Birthweight Placental Weight Research Articles

Association between trimester-specific prenatal air pollution exposure and placental weight of twins

IntroductionThis study investigates the association between maternal exposure to particulate matter (PM10) and nitric dioxide (NO2) during the first, second and third trimester and placental weight and birth weight/placental weight (BW/PW) ratio in twins at birth. MethodsCross-sectional data of 3340 twins from the East Flanders Prospective Twin Survey was used. Air pollutant exposure was estimated via spatial temporal interpolation. Univariable and multivariable mixed model analyses with a random intercept to account for the relatedness of newborns were conducted for twins with separate placentas. Twin pairs with one placental mass were studied with linear and logistic regression. ResultsIn the third trimester, for each 10 μm/m3 increase in PM10 or NO2 placental weight decreased −19.7 g (95%-C.I. −35.1; −4.3) and −17.7 g (95%-C.I. −30.4; −0.5) respectively, in moderate to late preterm twins with separate placentas. Consequently, BW/PW ratio increased with higher air pollution exposure. PM10 exposure in the last week of pregnancy was associated with a higher odds ratio (OR) of 1.20 (95%-C.I. 1.00; 1.44) for a “small for gestational age placenta” (placental weight <10th percentile). Conversely, first trimester air pollutant exposure was associated with lower ORs of 0.55 (95%-C.I. 0.35; 0.88) and 0.60 (95%-C.I. 0.42; 0.84). DiscussionThe association of PM10 and NO2 on placental weight is trimester-specific, differs for twins with one versus two placentas and is most pronounced in moderate to late preterm twins. Longitudinal studies are needed to better understand the relationship between air pollutant exposure and placental weight evolution across different trimesters.

The effects of exercise during pregnancy on placental composition: A systematic review and meta-analysis.

Morphological changes to the placenta occur as the demands of the foetus increase throughout gestation. Physical activity during pregnancy is known to benefit both the mother and infant, however the impact of antenatal exercise training on placental development is less known. The aim of this systematic review and meta-analysis was to investigate the effects of exercise training during pregnancy on measures of placental composition. Six electronic databases were searched from inception to June 2021 for studies comparing regular antenatal exercise with either usual maternal care or no exercise for its effect on measures of placental morphological composition. Meta-analyses were performed for placental weight and the placental weight to birthweight (PWBW) ratio. Seven randomised controlled trials and two cohort studies were included in the systematic review and meta-analysis (n=9). There was no significant difference in placental weight (mean difference (MD)=-9.07g, p=0.42) or the PWBW ratio (MD=0.00, p=0.32) between exercise and control groups. Parenchymal tissue volume was higher, represented by an increase in villous tissue, and non-parenchymal volume was lower in women who exercised regularly compared to those that were not exercising during pregnancy. Exercise training during pregnancy may not alter placental weight or the PWBW ratio. However, findings from this review indicate that antenatal exercise training can promote advantageous morphological changes to placental tissues.

Association between maternal hemoglobin concentration and placental weight to birthweight ratio: The Japan Environment and Children's Study (JECS)

IntroductionPast studies have shown that maternal anemia is associated with a heavy placenta or a higher placental weight/birthweight (PW/BW) ratio. Although these findings suggest a non-linear relationship between maternal hemoglobin concentration and PW/BW ratio, this relationship has not been closely examined. MethodsWe evaluated 83,354 singletons and their mothers in a nation-wide birth cohort study, the Japan Environment and Children's Study (JECS). The associations between maternal hemoglobin concentration and placental weight, birthweight, and PW/BW ratio were assessed. ResultsMean placental weight was significantly higher in women with moderate or severe anemia (576 [183] g), but not in women with elevated hemoglobin levels (564 [117] g), compared with in women with normal hemoglobin levels (560 [115] g). In contrast, mean PW/BW ratio was significantly higher in women with moderate or severe anemia (0.190 [0.049]) or elevated hemoglobin levels (0.189 [0.033]) than in women with normal hemoglobin levels (0.185 [0.033]). In a regression analysis with cubic spline, a U-shaped relationship was found between maternal hemoglobin concentration and PW/BW ratio. DiscussionWe demonstrated non-linear and concentration-dependent relationships between maternal hemoglobin concentration and placental weight, birthweight, and PW/BW ratio. Although the mechanisms underlying these associations are not fully understood, we suggest that low or elevated hemoglobin concentration may lead to placental compensatory hypertrophy and fetal growth restriction. Prevention and proper management of anemia before and during pregnancy are important for a well-functioning placenta and favorable fetal growth.

