docosahexaenoic acid (DHA) on fetal and placental development as well as the birth weight of piglets. A total of 238 multiparous sows were allocated to either a control diet group or a DHA diet group with an omega-6 to omega-3 ratio of 9.8 and 2.4, respectively, from mating to day 43 of gestation. A blood sample was collected and back fat thickness was measured prior to mating, on days 14, 42 and 112 of gestation. On day 43 of gestation, 14 sows were slaughtered and measurements of fetuses and placentas were taken. Piglets in some litters were weighed individually at farrowing. Dietary treatment did not affect fetal characteristics and back fat thickness (P > 0.05). Dietary treatment increased the plasma concentrations of total omega-3 fatty acids in sows (P < 0.05). Sows fed the DHA diet had a shorter gestation length compared to the control sows (P < 0.05), but the number of born piglets was not affected (P > 0.05). The average piglet birth weight and the within-litter variation in birthweight were unaffected by dietary DHA (P > 0.05), however, sows fed DHA diet had fewer piglets under 800 g at birth compared to control sows (P < 0.05). In conclusion, addition of DHA decreased the dietary ratio of omega-6 to omega-3 fatty acids, increased plasma n-3 fatty acid concentrations in sows and decreased the number of piglets weighing under 800 g at birth.

Umbilical cord blood PBDEs concentrations in relation to placental size at birth.

Previous studies have linked prenatal polybrominated diphenyl ether (PBDE) exposure to adverse birth outcomes. Reductions in placental size might mediate those adverse effects. We examined whether umbilical cord blood PBDEs concentrations were associated with placental size at birth. A total of 121 mother-newborn pairs residing in Wenzhou were enrolled in this study. Concentrations of 19 PBDEs in umbilical cord blood were determined by gas chromatography tandem mass spectrometry (GC-MS). Placental length, breadth and surface area was measured by medical professionals after delivery. BDE-206, 207, 208, 209 and the total of 19 PBDE congeners concentrations were negatively associated with placental length, breadth and surface area. Our results suggest that prenatal PBDEs exposure may suppress placental growth, resulting in reduced placental size.