Estimating gestational age at birth from fundal height and additional anthropometrics: a prospective cohort study.

OBJECTIVE: Accurate assessment of gestational age (GA) is critical to paediatric care, but is limited in developing countries without access to ultrasound. Our objectives were to assess the accuracy of prediction of GA at birth and preterm birth classification using routinely collected anthropometry measures. DESIGN: Prospective cohort study. SETTING: United States. POPULATION OR SAMPLE: A total of 2334 non-obese and 468 obese pregnant women. METHODS: Enrolment GA was determined based on last menstrual period, confirmed by first-trimester ultrasound. Maternal anthropometry and fundal height (FH) were measured by a standardised protocol at study visits; FH alone was additionally abstracted from medical charts. Neonatal anthropometry measurements were obtained at birth. To estimate GA at delivery, we developed three predictor models using longitudinal FH alone and with maternal and neonatal anthropometry. For all predictors, we repeatedly sampled observations to construct training (60%) and test (40%) sets. Linear mixed models incorporated longitudinal maternal anthropometry and a shared parameter model incorporated neonatal anthropometry. We assessed models' accuracy under varied scenarios. MAIN OUTCOME MEASURES: Estimated GA at delivery. RESULTS: Prediction error for various combinations of anthropometric measures ranged between 13.9 and 14.9 days. Longitudinal FH alone predicted GA within 14.9 days with relatively stable prediction errors across individual race/ethnicities [whites (13.9 days), blacks (15.1 days), Hispanics (15.5 days) and Asians (13.1 days)], and correctly identified 75% of preterm births. The model was robust to additional scenarios. CONCLUSIONS: In low-risk, non-obese women, longitudinal FH measures alone can provide a reasonably accurate assessment of GA when ultrasound measures are not available. TWEETABLE ABSTRACT: Longitudinal fundal height alone predicts gestational age at birth when ultrasound measures are unavailable.

Spontaneous and indicated preterm delivery risk is increased among overweight and obese women without prepregnancy chronic disease.

OBJECTIVE: To investigate the independent impact of prepregnancy obesity on preterm delivery among women without chronic diseases by gestational age, preterm category and parity. DESIGN: A retrospective cohort study. SETTING: Data from the Consortium on Safe Labor (CSL) in the USA (2002-08). POPULATION: Singleton deliveries at ≥23 weeks of gestation in the CSL (43 200 nulliparas and 63 129 multiparas) with a prepregnancy body mass index (BMI) ≥18.5 kg/m2 and without chronic diseases. METHODS: Association of prepregnancy BMI and the risk of preterm delivery was examined using Poisson regression with normal weight as reference. MAIN OUTCOME MEASURES: Preterm deliveries were categorised by gestational age (extremely, very, moderate to late) and category (spontaneous, indicated, no recorded indication). RESULTS: Relative risk of spontaneous preterm delivery was increased for extremely preterm among obese nulliparas (1.26, 95% CI: 0.94-1.70 for overweight; 1.88, 95% CI: 1.30-2.71 for obese class I; 1.99, 95% CI: 1.32-3.01 for obese class II/III) and decreased for moderate to late preterm delivery among overweight and obese multiparas (0.90, 95% CI: 0.83-0.97 for overweight; 0.87, 95% CI: 0.78-0.97 for obese class I; 0.79, 95% CI: 0.69-0.90 for obese class II/III). Indicated preterm delivery risk was increased with prepregnancy BMI in a dose-response manner for extremely preterm and moderate to late preterm among nulliparas, as it was for moderate to late preterm delivery among multiparas. CONCLUSIONS: Prepregnancy BMI was associated with increased risk of preterm delivery even in the absence of chronic diseases, but the association was heterogeneous by preterm categories, gestational age and parity. TWEETABLE ABSTRACT: Obese nulliparas without chronic disease had higher risk for spontaneous delivery <28 weeks of gestation.

Neonatal complications associated with use of fetal scalp electrode: a retrospective study.

