Phthalate and phthalate replacement concentrations in relationship to adiposity in a multi-racial cohort of children.

BACKGROUND/OBJECTIVE: Phthalates and phthalate replacements are used in multiple everyday products, making many of them bioavailable to children. Experimental studies suggest that phthalates and their replacements may be obesogenic, however, epidemiologic studies remain inconsistent. Therefore, our objective was to examine the association between phthalates, phthalate replacements and childhood adiposity/obesity markers in children. SUBJECTS/METHODS: A cross-sectional study was conducted in 630 racial/ethnically diverse children ages 4-8 years. Urinary oxidative metabolites of DINCH and DEHTP, three low molecular weight (LMW) phthalates, and eleven high molecular weight (HMW) phthalates were measured. Weight, height, waist circumference and % body fat were measured. Composite molar sum groups (nmol/ml) were natural log-transformed. Linear regression models adjusted for urine specific gravity, sex, age, race-ethnicity, birthweight, breastfeeding, reported activity level, mother's education and pre-pregnancy BMI. RESULTS: All children had LMW and HMW phthalate metabolites and 88% had DINCH levels above the limit of detection. One unit higher in the log of DINCH was associated with 0.106 units lower BMI z-score [ß = -0.106 (95% CI: -0.181, -0.031)], 0.119 units lower waist circumference z-score [ß = -0.119 (95% CI: -0.189, -0.050)], and 0.012 units lower percent body fat [ß = -0.012 (95% CI: -0.019, -0.005)]. LMW and HMW group values were not associated with adiposity/obesity. CONCLUSIONS: We report an inverse association between child urinary DINCH levels, a non-phthalate plasticizer that has replaced DEHP in several applications, and BMI z-score, waist circumference z-score and % body fat in children. Few prior studies of phthalates and their replacements in children have been conducted in diverse populations. Moreover, DINCH has not received a great deal of attention or regulation, but it is a common exposure. In summary, understanding the ubiquitous nature of these chemical exposures and ultimately their sources will contribute to our understanding of their relationship with obesity.

Multiethnic Growth Standards for Fetal Body Composition and Organ Volumes Derived from 3D Ultrasonography.

BACKGROUND: A major goal of contemporary obstetrical practice is to optimize fetal growth and development throughout pregnancy. To date, fetal growth during prenatal care is assessed by performing ultrasonographic measurement of two-dimensional fetal biometry to calculate an estimated fetal weight. Our group previously established two-dimensional fetal growth standards using sonographic data from a large cohort with multiple sonograms. A separate objective of that investigation involved the collection of fetal volumes from the same cohort. OBJECTIVE: The Fetal 3D Study was designed to establish standards for fetal soft tissue and organ volume measurements by three-dimensional ultrasonography and compare growth trajectories with conventional two-dimensional measures where applicable. STUDY DESIGN: The NICHD Fetal 3D Study included research-quality images of singletons collected in a prospective, racially and ethnically diverse, low-risk cohort of pregnant individuals at 12 U.S. sites, with up to five scans per fetus (N=1,730 fetuses). Abdominal subcutaneous tissue thickness was measured from two-dimensional images and fetal limb soft tissue parameters extracted from three-dimensional multiplanar views. Cerebellar, lung, liver and kidney volumes were measured using virtual organ computer aided analysis (VOCAL). Fractional arm and thigh total volumes, and fractional lean limb volumes were measured, with fractional limb fat volume calculated by subtracting lean from total. For each measure, weighted curves (5th, 50th, 95th percentiles) were derived from 15-41 weeks' using linear mixed models for repeated measures with cubic splines. RESULTS: Subcutaneous thickness of the abdomen, arm, and thigh increased linearly, with slight acceleration around 27-29 weeks. Fractional volumes of the arm, thigh, and lean limb volumes increased along a quadratic curvature, with acceleration around 29-30 weeks. In contrast, growth patterns for two-dimensional humerus and femur lengths demonstrated a logarithmic shape, with fastest growth in the 2nd trimester. The mid-arm area curve was similar in shape to fractional arm volume, with an acceleration around 30 weeks, whereas the curve for the lean arm area was more gradual. The abdominal area curve was similar to the mid-arm area curve with an acceleration around 29 weeks. The mid-thigh and lean area curves differed from the arm areas by exhibiting a deceleration at 39 weeks. The growth curves for the mid arm and thigh circumferences were more linear with some decelerations. Cerebellar two-dimensional diameter increased linearly, whereas cerebellar three-dimensional volume growth gradually accelerated until 32 weeks and then decelerated. Lung, kidney, and liver volumes all demonstrated gradual early growth followed by a linear acceleration beginning at 25 weeks for lungs, 26-27 weeks for kidneys, and 29 weeks for liver. CONCLUSION: Growth patterns and timing of maximal growth for three-dimensional lean and fat measures, limb and organ volumes differed from patterns revealed by traditional two-dimensional growth measures, suggesting these parameters reflect unique facets of fetal growth. Growth in these three-dimensional measures may be altered by genetic, nutritional, metabolic or environmental influences and pregnancy complications, in ways not identifiable using corresponding two-dimensional measures. Further investigation into the relationships of these three-dimensional standards to abnormal fetal growth, adverse perinatal outcomes, and health status in postnatal life is warranted.

