Impact factors and obstetric outcomes of preeclampsia in twin pregnancies by prepregnancy body mass index: a six-year retrospective cohort study

OBJECTIVES

Among many risk factors for preeclampsia (PE), prepregnancy body mass index (BMI) is one of few controllable factors. However, there is a lack of stratified analysis based on the prepregnancy BMI. This study aimed to determine the influencing factors for PE and assess the impact of PE on obstetric outcomes in twin pregnancies by prepregnancy BMI.

METHODS

This was a retrospective cohort study between January 1, 2017, and December 31, 2022, in Southwest China. Impact factors and associations between PE and obstetric outcomes were analyzed separately for twin pregnancies with prepregnancy BMI < 24kg/m2 (non-overweight group) and BMI ≥ 24kg/m2 (overweight group).

RESULTS

In total, 3602 twin pregnancies were included, of which, 672 women were allocated into the overweight group and 11.8% of them reported with PE; 2930 women were allocated into the non-overweight group, with a PE incidence of 5.6%. PE had a negative effect on birthweight and increased the incidence of neonatal intensive care unit admission in both the overweight and non-overweight groups (43.0% vs. 28.0%, p = .008; 45.7% vs. 29.1%, p < .001). Among overweight women, PE increased the proportion of postpartum hemorrhage (15.2% vs. 4.4%, p < .001). After adjustments, multivariate regression analysis showed that excessive gestational weight gain (aOR = 1.103, 95% CI: 1.056-1.152; aOR = 1.094, 95% CI: 1.064-1.126) and hypoproteinemia (aOR = 2.828, 95% CI: 1.501-5.330; aOR = 6.932, 95% CI: 4.819-9.971) were the shared risk factors for PE in both overweight and non-overweight groups. In overweight group, in vitro fertilization was the other risk factor (aOR = 2.713, 95% CI: 1.183-6.878), whereas dichorionic fertilization (aOR = 0.435, 95% CI: 0.193-0.976) and aspirin use during pregnancy (aOR = 0.456, 95% CI: 0.246-0.844) were protective factors. Additionally, anemia during pregnancy (aOR = 1.542, 95% CI: 1.090-2.180) and growth discordance in twins (aOR = 2.451, 95% CI: 1.215-4.205) were connected with an increased risk of PE only in non-overweight twin pregnancies.

CONCLUSIONS

Both discrepancy and similarity of impact factors on developing PE were found between overweight and non-overweight twin pregnancies in this study. However, the dosage and initiation time of aspirin, as well as twin chorionicity on the occurrence of PE in two subgroups, are still debated.

[Prevalence and Trends in Prepregnancy Overweight and Obesity in Northern Iceland 2004-2022]

INTRODUCTION

Prepregnancy overweight and obesity is an increasing public health issue worldwide, including Iceland, and has been associated with higher risk of adverse maternal and birth outcomes. The aim of this study was to investigate trends in prepregnancy weight amongst women in North Iceland from 2004 to 2022, and the prevalence of overweight and obesity in this population.

MATERIAL AND METHODS

This retrospective cross-sectional study included all women who gave birth at Akureyri Hospital in North Iceland between 2004 and 2022 (N = 7410). Information on age, parity, height, and prepregnancy weight was obtained from an electronic labour audit database. Body mass index (BMI) was calculated from self-reported height and weight, and the median BMI and proportions in each of the six BMI categories were calculated for four time periods.

RESULTS

Median BMI increased significantly from 24.5 kg/m2 in 2004-2008 to 26.2 kg/m2 in 2019-2022. On average, BMI increased by 0.15 kg/m2 with each passing year (p<0.001). The prevalence of normal weight decreased from 53% to 40% and the entire BMI distribution shifted towards a higher BMI. The proportion of women in obesity class I (BMI 30.0 - 34.9) increased from 12.8% to 17.3%, the proportion of women in obesity class II (BMI 35.0 - 39.9) doubled (3.7% to 8.1%) and tripled in obesity class III (BMI ≥ 40.0; 1.6% to 4.8%).