The Relationship Between Pregnancy Exposure to Antidepressant and Atypical Antipsychotic Medications and Placental Weight and Birth Weight Ratio: A Retrospective Cohort Study.

Psychotropic medication use in pregnancy has been associated with altered fetal growth. The aim of this study was to investigate the relationship between placental weight and placental weight-to-birth weight (PBW) ratio, as a potential marker of placental efficiency, and medication use in a cohort of women with severe mental illness in pregnancy. A retrospective database analysis was carried out on a cohort of pregnant women with severe mental illness (242 singleton pregnancies) and grouped according to their psychotropic medication use. Demographic, obstetric, neonatal, and psychiatric variables were analyzed using t tests, χ, analysis of variance, univariate, binary, and multiple regression adjusting for potential confounders. Multiple regression analysis demonstrated a mean adjusted increase in placental weight of 114 g (95% confidence interval [CI], 60.2-165.6 g) in women taking antidepressant medication and 113 g (CI, 65.1-162.8 g) in women taking combined antidepressant and atypical antipsychotic medication in pregnancy. There was also a significantly elevated PBW ratio in these 2 medication groups (B 0.02: CI, 0.006-0.034; and B 0.025: CI, 0.012-0.038). Binary regression, adjusted for sex and gestational age, showed a significant odds ratio of 4.57 (95% CI, 2.17-9.62) for PBW ratio of greater than 90% in those taking antidepressant medication, either alone or in combination, compared with unmedicated women. The use of antidepressant medication, alone or in combination, has a significant effect on placental weight and PBW ratio after adjusting for confounding variables. Given that this may reflect adverse effects on intrauterine growth and have possible long-term implications for the fetus, further research is warranted to confirm these findings.

Correlation between birth weight and placental weight in healthy and diabetic puerperae

ObjectiveThe birth weight/placental weight ratio has an important predictive value for perinatal mortality and morbidity and for cardiovascular diseases in adult life. In this study, we compared the birth weight/placental weight (BW/PW) ratio and the correlation between the two parameters in diabetic women with that observed in healthy women. Materials and MethodsA total of 347 consecutive newborn infants from healthy puerperae, 164 newborns from puerperae with gestational diabetes, 148 newborns from puerperae with preexisting type 1 diabetes, and 40 newborns from puerperae with preexisting type 2 diabetes have been studied from the White population of Rome. The research project was approved by the Institutional Review Board and informed written consent was obtained from the participating mothers. ResultsThe BW/PW ratio is higher, and the correlation between the two parameters is lower in all classes of diabetes as compared to healthy puerperae. A remarkably low correlation is observed in preexisting diabetes pointing to a dissociation of fetal growth from placental growth. DiscussionIn diabetic pregnancy the BW/PW ratio is higher, and the correlation between birth weight and placental weight is lower in all classes of diabetic as compared to healthy puerperae pointing to a relative dissociation between the two parameters. It has been suggested that the increase of glycemic levels in diabetic pregnancy predisposes to important diseases in adult life. The dissociation of BW from PW in infants of diabetic pregnancy could be a predictor of the risk for such diseases of adult life.