Spontaneous skull base cerebrospinal fluid leak during pregnancy: a case report and review of the literature.

BACKGROUND: Idiopathic intracranial hypertension can lead to dural defects and spontaneous leakage of cerebrospinal fluid (CSF) from the skull base. Skull base CSF leaks are rarely reported in pregnancy but pose unique challenges for obstetricians and anesthesiologists. CASE PRESENTATION: A 31-year-old G4P1021 at 14 weeks developed debilitating headaches and CSF rhinorrhea. Brain imaging revealed a bony defect of the sphenoid sinus with a meningoencephalocele and a partially empty sella, consistent with CSF leakage from a skull base defect. The patient was neurologically stable without signs of meningitis; thus, management was focused on symptomatic alleviation. A planned cesarean section was performed at 38 weeks under spinal anesthesia. The patient had spontaneous marked improvement of her symptoms postpartum. CONCLUSION: Pregnancy may exacerbate skull base CSF leaks, requiring careful management with a multidisciplinary team. Neuraxial anesthesia can safely be performed in pregnant individuals with spontaneous skull base CSF leakage, but further studies are needed to determine the safest mode of delivery in these patients.

Associations of Maternal Prenatal Stress and Depressive Symptoms With Childhood Neurobehavioral Outcomes in the ECHO Cohort of the NICHD Fetal Growth Studies: Fetal Growth Velocity as a Potential Mediator.

OBJECTIVE: Maternal prenatal stress and mood symptoms are associated with risk for child psychopathology. Within the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies (ECHO-FGS), a racially and ethnically diverse cohort, we studied associations between prenatal stress and depressive symptoms with child neurobehavior, and potential mediation by fetal growth velocity (FGV) in low-risk pregnancies. METHOD: For 730 mother-child pairs, we had serial ultrasound measurements, self-reports of prenatal stress and depression, observations of child executive functions and motor skills from 4 to 8 years, and maternal reports of child psychiatric problems. We tested associations between prenatal stress and depressive symptoms with child neurobehavior in regression analyses, and associations with FGV in mixed effect models. Post hoc we tested severity of prenatal symptoms; FGV at 25th, 50th, and 75th percentiles; and moderation by biological sex and by race and ethnicity. RESULTS: Prenatal stress and depressive symptoms were associated with child psychiatric problems, and prenatal depressive symptoms with decrements in executive functions and motor skills, especially in biological male children. Neither prenatal stress nor depressive symptoms were associated with FGV. CONCLUSION: In one of the largest cohorts with observed child outcomes, and the first with broad representation of race and ethnicity in the United States, we found that prenatal stress and depressive symptoms were associated with greater reports of child psychiatric symptoms. Only prenatal depressive symptoms were associated with observed decrements in cognitive abilities, most significantly in biological male children. Stress during low-risk pregnancies may be less detrimental than theorized. There was no mediation by FGV. These findings support the need to attend to even small changes in prenatal distress, as these may have long-lasting implications.