CONCLUSION

Prepregnancy weight of women in Northern Iceland has gradually increased over the last 19 years and 30% of pregnant women are now classified as obese. Further studies on the subsequent effects on maternal and birth outcomes are needed, with a focus on strategies to decrease adverse effects and reverse this trend.

Prenatal Weight Change Trajectories and Perinatal Outcomes among Twin Gestations

OBJECTIVE

 Despite an increase in twin pregnancies in recent decades, the Institute of Medicine twin weight gain recommendations remain provisional and provide no guidance for the pattern or timing of weight change. We sought to characterize gestational weight change trajectory patterns and examine associations with birth outcomes in a cohort of twin pregnancies.

STUDY DESIGN

 Prenatal and delivery records were examined for 320 twin pregnancies from a maternal-fetal medicine practice in Austin, TX 2011-2019. Prenatal weights for those with >1 measured weight in the first trimester and ≥3 prenatal weights were included in analyses. Trajectories were estimated to 32 weeks (mean delivery: 33.7 ± 3.3 weeks) using flexible latent class mixed models with low-rank thin-plate splines. Associations between trajectory classes and infant outcomes were analyzed using multivariable Poisson or linear regression.

RESULTS

 Weight change from prepregnancy to delivery was 15.4 ± 6.3 kg for people with an underweight body mass index, 15.4 ± 5.8 kg for healthy weight, 14.7 ± 6.9 kg for overweight, and 12.5 ± 6.4 kg for obesity. Three trajectory classes were identified: low (Class 1), moderate (Class 2), or high gain (Class 3). Class 1 (24.7%) maintained weight for 15 weeks and then gained an estimated 6.6 kg at 32 weeks. Class 2 (60.9%) exhibited steady gain with 13.5 kg predicted total gain, and Class 3 (14.4%) showed rapid gain across pregnancy with 21.3 kg predicted gain. Compared to Class 1, Class 3 was associated with higher birth weight z-score (β = 0.63, 95% confidence interval [CI]: 0.31,0.96), increased risk for large for gestational age (IRR = 5.60, 95% CI: 1.59, 19.67), and birth <32 weeks (IRR = 2.44, 95%CI: 1.10, 5.4) that was attenuated in sensitivity analyses. Class 2 was associated with moderately elevated birth weight z-score (β = 0.24, 95%CI: 0.00, 0.48, p = 0.050).

CONCLUSION

 Gestational weight change followed a low, moderate, or high trajectory; both moderate and high gain patterns were associated with increased infant size outcomes. Optimal patterns of weight change that balance risk during the prenatal, perinatal, and neonatal periods require further investigation, particularly in high-risk twin pregnancies.

KEY POINTS

· A majority gained weight below IOM twin recommendations.. · Three patterns of GWC across pregnancy were identified.. · Moderate or high GWC was associated with infant size..

Higher Than Recommended Folic Acid Intakes is Associated with High Folate Status Throughout Pregnancy in a Prospective French-Canadian Cohort

BACKGROUND

Folate and vitamin B12 status during pregnancy are important for maternal and neonatal health. Maternal intake and prepregnancy body mass index (ppBMI) can influence biomarker status.

OBJECTIVES

This study aimed to, throughout pregnancy; 1) assess folate and B12 status including serum total folate, plasma total vitamin B12, and homocysteine (tHcy); 2) examine how these biomarkers are associated with intakes of folate and B12 and with ppBMI; and 3) determine predictors of serum total folate and plasma total vitamin B12.

METHODS

In each trimester (T1, T2, and T3), food and supplement intakes of 79 French-Canadian pregnant individuals were assessed by 3 dietary recalls (R24W) and a supplement use questionnaire. Fasting blood samples were collected. Serum total folate and plasma total vitamin B12 and tHcy were assessed by immunoassay (Siemens ADVIA Centaur XP).