OBJECTIVES: To estimate the incidence and risk of complications associated with a fetal scalp electrode and to determine whether its application in the setting of operative vaginal delivery was associated with increased neonatal morbidity. DESIGN: Retrospective cohort study. SETTING: Twelve clinical centers with 19 hospitals across nine American Congress of Obstetricians and Gynecologists US districts. POPULATION: Women in the USA. METHODS: We evaluated 171 698 women with singleton deliveries ≥ 23 weeks of gestation in a secondary analysis of the Consortium on Safe Labor study between 2002 and 2008, after excluding conditions that precluded fetal scalp electrode application such as prelabour caesarean delivery. Secondary analysis limited to operative vaginal deliveries ≥ 34 weeks of gestation was also performed. MAIN OUTCOME MEASURES: Incidences and adjusted odds ratios with 95% confidence intervals of neonatal complications were calculated, controlling for maternal characteristics, delivery mode and pregnancy complications. RESULTS: Fetal scalp electrode was used in 37 492 (22%) of deliveries. In non-operative vaginal delivery, fetal scalp electrode was associated with increased risk of injury to scalp due to birth trauma (1.2% versus 0.9%; adjusted odds ratios 1.62; 95% confidence intervals 1.41-1.86) and cephalohaematoma (1.0% versus 0.9%; adjusted odds ratios 1.57; 95% confidence intervals 1.36-1.83). Neonatal complications were not significantly different comparing fetal scalp electrode with vacuum-assisted vaginal delivery and vacuum-assisted vaginal delivery alone or comparing fetal scalp electrode with forceps-assisted vaginal delivery and forceps-assisted vaginal delivery alone. CONCLUSIONS: We found increased neonatal morbidity with fetal scalp electrode though the absolute risk was very low. It is possible that these findings reflect an underlying indication for its use. Our findings support the use of fetal scalp electrodes when clinically indicated. TWEETABLE ABSTRACT: Neonatal risks associated with fetal scalp electrode use were low (injury to scalp 1.2% and cephalohaematoma 1.0%).

Comparison of methods for identifying small-for-gestational-age infants at risk of perinatal mortality among obese mothers: a hospital-based cohort study.

OBJECTIVE: To assess differences in small-for-gestational age (SGA) classifications for the detection of neonates with increased perinatal mortality risk among obese women and subsequently assess the association between prepregnancy body mass index (BMI) status and SGA. DESIGN: Hospital-based cohort. SETTING: Twelve US clinical centres (2002-08). POPULATION: A total of 114 626 singleton, nonanomalous pregnancies. METHODS: Data were collected using electronic medical record abstraction. Relative risks (RR) with 95% CI were estimated. MAIN OUTCOME MEASURES: SGA trends (birthweight < 10th centile) classified using population-based (SGAPOP ), intrauterine (SGAIU ) and customised (SGACUST ) references were assessed. The SGA-associated perinatal mortality risk was estimated among obese women. Using the SGA method most associated with perinatal mortality, the association between prepregnancy BMI and SGA was estimated. RESULTS: The overall perinatal mortality prevalence was 0.55% and this increased significantly with increasing BMI (P < 0.01). Among obese women, SGAIU detected the highest proportion of perinatal mortality cases (2.49%). Perinatal mortality was 5.32 times (95% CI 3.72-7.60) more likely among SGAIU neonates than non-SGAIU neonates. This is in comparison with the 3.71-fold (2.49-5.53) and 4.81-fold (3.41-6.80) increased risk observed when SGAPOP and SGACUST were used, respectively. Compared with women of normal weight, overweight women (RR = 0.82, 95% CI 0.78-0.86) and obese women (RR = 0.80; 95% CI 0.75-0.83) had a lower risk for delivering an SGAIU neonate. CONCLUSION: Among obese women, the intrauterine reference best identified neonates at risk of perinatal mortality. Based on SGAIU , SGA is less common among obese women but these SGA babies are at a high risk of death and remain an important group for surveillance. TWEETABLE ABSTRACT: SGA is less common among obese women but these SGA babies are at a high risk of death.

Placental characteristics and risks of maternal mortality 50 years after delivery.

INTRODUCTION: Adverse pregnancy outcomes such as preterm delivery and preeclampsia are associated with a higher maternal risk for subsequent cardiovascular disease (CVD) and all-cause mortality. While such pregnancy conditions are related to abnormal placentation, little research has investigated whether pathologic placental measures could serve as a risk factor for future CVD mortality in mothers. METHODS: Longitudinal study of 33,336 women from the Collaborative Perinatal Project (CPP; 1959-1966) linked to mortality information through December 2016. Pathologists took extensive morphological and histopathological measures. Apart from assessing associations with morphological features, we derived an overall composite score and specific inflammation-related, hemorrhage-related, and hypoxia-related pathologic placenta index scores. Cox regression estimated hazard ratios (HR) and 95% confidence intervals (CI) for mortality adjusting for covariates. RESULTS: Thirty-nine percent of women died with mean (standard deviation, SD) time to death of 39 (12) years. Mean (SD) placental weight and birthweight were 436 g (98) and 3156 g (566), respectively. Placenta-to-birthweight ratio was associated with all-cause mortality (adjusted HR 1.03: 1.01, 1.05 per SD in ratio). In cause-specific analyses, it was significantly associated with respiratory (HR 1.06), dementia (HR: 1.10) and liver (HR 1.04) related deaths. CVD, cancer, diabetes and kidney related deaths also tended to increase, whereas infection related deaths did not (HR 0.94; 0.83, 1.06). Placental measures of thickness, diameters, and histopathological measures grouped by inflammatory, hemorrhagic, or hypoxic etiology were not associated with mortality. DISCUSSION: Placental weight in relation to birthweight was associated with long-term maternal mortality but other histopathologic or morphologic features were not.