The association between maternal pre-pregnancy BMI, gestational weight gain and child adiposity: A racial-ethnically diverse cohort of children.

BACKGROUND: The prevalence of obesity in US children has more than tripled in the past 40 years; hence, it is critical to identify potentially modifiable factors that may mitigate the risk. OBJECTIVES: To examine the association between maternal pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and child adiposity as measured by BMI, waist circumference and percent body fat in a racial-ethnically diverse cohort. METHODS: In a prospective cohort study of healthy women without chronic disease, we examined the association between pre-pregnancy BMI, GWG and child adiposity. Children ages 4-8 years (n = 816) in the Environmental Influences on Child Health Outcomes-NICHD Fetal Growth Studies were assessed. Trained study staff ascertained maternal pre-pregnancy BMI, GWG and child adiposity. RESULTS: The odds of child obesity (≥95th BMI percentile) increased independently for each unit increase in maternal pre-pregnancy BMI [OR = 1.12 (95% CI: 1.08, 1.17)] and for each 5-kg increase in GWG [OR = 1.25 (95% CI: 1.07, 1.47)]. The odds of child waist circumference (≥85th percentile) also increased independently for pre-pregnancy BMI [OR = 1.09 (95% CI: 1.05, 1.12)] and GWG [OR = 1.18 (95% CI: 1.04, 1.34)]. CONCLUSIONS: Maternal pre-pregnancy BMI and GWG were each independently and positively associated with child obesity and high child waist circumference.

Early Exposure to Animals and Childhood Body Mass Index Percentile and Percentage Fat Mass.

INTRODUCTION: A few studies have identified childhood animal exposure as associated with adiposity, but results are inconsistent and differ in timing. METHODS: We conducted an observational cohort study of children ages 4-8 in the Environmental Influences on Child Health Outcomes [ECHO] study. The main exposure was having a dog in the home and/or regular contact with farm animals during the first year of life. Outcomes of interest were child BMI percentile (adjusted for gender and age) categorized as normal/underweight (<85th percentile), overweight (85th to <95th), and obese (≥95th), and percent fat mass (continuous). Associations were analyzed using multinomial logistic regression and multivariable linear regression, respectively, with and without multiple imputation. RESULTS: First year animal exposure occurred in 245 of 770 (31.8%) children. Children with early animal exposure had 0.53 (95% CI: 0.28, 0.997) times the odds of being in the obese BMI category compared to those exposed to animals after controlling for covariates: maternal pre-pregnancy BMI, race/ethnicity, reported child activity level, receiving food assistance, age child began daycare (<1 year vs 1+), exclusively breastfed x6 months, and NICU admission (n=721). Children with early animal exposure had, on average, 1.5% (95% CI: -3.0, -0.1) less fat mass than exposed children after adjustment for maternal BMI, race/ethnicity, activity, food assistance, breastfeeding, and maternal education (n=548). Multiple imputation did not alter either result. CONCLUSION: These results provide evidence that exposure to dogs or farm animals in the first year of life is associated with lower odds of obesity and lower percent fat mass in childhood.

Breastfeeding Associations with Childhood Obesity and Body Composition: Findings from a Racially Diverse Maternal-Child Cohort.