RESULTS

Participants were 32.1 ± 3.7 y and had a mean ppBMI of 25.7 ± 5.8 kg/m². Serum total folate concentrations were high (>45.3 nmol/L, T1: 75.4 ± 55.1, T2: 69.1 ± 44.8, T3: 72.1 ± 52.1, P = 0.48). Mean plasma total vitamin B12 concentrations were >220 pmol/L (T1: 428 ± 175, T2: 321 ± 116, T3: 336 ± 128, P < 0.0001). Mean tHcy concentrations were <11 μmol/L across trimesters. Most participants (79.6%-86.1%) had a total folic acid intake above the Tolerable Upper Intake Level (UL, >1000 μg/d). Supplement use accounted for 71.9%-76.1% and 35.3%-41.8% of total folic acid and vitamin B12 intakes, respectively. The ppBMI was not correlated with serum total folate (P > 0.1) but was weakly correlated with and predicted lower plasma total vitamin B12 in T3 (r = -0.23, P = 0.04; r² = 0.08, standardized beta [sβ] = -0.24, P = 0.01). Higher folic acid intakes from supplements predicted higher serum total folate (T1: r² = 0.05, sβ = 0.15, P = 0.04, T2: r² = 0.28, sβ = 0.56, P = 0.01, T3: r² = 0.19, sβ = 0.44, P < 0.0001).

CONCLUSIONS

Most pregnant individuals had elevated serum total folate concentrations, reflecting total folic acid intakes above the UL driven by supplement use. Vitamin B12 concentrations were generally adequate and differed by ppBMI and pregnancy stage.

Latent class analysis of placental histopathology: a novel approach to classifying early and late preterm births

BACKGROUND

Neonatal morbidity attributable to prematurity predominantly occurs among early preterm births (<32 weeks) rather than late preterm births (32 to <37 weeks). Methods to distinguish early and late preterm births are lacking given the heterogeneity in pathophysiology and risk factors, including maternal obesity. Although preterm births are often characterized by clinical presentation (spontaneous or clinically indicated), classifying deliveries by placental features detected on histopathology reports may help identify subgroups of preterm births with similar etiology and risk factors. Latent class analysis is an empirical approach to characterize preterm births on the basis of observed combinations of placental features.

OBJECTIVE

To identify histopathologic markers that can distinguish early (<32 weeks) and late preterm births (32 to <37 weeks) that are also associated with maternal obesity and neonatal outcomes.

STUDY DESIGN

Women with a singleton preterm birth at University of Pittsburgh Medical Center Magee-Womens Hospital (Pittsburgh, PA) from 2008 to 2012 and a placental evaluation (89% of preterm births) were stratified into early (n=900, 61% spontaneous) and late preterm births (n=3362, 57% spontaneous). Prepregnancy body mass index was self-reported at first prenatal visit and 16 abstracted placental features were analyzed. Placental subgroups (ie, latent classes) of early and late preterm births were determined separately by latent class analysis of placental features. The optimal number of latent classes was selected by comparing fit statistics. The probability of latent class membership across prepregnancy body mass indexes was estimated in early preterm births and in late preterm births by an extension of multinomial regression called pseudo-class regression, adjusting for race, smoking, education, and parity. The frequencies of severe neonatal morbidity (composite outcome: respiratory distress, bronchopulmonary dysplasia, intraventricular hemorrhage, necrotizing enterocolitis, periventricular leukomalacia, patent ductus arteriosus, and retinopathy of prematurity), small-for-gestational-age, and length of neonatal intensive care unit stay were compared across latent classes by chi-square and Kruskal-Wallis tests.

RESULTS

Early preterm births were grouped into 4 latent classes based on placental histopathologic features: acute inflammation (38% of cases), maternal vascular malperfusion with inflammation (29%), maternal vascular malperfusion (25%), and fetal vascular thrombosis with hemorrhage (8%). As body mass index increased from 20 to 50kg/m², the probability of maternal vascular malperfusion and fetal vascular thrombosis with hemorrhage increased, whereas the probability of maternal vascular malperfusion with inflammation decreased. There was minimal change in the probability of acute inflammation with increasing body mass index. Late preterm births also had 4 latent classes: maternal vascular malperfusion (22%), acute inflammation (12%), fetal vascular thrombosis with hemorrhage (9%), and low-risk pathology (58%). Body mass index was not associated with major changes in likelihood of the latent classes in late preterm births. Associations between body mass index and likelihood of the latent classes were not modified by type of delivery (spontaneous or indicated) in early or late preterm births. Maternal malperfusion and fetal vascular thrombosis with hemorrhage were associated with greater neonatal morbidity than the other latent classes in early and late preterm births.