Effect of ADA1 mother–fetus and wife–husband phenotypic differences on the ratio birth weight/placental weight in fertile women and on reproductive success in couples with RSA

To study the effect Adenosine Deaminase locus 1 (ADA(1)) mother-fetus and wife-husband phenotypic differences on the ratio Birth Weight/Placental Weight (BW/PW) in fertile women and on reproductive success in couples with repeated spontaneous abortion (RSA). 209 couples with primary RSA and a consecutive series of 379 healthy puerperae with their newborn infants from the White Caucasian population of central Italy were studied. In primary RSA women reproductive success was indicated by the presence of at least one live-born infant within 5 years of follow up. Two way contingency tables were analyzed by chi-square. The proportion of primary RSA couples with at least a live-born infant shows the highest value in couples mother ADA(1)1/father carrier of ADA(1)*2 allele (55.2%) and the lowest value in reciprocal couples mother carrier of ADA(1)*2 allele /father ADA(1)1 (18.7%) (O.R. = 5.33; P = 0.023). The highest ratio BW/PW is observed in the class mother ADA(1)1/newborn carrier of ADA(1)*2 allele while the lowest ratio is observed in the reciprocal class mother carrier of ADA(1)*2 allele/ newborn ADA(1)1. Differences between mother and fetus in ADA(1) phenotype may influence the ratio BW/PW in healthy women and reproductive success in RSA women.

The effect of umbilical venous constriction on placental development, cord length and perinatal outcome

Background Umbilical vein constriction at the fetal abdominal inlet is a common finding after week 13, when the period of umbilical herniation is brought to an end. Aims To test the hypothesis that a constricting umbilical ring within physiological ranges affects fetal hemodynamics by either pooling blood in the placenta or restricting nutrient transfer to the fetus and thus shift the birthweight/placental weight (BW/PW) ratio. A constriction could also cause pressure changes and elongation of the cord and possibly be a disadvantage during labour. Study design Cross-sectional. Subjects 359 Low-risk singleton pregnancies at 13–40 weeks of gestation. Outcome measures Standard deviation score ( z-score) and regression analysis were used to determine the effect of umbilical vein constriction (expressed by increased blood velocity) on birthweight/placental weight ratio (BW/PW), cord length, Apgar score and emergency delivery due to fetal distress. Results Umbilical venous constriction had a mild but significant effect on BW/PW in male ( p=0.018) but not in female fetuses. Increased constriction was also associated with increased length of the cord but only in female fetuses ( p=0.019). Cord length was positively related to birthweight and placental weight, but an increased length of the cord was also associated with decreasing BW/PW ratio for the male fetuses only ( p=0.044). Increasing degree of venous constriction was associated with Apgar score ≤7 at 1 ( p=0.009) but not at 5 min after birth and was not associated with emergency delivery. Conclusion Physiological umbilical venous constriction exerts a mild but significant gender-specific hemodynamic impact on intrauterine development.

Variation in size at birth in infants born small for gestational age in Lithuania

The aim of this study was to describe the heterogeneity in body proportions of infants born small for gestational age (SGA), defined by birthweight, and to study the relationship of placental size with neonatal anthropometric measurements. Anthropometry was evaluated in 107 symmetrically and asymmetrically growth‐retarded infants born SGA (birthweight &lt;−2 SD) and compared with 181 appropriate‐for‐gestational age infants (AGA; birthweight and length ± 2 SD). Study children were born at Kaunas University Hospital during the period from 1 January 1998 to 25 August 2000. Two‐thirds of SGA children were light (SGAW) and one‐third was both light and short (SGAWL) for gestational age. Infants in both SGA groups were significantly leaner than AGA children. SGAWL infants had significantly larger heads in relation to their length compared with SGAW and even AGA children, probably indicating a brain‐sparing effect. SGAWL children had the lowest mean placental weight, but the highest placental weight to birthweight (PW/BW) ratio. The PW/BW ratio was inversely correlated with most infant measurements; the strongest negative relationship was observed with birthlength and lower leg length. Conclusion: There is heterogeneity in children born SGA, defined by birthweight. It is suggested that the two SGA groups represent the continuum of intrauterine growth retardation, with an initial reduction in trophic growth and a subsequent retardation of linear growth. The PW/BW ratio is a strong indicator for impaired prenatal linear growth.