Background: Studies suggest breastfeeding lowers obesity risk in childhood, but generalizability of existing evidence is limited. We examined associations of breastfeeding with childhood overweight, obesity, and percentage body fat, in a racially diverse maternal-child cohort. Methods: This cross-sectional study included 823 children, ages 4-8 years, enrolled in the Environmental Exposures and Child Health Outcomes (ECHO) cohort, a subset of the National Institute of Child Health and Human Development Fetal Growth Studies cohort. Logistic regression was used to estimate odds ratios and 95% confidence intervals (CIs) for overweight [BMI (kg/m2) 85th to <95th percentile] and obesity (BMI ≥95th percentile) in relation to breastfeeding including duration of exclusive and total breastfeeding. Linear regression was used to evaluate association between breastfeeding and percentage body fat measured by bioelectrical impedance analysis. Results: Fifty-two percent of children were male, 32% non-Hispanic Black, 29% Hispanic, 27% non-Hispanic White, and 13% Asian; 16% were overweight and 13% obese. Six months of exclusive breastfeeding, compared with no breastfeeding, was associated with 60% lower odds of obesity (95% CI 0.18-0.91) adjusting for age, gender, race, socioeconomic status, maternal BMI, and child's activity. Percentage body fat was inversely associated with breastfeeding duration. For none, <6, and ≥6 months of exclusive breastfeeding, adjusted mean percentage body fat was 16.8, 14.5, and 13.4, respectively. Results did not differ by gender, race/ethnicity, or maternal BMI status. Conclusions: Exclusive breastfeeding for the first 6 months of life is inversely and significantly associated with obesity and percentage body fat at ages 4-8 years. These findings support current breastfeeding guidelines.

Complicated placenta accreta spectrum: identifying a high-risk cohort.

OBJECTIVE: To assess differences in the perioperative complication rate between patients with placenta accreta spectrum (PAS) with and without complicating factors. METHODS: This retrospective cohort study included subjects who underwent cesarean hysterectomy with histology-proven PAS between 23 0/7 and 42 0/7 weeks gestational age (GA) from 1 July 2008 to 11 April 2017. Perioperative outcomes were compared between those with uncomplicated PAS and "complicated PAS," defined as PAS subjects who experienced ≥2 bleeding episodes, preterm premature rupture of membranes (PPROM), or premature contractions requiring tocolysis. RESULTS: Overall, 26 complicated PAS and 27 uncomplicated PAS cases were compared; no difference in the rate of perioperative complications was identified. An increased proportion of complicated PAS cases required blood product transfusion before delivery: 2 (40%), 3 (27.3%), and 2 patients (20%) for those with PPROM, preterm contractions, and ≥2 bleeding episodes respectively, compared to patients with uncomplicated PAS, having no transfusions (p = .001). Time of delivery was earlier for patients with complicated compared to uncomplicated PAS (median GA 30.9 [Q1 = 27.9; Q3 = 31.9] and 34.9 [Q1 = 32.1; Q3 = 35.7], p < .001). Median birthweights were lower (p < .0144) and maternal length of stay longer (p < .0012) for complicated PAS. CONCLUSION: Patients with complicated PAS were not at higher risk for perioperative complications but were associated with earlier delivery, required more antenatal blood transfusions, and had a longer LOS.

Massive unilateral fetal axillary lymphangioma: A case report.

We report a substantial axillary lymphangioma in a fetus delivered at 38 weeks of gestation. Detailed fetal survey at 20 weeks revealed a 5.45 × 3.72 cm nonvascular cystic axillary structure without other malformations; amniocentesis was negative. Serial surveillance was performed throughout the pregnancy. A male infant weighing 3000 g with a 16 × 12 × 9 cm septated cystic mass arising from the left axilla was delivered via cesarean section. The newborn period was complicated by cellulitis overlying the mass and interval cystic hemorrhage requiring sclerotherapy and subsequent excision. Nonnuchal lymphangiomas may be etiologically distinct entities. The prognostic factors include anatomic location, presence of septa, and association with other congenital abnormalities. A thorough evaluation, multidisciplinary approach, and close surveillance should be undertaken to optimize neonatal outcomes.

Nutrition during Pregnancy: Findings from the National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singleton Cohort.