CONCLUSION

Obesity may predispose women to early but not late preterm birth through placental vascular impairment. Latent class analysis of placental histopathologic data provides an evidence-based approach to group preterm births with shared underlying etiology and risk factors.

[Interaction between Abnormal Prepregnancy Body Mass Index and Hyperlipidemia during Pregnancy on the Risk of Gestational Diabetes Mellitus]

Objective To explore the interaction between abnormal prepregnancy body mass index(pBMI)and high blood lipid level during pregnancy on the risk of gestational diabetes mellitus(GDM). Methods A total of 235 patients with GDM and no blood lipid-related diseases before pregnancy were selected from Hangzhou Women's Hospital during March 2017 to July 2018 as the GDM group.At a ratio of 1∶3,a total of 705 individual age-matched pregnant women with normal glucose metabolism during prenatal examination from the same hospital were selected as the control group.The generalized multifactor dimension reduction(GMDR)method was employed to characterize the possible interaction between pBMI-blood lipid and GDM.The cross-validation consistency,equilibrium test accuracy,and P value were calculated to evaluate the interaction of each model. Results GMDR model analysis showed that the second-order model including pBMI and gestational blood lipid level had the best performance(P=0.001),with the cross-validation consistency of 10/10 and the equilibrium test accuracy of 64.48%,suggesting that there was a potential interaction between pBMI and gestational high blood lipid level.After adjustment of confounding factors,the model demonstrated that overweight/obesity patients with high triglyceride(TG) level had the highest risk of developing GDM(OR=14.349,95%CI=6.449-31.924,P<0.001).Stratified analysis showed that overweight/obesity patients under high TG level group had a higher risk of developing GDM than normal weight individuals(OR=2.243,95%CI=1.173-4.290,P=0.015). Conclusions Abnormal pBMI and high blood lipid level during pregnancy are the risk factors of GDM and have an interaction between each other.Overweight/obese pregnant women with high TG levels are more likely to develop GDM.

A randomized controlled trial of low-dose aspirin for the prevention of preeclampsia in women at high risk in China

BACKGROUND

Low-dose aspirin has been the most widely studied preventive drug for preeclampsia. However, guidelines differ considerably from country to country regarding the prophylactic use of aspirin for preeclampsia. There is limited evidence from large trials to determine the effect of 100 mg of aspirin for preeclampsia screening in women with high-risk pregnancies, based on maternal risk factors, and to guide the use of low-dose aspirin in preeclampsia prevention in China.

OBJECTIVE

The Low-Dose Aspirin in the Prevention of Preeclampsia in China study was designed to evaluate the effect of 100 mg of aspirin in preventing preeclampsia among high-risk pregnant women screened with maternal risk factors in China, where preeclampsia is highly prevalent, and the status of low-dose aspirin supply is commonly suboptimal.

STUDY DESIGN

We conducted a multicenter randomized controlled trial at 13 tertiary hospitals from 11 provinces in China between 2016 and 2019. We assumed that the relative reduction in the incidence of preeclampsia was at least 20%, from 20% in the control group to 16% in the aspirin group. Therefore, the targeted recruitment number was 1000 participants. Women were randomly assigned to the aspirin or control group in a 1:1 allocation ratio. Statistical analyses were performed according to an intention-to-treat basis. The primary outcome was the incidence of preeclampsia, diagnosed along with a systolic blood pressure of ≥140 mm Hg or a diastolic blood pressure of ≥90 mm Hg after 20 weeks of gestation, with a previously normal blood pressure (systolic blood pressure of <140 mm Hg and diastolic blood pressure of <90 mm Hg), and complicated by proteinuria. The secondary outcomes included maternal and neonatal outcomes. Logistic regression analysis was used to determine the significance of difference of preeclampsia incidence between the groups for both the primary and secondary outcomes. Interaction analysis was also performed.