The placental weight-birthweight relationship.

SUMMARYThe placental weight‐birthweight relationships were analyzed by race, sex and the survival status of the babies for some 17,000 cases.The difference in mean placental weights between Negroes and Whites and between sexes are explained by differences in the mean birthweights between the groups.The placental weight‐birthweight relationships between the races and the sexes are similar in all aspects–slopes, intercepts, and curvilinearity.When the data for the races and the sexes are combined, the placental weight‐birthweight associations for the stillbirths and the neonatal deaths are found not to be significantly different for infants of similar birthweight. The mean placental weights between the groups are not demonstrably different; weight relationships for both groups are best expressed by straight lines rather than curves, and the two lines are parallel.The placental weight‐birthweight association for infants who survived the neonatal period, on the other hand, is best represented by a line which is slightly but demonstrably curved–concave upward.The mean placental weights of both death groups are greater than those of the survival group, for infants of the same birthweight in the range 2,000–4,000 grams.The expected placental weight for any specified birthweight can be calculated from these data.RéSUMÉLes relations entre le poids du placenta et le poids de naissanceLes relations entre le poids du placenta et le poids de naissance ont été analysées par race, sexe, et l'état de survie des bébés dans 17.000 cas environ.Les differences dans les poids moyens du placenta entre nègres et blancs et entre les sexesLes courbes représentant les relations entre poids du placenta et poids de naissance sontLorsque les chiffres pour les races et les sexes sont combinés les associations poids du placenta‐poids de naissance pour les morts‐nés ne pas différent de façon significative de celles des enfants de poids de naissance similaire. Le poids moyen du placenta ne se distingue pas clairement entre les groupes; les relations de poids pour les deux groupes sont mieux représentées par des droites que par des courbes, et les deux lignes sont paralleles.L'association poids du placenta‐poids de naissance pour les enfants qui ont survécu à la période néonatale, d'autre part, est mieux représentée par une ligne légèrement mais clairement incurvee–concave vers le haut.Le poids moyen du placenta pour les deux groupes ou la mort est survenue est supérieur à celui du groupe des survivants, pour les enfants du même poids de naissance entre les limites de 2.000 à 4.000 grammes.On peut calculer le poids présumé du placenta pour un poids de naissance donné d'après ces données.RESUMENRelaciones entre peso natal y peso placentalSe analizaron las relaciones entre el peso de la placenta y el peso natal según raza, sexo, y supervivencia de los niños, en 17, 000 casos aproximadamente.Las diferencias en el peso medio de la placenta en Negros y Blancos corresponden con diferencias en el peso medio al nacimiento de los dos grupos. Las relaciones entre el peso placental y el peso natal entre las razas y los sexos son parecidas de todo punto de vista; inclinaciones, intercepciones y curvilinearidad.Cuando se unen todos los datos por las razas y los sexos, se halla que las asociaciones entre el niñso placental y el peso natal por los partos con nino muerto y las muertes de niños recién nacidos difieren muy poco en niños de peso natal parecido. No hay ninguna diferencia en el peso placental medio de los dos grupos. Las relaciones enxre los grupos se representan mejor por lineas rectas que, por curvas, y las dos lineas son paralelas.En cambio, la asociación entre el peso placental y el peso natal en los niños que sobrevivie‐ron al perlodo neonatal se representa mejor por una linea un poco corva‐ con curva concava que se inclina ligeramente hacia arriba.El peso placental medio de los dos grupos de niños muertos es mayor que el de los niños en el grupo que sobrevivió, por infantes del mismo peso natal de 2,000 a 4,000 gramas.Es posible leer el peso placental esperado por cualquier peso natal especificado en un diagrama construido sobre los datos del Estudio del Proyecto Colaborativo.