BACKGROUND: Accumulating evidence indicates that maternal diets are important for optimizing maternal and offspring health. Existing research lacks comprehensive profiles of maternal diets throughout pregnancy, especially in a racially/ethnically diverse obstetrical population. OBJECTIVE: The aim was to characterize diets in a longitudinal US pregnancy cohort by trimester, race/ethnicity, and prepregnancy BMI. METHODS: Data were obtained from pregnant women in the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singleton cohort (2009-2013). A food-frequency questionnaire (FFQ) at 8-13 wk of gestation assessed periconception and first-trimester diet (n = 1615). Automated, self-administered, 24-h dietary recalls targeted at 16-22, 24-29, 30-33, and 34-37 wk of gestation assessed second- and third-trimester diets (n = 1817 women/6791 recalls). The Healthy Eating Index-2010 (HEI-2010) assessed diet quality (i.e., adherence to US Dietary Guidelines). Variations in weighted energy-adjusted means for foods and nutrients were examined by trimester, self-identified race/ethnicity, and self-reported prepregnancy BMI. RESULTS: Mean (95% CI) HEI-2010 was 65.9 (64.9, 67.0) during periconception to the first trimester assessed with an FFQ and 51.6 (50.8, 52.4) and 51.5 (50.7, 52.3) during the second trimester and third trimester, respectively, assessed using 24-h recalls. No significant differences were observed between the second and third trimester in macronutrients, micronutrients, foods, or HEI-2010 components (P ≥ 0.05). Periconception to first-trimester HEI-2010 was highest among Asian/Pacific Islander [67.2 (65.9, 68.6)] and lowest among non-Hispanic Black [58.7 (57.5, 60.0)] women and highest among women with normal weight [67.2 (66.1, 68.4)] and lowest among women with obesity [63.5 (62.1, 64.9)]. Similar rankings were observed in the second/third trimesters. CONCLUSIONS: Most pregnant women in this cohort reported dietary intakes that, on average, did not meet US Dietary Guidelines for nonpregnant individuals. Also, diet differed across race/ethnic groups and by prepregnancy BMI, with the lowest overall dietary quality in all trimesters among non-Hispanic Black women and women with obesity. No meaningful changes in dietary intake were observed between the second and third trimesters.

Ibuprofen and Postpartum Blood Pressure in Women With Hypertensive Disorders of Pregnancy: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the effect of ibuprofen on blood pressure in women with a diagnosis of hypertensive disorders of pregnancy and mild hypertension during the immediate postpartum period. METHODS: In this double-blind controlled trial, we randomly assigned women with a diagnosis of hypertensive disorders of pregnancy and mild hypertension to receive a postpartum analgesic regimen with either ibuprofen or acetaminophen. The primary outcome was average mean arterial pressure during the postpartum hospital stay. Prespecified secondary outcomes included use of breakthrough opioid pain medications, length of hospital stay, and postpartum diuresis, defined as urine output of at least 200 mL/hour for 4 hours. A sample size of 56 participants was needed to detect a difference of 6 mm Hg in average mean arterial pressure between the study groups. RESULTS: From January 17, 2017, to February 24, 2018, 61 participants were randomized and completed the trial, 31 participants in the ibuprofen group and 30 in the control group. Baseline characteristics were similar between groups. Postpartum average arterial pressure did not differ between study groups (93±8 mm Hg for those in the ibuprofen group vs 93±7 mm Hg in the control group, P=.93). Breakthrough opioid medications were requested by 24% of the participants in the ibuprofen group compared with 30% in the control group (P=.62). The ibuprofen group did not have a longer length of stay (48 hours vs 43 hours in the control group) or decreased rate of postpartum diuresis (61% in ibuprofen group vs 77% in the control group, P=.2). CONCLUSION: In women with hypertensive disorders of pregnancy and mild hypertension, ibuprofen did not increase postpartum blood pressure compared with women not receiving nonsteroidal antiinflammatory drugs. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT03011567.

Fetal growth patterns in pregnancy-associated hypertensive disorders: NICHD Fetal Growth Studies.