RESULTS

A total of 1000 eligible women were recruited between December 2016 and March 2019, of which the final 898 patients were analyzed (464 participants in the aspirin group, 434 participants in the control group) on an intention-to-treat basis. No significant difference was found in preeclampsia incidence between the aspirin group (16.8% [78/464]) and the control group (17.1% [74/434]; relative risk, 0.986; 95% confidence interval, 0.738-1.317; P=.924). Likewise, adverse maternal and neonatal outcomes did not differ significantly between the 2 groups. Meanwhile, the incidence of postpartum hemorrhage between the 2 groups was similar (6.5% [30/464] in the aspirin group and 5.3% [23/434] in the control group; relative risk, 1.220; 95% confidence interval, 0.720-2.066; P=.459). We did not find any significant differences in preeclampsia incidence between the 2 groups in the subgroup analysis of the different risk factors.

CONCLUSION

A dosage of 100 mg of aspirin per day, initiated from 12 to 20 gestational weeks until 34 weeks of gestation, did not reduce the incidence of preeclampsia in pregnant women with high-risk factors in China.

Associations between prepregnancy body mass index, gestational weight gain and weight catch-up in small-for-gestational-age children

Inadequate gestational weight gain (GWG) was related with a higher incidence of small‐for‐gestational‐age (SGA) births than appropriate GWG; however, the long‐term association of maternal GWG with weight catch‐up growth in SGA children remains unknown. The objective of this study is to evaluate the associations between prepregnancy body mass index (pBMI), GWG and weight catch‐up patterns in SGA children. Data were from the Collaborative Perinatal Project, an American multicentre prospective cohort study. A total of 56,990 gravidas were recruited at the first prenatal visit, and children were followed up until school age. Maternal pBMI, GWG and physical growth of the offspring at birth, 4 months, 1 year, 4 years and 7 years old were recorded. The latent class analysis was employed to form weight catch‐up growth patterns (appropriate, excessive, slow, regression and no catch‐up patterns) in SGA children. SGA children who developed the ‘appropriate catch‐up growth’ pattern and whose mothers had appropriate pBMI and GWG were chosen as the reference. Associations between GWG for different pBMI and weight catch‐up patterns were analysed by multivariate logistic regression models. A total of 1619 infants (9.45%) were born term SGA. After adjusting for relevant confounders, compared with SGA children whose mothers had appropriate pBMI and GWG, SGA children with maternal prepregnancy underweight (for inadequate GWG, GWG below recommendations, adjusted OR: 2.88, 95% CI: 1.13–7.31; for appropriate/excessive GWG, adjusted OR: 3.07, 95% CI: 1.74–5.42) or with prepregnancy normal weight but inadequate GWG (adjusted OR: 2.14, 95% CI: 1.36–3.38) were at a higher risk of having the ‘no catch‐up growth’ pattern. We suggest that SGA children with maternal prepregnancy underweight or inadequate GWG tend to have a poor weight catch‐up growth at least until school age.

Determining optimal gestational weight gain (GWG) in a northwest Chinese population: A CONSORT

ABSTRACT

To determine optimal gestational weight gain (GWG) for the Chinese population.Live singleton deliveries at the largest maternal & childcare hospital in northwest China from 2010 to 2012 were analyzed retrospectively. Multivariable logistic regression analysis was conducted to determine the lowest aggregated risk of interested perinatal outcomes based on Chinese adult body mass index (BMI) categories.Eight thousand eight hundred seventy enrolled parturients were divided into 4 groups according to their prepregnancy BMI: underweight (21.31%, BMI < 18.5 kg/m2), normal weight (67.81%, 18.5 kg/m2 ≤ BMI < 24 kg/m2), overweight (8.99%, 24 kg/m2 ≤ BMI < 28 kg/m2 and obese (1.89%, BMI ≥ 28 kg/m2). The optimal GWG values for the above 4 groups were 16.7 kg (GWG range, 12.0-21.5), 14.5 kg (9.5-19.5), 11.5 kg (7.0-16.5), and 8.0 kg (5.0-13.0). The rates of inadequate, optimal and excessive GWG in present study were 6.14% (545), 62.34% (5529), and 31.52% (2796) respectively, which were significantly different from those of the 2009 Institute of Medicine recommendation (χ2 = 1416.05, Pinteraction < 0.0001).Wider optimal GWG ranges than those recommended by Institute of Medicine were found in our study, and our proposed criteria seems to be practical to the Chinese population.

Association between maternal prepregnancy body mass index and risk of preterm birth in more than 1 million Asian American mothers

BACKGROUND

Asian Americans are among the fastest growing subpopulations in the United States. However, evidence about maternal prepregnancy body mass index (BMI) and preterm birth among Asian Americans is lacking.

METHODS

This population-based study used nationwide birth certificate data from the US National Vital Statistics System 2014 to 2018. All Asian American mothers who had a singleton live birth were included. According to Asian-specific cutoffs, maternal prepregnancy BMI was classified into underweight (BMI < 18.5 kg/m2 ), normal weight (BMI 18.5-22.9 kg/m2 ), overweight (BMI 23.0-27.4 kg/m2 ), class I obesity (BMI 27.5-32.4 kg/m2 ), class II obesity (BMI 32.5-37.4 kg/m2 ), and class III obesity (BMI ≥37.5 kg/m2 ). Preterm birth was defined as gestational age less than 37 weeks. Multivariable logistic regression models were used to estimate the odds ratio (OR) of preterm birth.

RESULTS

We included 1 081 341 Asian American mother-infant pairs. The rate of preterm birth was 6.51% (n = 70 434). The rate of maternal prepregnancy overweight and obesity was 46.80% (n = 506 042). Compared with mothers with normal weight, the adjusted OR of preterm delivery was 1.04 (95% CI, 1.01-1.07) for underweight mothers, 1.18 (95% CI, 1.16-1.20) for overweight mothers, 1.41 (95% CI, 1.37-1.44) for mothers with class I obesity, 1.69 (95% CI, 1.63-1.76) for mothers with class II obesity, and 1.78 (95% CI, 1.66-1.90) for mothers with class III obesity. Similar patterns of associations were observed in Asian American mothers across different country origins.

CONCLUSIONS

Among Asian American mothers, maternal prepregnancy overweight or obesity, defined by Asian-specific, lower BMI cutoffs, was significantly associated with an increased risk of preterm birth. The risk of preterm birth increased with increasing obesity severity. These findings highlight the importance of using Asian-specific BMI cutoffs in assessing risk of preterm birth among Asian American mothers.

Impaired fetal growth in mothers with inadequate gestational weight gain: a retrospective study in Japanese uncomplicated pregnancy

Introduction: The average birth weight in Japan has gradually decreased and the number of low birth weight infant has increased over the last 30 years. Japanese pregnant women are characterized with lower prevalence of obesity than those in other developed countries, and maternal underweight before pregnancy is independently associated with low birth weight. However, the association between maternal inadequate gestational weight gain (GWG) and the risk of small for gestational age (SGA) in Japanese uncomplicated pregnant women has not been fully understood. This study aimed to examine the effect of maternal inadequate GWG on the risk of SGA in Japanese uncomplicated pregnancies.Methods: We retrospectively analyzed uncomplicated Japanese singleton pregnancies that delivered at term gestation in our institution from 2006 to 2016. The association between GWG and birth weight was analyzed by multiple linear regression. Potential confounding factors included maternal age, parity, prepregnancy BMI, and neonatal sex. The association between inadequate GWG and SGA was also examined by logistic regression.Results: A total of 3837 mother-neonate dyads were analyzed. Maternal GWG was 10.1 ± 3.7 kg (mean ± SD), and 2529 (66%) had inadequate GWG. After adjusting for confounding factors, GWG significantly correlated with birth weight (standardized β  =  0.199, p < .001). Inadequate GWG increased the risk of delivering SGA neonate (adjusted odds ratio (aOR) = 1.97 [1.45-2.68], p < .001). This association was particularly pronounced in underweight (aOR = 2.95 [1.38-6.29], p = .005) and normal weight mothers (aOR = 1.79 [1.27-2.52], p = .001), and not in overweight/obese mothers (p = .115).Conclusion: Maternal GWG is associated with birth weight in Japanese women with uncomplicated singleton pregnancies. Inadequate GWG is an important risk factor of SGA, particularly in non-obese women. The present finding would potentially provide further evidence that promoting adequate gestational weight gain in Japanese underweight and normal weight mothers would reduce SGA, as well as metabolic dysfunction in later life.