BACKGROUND: Fetal growth patterns in pregnancy-associated hypertensive disorders is poorly understood because prospective longitudinal data are lacking. OBJECTIVE: The objective of the study was to compare longitudinal fetal growth trajectories between normotensive women and those with pregnancy-associated hypertensive disorders. STUDY DESIGN: This is a study based on data from a prospective longitudinal cohort study of fetal growth performed at 12 US sites (2009-2013). Project gestational age was confirmed by ultrasound between 8 weeks 0 days and 13 weels 6 days, and up to 6 ultrasounds were performed across gestation. Hypertensive disorders were diagnosed based on 2002 American College of Obstetricians and Gynecologists guidelines and grouped hierarchically as severe preeclampsia (including eclampsia or HELLP [hemolysis, elevated liver enzymes, and low platelet count] syndrome), mild preeclampsia, severe gestational hypertension, mild gestational hypertension, or unspecified hypertension. Women without any hypertensive disorder constituted the normotensive group. Growth curves for estimated fetal weight and individual biometric parameters including biparietal diameter, head circumference, abdominal circumference, and femur and humerus length were calculated for each group using linear mixed models with cubic splines. Global and weekly pairwise comparisons were performed between women with a hypertensive disorder compared with normotensive women to analyze differences while adjusting for confounding variables. Delivery gestational age and birthweights were compared among groups. RESULTS: Of 2462 women analyzed, 2296 (93.3%) were normotensive, 63 (2.6%) had mild gestational hypertension, 54 (2.2%) mild preeclampsia, 32 (1.3%) severe preeclampsia, and 17 (0.7%) unspecified hypertension. Compared with normotensive women, those with severe preeclampsia had estimated fetal weights that were reduced between 22 and 38 weeks (all weekly pairwise values of P < .008). Women with severe preeclampsia compared with those without hypertension also had significantly smaller fetal abdominal circumference between 23-31 and 33-37 weeks' gestation (weekly pairwise values of P < .04). Scattered weekly growth differences were noted on other biometric parameters between these 2 groups. The consistent differences in estimated fetal weight and abdominal circumference were not observed between women with other hypertensive disorders and those who were normotensive. Women with severe preeclampsia delivered significantly earlier (mean gestational age 35.9 ± 3.2 weeks) than the other groups (global P < .0001). Birthweights in the severe preeclampsia group were also significantly lower (mean -949.5 g [95% confidence interval, -1117.7 to -781.2 g]; P < .0001) than in the normotensive group. CONCLUSION: Among women with pregnancy-associated hypertensive disorders, only those destined to develop severe preeclampsia demonstrated a significant and consistent difference in fetal growth (ie, smaller estimated fetal weight and abdominal circumference) when compared with normotensive women.

Disparate Rates of Cesarean Delivery in Term Nulliparous Women with Hypertensive Disorders of Pregnancy.

OBJECTIVE: To evaluate the prevalence of cesarean delivery in women with hypertensive disorders of pregnancy (HDP), and explore whether maternal, sociodemographic, or obstetric comorbidities contribute to cesarean delivery rates. STUDY DESIGN: This is a retrospective cohort study of nulliparous, term, singleton, vertex women using the 2013 U.S. National Vital Statistics Report. We compared prevalence of risk factors for cesarean delivery between women with and without HDP, and then calculated probabilities of cesarean delivery after controlling for these risk factors. RESULTS: In this cohort of 1,439,977 women, the unadjusted probability of cesarean delivery in women with HDP was 39.5 versus 26.8% in those without the diagnosis (p < 0.01). Hypertensive women had more risk factors for cesarean delivery, most notably morbid obesity (9.0 vs. 3.1%, p < 0.01), diabetes (9.9 vs. 4.4%, p < 0.01), and induction of labor (59.2 vs. 26.9%, p < 0.01). Despite this, after controlling for these risk factors, hypertensive women remained significantly more likely to undergo cesarean delivery (35.1 vs. 26.4%, p < 0.01). CONCLUSION: Even after controlling for multiple comorbidities, hypertension remained a significant risk factor for cesarean delivery in nulliparous women at term. Hypertensive women may therefore represent an important target population in efforts aimed at reduction of cesarean rates.

The Utilization of Interventional Radiologic Procedures in the Surgical Management of Placenta Accreta Syndrome.