The Impact of Prepregnancy Body Mass Index and Gestational Weight Gain on Perinatal Outcomes for Women With Gestational Diabetes Mellitus

BACKGROUND

Gestational diabetes mellitus (GDM), an obstetric disease that affects the health of pregnant women, is one of the key factors associated with perinatal mortality or disease.

AIMS

To explore the impact of prepregnancy body mass index (BMI) and gestational weight gain (GWG) on perinatal outcomes for women with GDM.

METHODS

With a retrospective study design, women were recruited who received prenatal checkups, gave birth at two teaching hospitals in southern Taiwan from 1995 to 2011, and received a diagnosis of GDM by an obstetrician. A trained research assistant collected the participants' data in each hospital's archives room. The researcher used a retrospective case study method to identify women who received a GDM diagnosis between 1995 and 2011.

RESULTS

Women with GDM and with an overweight prepregnancy BMI were more likely to have cesarean deliveries and to use glucose-lowering medicines after delivery. Their newborns also had a higher birth weight. In addition, gestational hypertension and cesarean delivery were more common in women with GDM and with excessive GWG than in women with GDM and with normal GWG. The newborns of women with GDM and with excessive GWG had higher birth weights and more nuchal cord than those of women with GDM and with normal GWG. More women with GDM and with excessive GWG underwent blood glucose monitoring than did women with GDM and with normal GWG.

LINKING EVIDENCE TO ACTION

The prepregnancy weight and GWG significantly affected perinatal outcomes in both the women with GDM themselves and their newborns. Healthcare professionals must provide childbearing women with additional health education in the areas of health promotion, nutrition, weight control, exercise, and maintaining regular everyday lives.

Prospective association of fetal liver blood flow at 30 weeks gestation with newborn adiposity

BACKGROUND

The production of variation in adipose tissue accretion represents a key fetal adaptation to energy substrate availability during gestation. Because umbilical venous blood transports nutrient substrate from the maternal to the fetal compartment and because the fetal liver is the primary organ in which nutrient interconversion occurs, it has been proposed that variations in the relative distribution of umbilical venous blood flow shunting either through ductus venosus or perfusing the fetal liver represents a mechanism underlying this adaptation.

OBJECTIVE

The objective of the present study was to determine whether fetal liver blood flow assessed before the period of maximal fetal fat deposition (ie, the third trimester of gestation) is prospectively associated with newborn adiposity.

STUDY DESIGN

A prospective study was conducted in a cohort of 62 uncomplicated singleton pregnancies. Fetal ultrasonography was performed at 30 weeks gestation for conventional fetal biometry and characterization of fetal liver blood flow (quantified by subtracting ductus venosus flow from umbilical vein flow). Newborn body fat percentage was quantified by dual energy X-ray absorptiometry imaging at 25.8 ± 3.3 (mean ± standard error of the mean) postnatal days. Multiple regression analysis was used to determine the proportion of variation in newborn body fat percentage explained by fetal liver blood flow. Potential confounding factors included maternal age, parity, prepregnancy body mass index, gestational weight gain, gestational age at birth, infant sex, postnatal age at dual energy X-ray absorptiometry scan, and mode of infant feeding.

RESULTS

Newborn body fat percentage was 13.5% ± 2.4% (mean ± standard error of the mean). Fetal liver blood flow at 30 weeks gestation was significantly and positively associated with newborn total fat mass (r=0.397; P<.001) and body fat percentage (r=0.369; P=.004), but not with lean mass (r=0.100; P=.441). After accounting for the effects of covariates, fetal liver blood flow explained 13.5% of the variance in newborn fat mass. The magnitude of this association was pronounced particularly in nonoverweight/nonobese mothers (prepregnancy body mass index, <25 kg/m²; n=36) in whom fetal liver blood flow explained 24.4% of the variation in newborn body fat percentage.

CONCLUSION

Fetal liver blood flow at the beginning of the third trimester of gestation is associated positively with newborn adiposity, particularly among nonoverweight/nonobese mothers. This finding supports the role of fetal liver blood flow as a putative fetal adaptation underlying variation in adipose tissue accretion.

Prepregnancy body mass index in a first uncomplicated pregnancy and outcomes of a second pregnancy

OBJECTIVE

This study examined the effect of body mass index (BMI) before a first uncomplicated pregnancy on maternal and fetal outcomes in a subsequent pregnancy, including preterm births, preeclampsia, cesarean delivery, small for gestational age, large for gestational age, and neonatal deaths.

STUDY DESIGN

We conducted a population-based cohort study (n = 121,092) using the Missouri maternally linked birth registry (1989 through 2005). Multivariable binary logistic regression models were fit to estimate odds ratios and 95% confidence intervals for the parameters of interest after controlling for sociodemographic and pregnancy-related confounders in the second pregnancy.

RESULTS

Compared to women with a normal BMI in their first pregnancy, those who were underweight prepregnancy had increased odds for preterm birth by 20% and small for gestational age by 40% in their second pregnancy, while those with prepregnancy obesity had increased odds for large for gestational age, preeclampsia, cesarean delivery, and neonatal deaths in their second pregnancy by 54%, 156%, 85%, and 37%, respectively.

CONCLUSION

Women starting a first pregnancy with suboptimal BMI may be at risk of adverse maternal and fetal outcomes in a subsequent pregnancy, even if their first pregnancy was uncomplicated or if they reached a normal weight by their second pregnancy. The long-term consequences of suboptimal BMI carry considerable public health implications.

Trends in gestational weight gain: the Pregnancy Risk Assessment Monitoring System, 2000-2009

OBJECTIVE

Achieving adequate gestational weight gain (GWG) is important for optimal health of the infant and mother. We estimate current population-based trends of GWG.

STUDY DESIGN

We analyzed data from the Pregnancy Risk Assessment Monitoring System for 124,348 women who delivered live infants in 14 states during 2000 through 2009. We examined prevalence and trends in GWG in pounds as a continuous variable, and within 1990 Institute of Medicine (IOM) recommendations (yes/no) as a dichotomous variable. We examined adjusted trends in mean GWG using multivariable linear regression and GWG within recommendations using multivariable multinomial logistic regression.

RESULTS

During 2000 through 2009, 35.8% of women gained within IOM GWG recommendations, 44.4% gained above, and 19.8% gained below. From 2000 through 2009, there was a biennial 1.0 percentage point decrease in women gaining within IOM GWG recommendations (P trend < .01) and a biennial 0.8 percentage point increase in women gaining above IOM recommendations (P trend < .01). The percentage of women gaining weight below IOM recommendations remained relatively constant from 2000 through 2009 (P trend = .14). The adjusted odds of gaining within IOM recommendations were lower in 2006 through 2007 (adjusted odds ratio, 0.90; 95% confidence interval, 0.85-0.96) and 2008 through 2009 (adjusted odds ratio, 0.90; 95% confidence interval, 0.85-0.96) relative to 2000 through 2001.

CONCLUSION

Overall, from 2000 through 2009 the percentage of women gaining within IOM recommendations slightly decreased while mean GWG slightly increased. Efforts are needed to develop and implement strategies to ensure that women achieve GWG within recommendations.

C-reactive protein and preterm delivery: clues from placental findings and maternal weight

To study the association between maternal C-reactive protein (CRP) and preterm delivery (PTD) pathways, CRP was measured in maternal plasma collected at mid-pregnancy (n = 1310). PTD was subdivided into spontaneous (sPTD) or medically indicated (MI-PTD). Histologic chorioamnionitis (HCA) was determined by placental histopathology (n = 1076). Adjusted CRP levels were elevated for sPTD (5.5 µg/mL) versus term deliveries (4.8 µg/mL) and higher in sPTD with HCA (6.3 µg/mL). After removing HCA, an interaction between body mass index (BMI) and sPTD in relation to CRP was noted. In BMI-stratified models, an association between CRP and sPTD among women with prepregnancy BMI >25 (8.9 µg/mL for sPTD; 7.2 µg/mL for term) was absent among women with lower BMI. We propose that this remaining association in overweight/obese women suggests that CRP may mark an obesity/inflammation PTD pathway that is distinct from the pathway indicated by HCA.