The role of Interventional radiologic procedures for the management of suspected placenta accreta spectrum (PAS) has evolved considerably over last 3 decades. In this article, the authors describe the various techniques of vascular occlusion for the management of PAS and provide a brief review of the literature examining the pros and cons in the use of these devices.

Fetal growth velocity: the NICHD fetal growth studies.

BACKGROUND: Accurately identifying pregnancies with accelerated or diminished fetal growth is challenging and generally based on cross-sectional percentile estimates of fetal weight. Longitudinal growth velocity might improve identification of abnormally grown fetuses. OBJECTIVE: We sought to complement fetal size standards with fetal growth velocity, develop a model to compute fetal growth velocity percentiles for any given set of gestational week intervals, and determine association between fetal growth velocity and birthweight. STUDY DESIGN: This was a prospective cohort study with data collected at 12 US sites (2009 through 2013) from 1733 nonobese, low-risk pregnancies included in the singleton standard. Following a standardized sonogram at 10w0d-13w6d, each woman was randomized to 1 of 4 follow-up visit schedules with 5 additional study sonograms (targeted ranges: 16-22, 24-29, 30-33, 34-37, and 38-41 weeks). Study visits could occur ± 1 week from the targeted GA. Ultrasound biometric measurements included biparietal diameter, head circumference, abdominal circumference, and femur length, and estimated fetal weight was calculated. We used linear mixed models with cubic splines for the fixed effects and random effects to flexibly model ultrasound trajectories. We computed velocity percentiles in 2 ways: (1) difference between 2 consecutive weekly measurements (ie, weekly velocity), and (2) difference between any 2 ultrasounds at a clinically reasonable difference between 2 gestational ages (ie, velocity calculator). We compared correlation between fetal growth velocity percentiles and estimated fetal weight percentiles at 4-week intervals, with 32 (±1) weeks' gestation for illustration. Growth velocity was computed as estimated fetal growth rate (g/wk) between ultrasound at that gestational age and from prior visit [ie, for 28-32 weeks' gestational age: velocity = (estimated fetal weight 32-28)/(gestational age 32-28)]. We examined differences in birthweight by whether or not estimated fetal weight and estimated fetal weight velocity were <5th or ≥5th percentiles using χ2. RESULTS: Fetal growth velocity was nonmonotonic, with acceleration early in pregnancy, peaking at 13, 14, 15, and 16 weeks for biparietal diameter, head circumference, femur length, and abdominal circumference, respectively. Biparietal diameter, head circumference, and abdominal circumference had a second acceleration at 19-22, 19-21, and 27-31 weeks, respectively. Estimated fetal weight velocity peaked around 35 weeks. Fetal growth velocity varied slightly by race/ethnicity although comparisons reflected differences for parameters at various gestational ages. Estimated fetal weight velocity percentiles were not highly correlated with fetal size percentiles (Pearson r = 0.40-0.41, P < .001), suggesting that these measurements reflect different aspects of fetal growth and velocity may add additional information to a single measure of estimated fetal weight. At 32 (SD ± 1) weeks, if both estimated fetal weight velocity and size were <5th percentile, mean birthweight was 2550 g; however, even when size remained <5th percentile but velocity was ≥5th percentile, birthweight increased to 2867 g, reflecting the important contribution of higher growth velocities. For estimated fetal weight ≥5th percentile, but growth velocity <5th, birthweight was smaller (3208 vs 3357 g, respectively, P < .001). CONCLUSION: We provide fetal growth velocity data to complement our previous work on fetal growth size standards, and have developed a calculator to compute fetal growth velocity. Preliminary findings suggest that growth velocity adds additional information over knowing fetal size alone.

Supplemental Oxygen Study: A Randomized Controlled Study on the Effect of Maternal Oxygen Supplementation during Planned Cesarean Delivery on Umbilical Cord Gases.

OBJECTIVE: The aim was to determine the fetal umbilical blood gas effects of supplemental maternal oxygenation compared with room air (RA) during term planned cesarean delivery. METHODS: This is a prospective randomized controlled study of singleton planned cesarean deliveries randomized to receive supplemental oxygen (O2) at 10 L per minute (L/min) via facemask or RA. Umbilical cord gases were collected. The primary outcome was umbilical arterial pH level. Secondary outcomes included umbilical cord values and maternal and neonatal outcomes. Data were expressed as median ± interquartile range (IQR). RESULTS: Seventy subjects in total were enrolled, with 65 subjects available for analysis. The median umbilical arterial pO2 was significantly increased in the supplemental O2 group (18 [13.5-20.5] mm Hg) versus RA group (16 [12-18] mm Hg), p = 0.04). The median umbilical venous pO2 was significantly increased in the supplemental O2 group (32 [26.5-36.0] mm Hg) versus RA group (28.5 [22-34.3] mm Hg), p = 0.04). There were no significant differences with other umbilical blood gas values and composite maternal or neonatal complications. CONCLUSION: Subjects with term singleton gestations receiving O2 at 10 L/min during cesarean delivery compared with RA demonstrated no significant change in umbilical cord pH values. There was a significant increase in umbilical cord arterial and venous O2 levels in those receiving O2.

Association of Maternal Obesity With Longitudinal Ultrasonographic Measures of Fetal Growth: Findings From the NICHD Fetal Growth Studies-Singletons.

Importance: Despite the increasing prevalence of pregravid obesity, systematic evaluation of the association of maternal obesity with fetal growth trajectories is lacking. Objective: To characterize differences in fetal growth trajectories between obese and nonobese pregnant women, and to identify the timing of any observed differences. Design, Setting, and Participants: The Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies-Singletons study enrolled cohorts of pregnant women at 12 US health care institutions. Obese women (with prepregnancy body mass index > 30) and nonobese women (prepregnancy body mass indexes, 19-29.9) without major chronic diseases were recruited between 8 weeks and 0 days' gestation and 13 weeks and 6 days' gestation. A mixed longitudinal randomization scheme randomized participants into 1 of 4 schedules for 2-dimensional and 3-dimensional ultrasonograms to capture weekly fetal growth data throughout the remainder of their pregnancies. Main Outcomes and Measures: On each ultrasonogram, fetal humerus length, femur length, biparietal diameter, head circumference, and abdominal circumference were measured. Fetal growth curves were estimated using linear mixed models with cubic splines. Median differences in the fetal measures at each gestational week of the obese and nonobese participants were examined using the likelihood ratio and Wald tests after adjustment for maternal characteristics. Results: The study enrolled 468 obese and 2334 nonobese women between 8 weeks and 0 days' gestation and 13 weeks and 6 days' gestation. After a priori exclusion criteria, 443 obese and 2320 nonobese women composed the final cohort. Commencing at 21 weeks' gestation, femur length and humerus length were significantly longer for fetuses of obese woman than those of nonobese women. Differences persisted in obese and nonobese groups through 38 weeks' gestation (median femur length, 71.0 vs 70.2 mm; P = .01; median humerus length, 62.2 vs 61.6 mm; P = .03). Averaged across gestation, head circumference was significantly larger in fetuses of obese women than those of nonobese women (P = .02). Fetal abdominal circumference was not greater in the obese cohort than in the nonobese cohort but was significantly larger than in fetuses of normal-weight women (with body mass indexes between 19.0-24.9) commencing at 32 weeks (median, 282.1 vs 280.2 mm; P = .04). Starting from 30 weeks' gestation, estimated fetal weight was significantly larger for the fetuses of obese women (median, 1512 g [95% CI, 1494-1530 g] vs 1492 g [95% CI, 1484-1499 g]) and the difference grew as gestational age increased. Birth weight was higher by almost 100 g in neonates born to obese women than to nonobese women (mean, 3373.2 vs 3279.5 g). Conclusions and Relevance: As early as 32 weeks' gestation, fetuses of obese women had higher weights than fetuses of nonobese women. The mechanisms and long-term health implications of these findings are not yet established.