Mode of delivery and the survival of macrosomic infants in the United States, 1995-1999

Influence of Physical Activity during Pregnancy on Birth Weight: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Birth weight is a marker that is often referred to determine newborn health, potential growth trajectories and risk of future disease. Accordingly, interventions to promote appropriate and healthy birth weight have been extensively studied and implemented in pregnancy. In particular, physical activity in pregnancy is recommended to promote appropriate fetal development and newborn birth weight. This systematic review and meta-analyses aimed to summarize the effect of physical activity during pregnancy specifically from randomized controlled trials on the following outcomes: birth weight, macrosomia, low birth weight, being large for the gestational age, and being small for the gestational age (Registration No.: CRD42022370729). 63 studies (16,524 pregnant women) were included. There was a significant negative relationship between physical activity during pregnancy and macrosomia (z = 2.16; p = 0.03; RR = 0.79, 95% CI = 0.63, 0.98, I2 = 29%, Pheterogeneity = 0.09). No other significant relationships were found. Promoting physical activity during pregnancy may be an opportune time to reduce the risk of future chronic disease, such as obesity, through the prevention of macrosomia and the promotion of appropriate birth weights.

Incidence of infant mortality and its predictors in East Africa using Gompertz gamma shared frailty model

Background

Globally, infant mortality is a major public health concern and a sensitive indicator of countries' socio-economic and health status. Despite the substantial reduction of under-five mortality in sub-Saharan African countries specifically in East Africa, the infant mortality rate remains highest and too far below to achieve the WHO target. As to our search of the literature is concerned, there is a dearth of evidence on the incidence and predictors of infant mortality in East Africa. Therefore, this study investigated the incidence of infant mortality and its predictors in East Africa.

Methods

The present study has utilized 138,803 weighted samples from Demographic and Health Surveys (DHSs) of 12 East African countries. Considering the hierarchical nature of DHS data shared frailty parametric survival models were fitted and compared based on deviance (-2LLR), AIC, and BIC. Gompertz gamma shared frailty model was the best-fitted model for the data since it had the lowest deviance, AIC, and BIC values. Variables with a p-value < 0.2 in the bi-variable analysis were considered for the multivariable analysis. In the multivariable Gompertz gamma shared analysis, the Adjusted Hazard Ratio (AHR) with 95% Confidence Interval (CI) was reported to declare the significant predictors of infant mortality.

Results

The infant mortality rate in East Africa was 41.41 per 1000 live births. Mothers aged 25–34 years, wanted birth, health facility delivery, 1–3 ANC visit, being 2nd- 4th birth order, 5th and above, the birth interval of 24–48 months, and birth interval of 49 months and above were significantly associated with lower risk of infant mortality. Whereas women who didn’t have formal education, women who didn't participate in making health care decisions making, being male children, cesarean delivery, small size at birth, and large size at birth were significantly associated with a higher risk of infant mortality.

Conclusion

Despite the substantial progress in improving maternal and child health, this study showed that infant mortality is still a major public health concern in East Africa. Maternal age, place of delivery, maternal education, birth size, sex of the child, mode of delivery, women's autonomy, birth order, birth interval, and ANC visit were found to be significant predictors of infant mortality. Therefore, public health interventions enhancing health facility delivery, ANC visit, maternal education, birth spacing, and empowering women are crucial for reducing the incidence of infant mortality in East Africa.

Pre-pregnancy maternal obesity, macrosomia, and risk of stillbirth: A population-based study

OBJECTIVE

An examination of the synergistic effects of maternal obesity and macrosomia on the risk of stillbirth is lacking. The purpose of this study was to determine the association between fetal macrosomia, maternal obesity, and the risk of stillbirth.

METHODS

This retrospective cross-sectional study used the CDC's Birth Data and Fetal Death Data files for 2014-2017 [n = 10,043,398‬ total births; including 48,799 stillbirths]. The exposure was fetal macrosomia stratified by obesity subtypes (I-III). The outcome was the risk of stillbirth. We also controlled for potential and known confounding factors in adjusted models. Adjusted Relative Risks (ARR) were estimated with log-binomial regression models.

RESULTS

The rate of stillbirth was higher among macrosomic infants born to mothers with obesity compared to those without (6.55 vs. 0.54 per 1000 total births). After controlling for confounding, women with obesity types II and III were at increased risk for stillbirth [Obesity II ARR = 2.37 (2.07-2.72); Obesity III ARR = 9.06 (7.61-10.78)].

CONCLUSIONS FOR PRACTICE

Obesity-related fetal overgrowth is a significant risk factor for stillbirth, especially among women with type II and type III obesity. This finding highlights the need for more effective clinical and public health strategies to address pre-pregnancy obesity and to optimize gestational weight gain.

Phenotypes of fetal macrosomia and risk of stillbirth among term deliveries over the previous four decades

OBJECTIVES

To evaluate the association between macrosomia and stillbirth over the previous four decades and to determine the consistency of the relationship.

METHODS

This was a population-based retrospective cohort study using United States Natality and Fetal Death Data from 1982 to 2017 and restricted to the gestational age range of 37-41 weeks inclusive. Macrosomia was defined as birthweight ≥4000 g and subdivided into its grades as previously recommended: grade 1 (4000-4499 g), grade 2 (4500-4999 g), and grade 3 (≥5000 g). We calculated temporal trends of stillbirth among fetuses with macrosomia over the years using joinpoint regression. We generated odds ratios from adjusted binomial logistic regression models to examine the association between macrosomia and risk of stillbirth stratified by grades using normal-weight infants (2500-3999 g) as referent.

RESULTS

Within the fetal macrosomia group, the rate of stillbirth declined from 2.04/1000 in 1982 to 1.05/1000 by the end of the study period (2017), representing a drop of about 48.5%. For the normal-weight fetuses, stillbirth rate declined from 1.95/1000 to 0.83/1000, equivalent to a decline of 57.4%. Macrosomia was significantly associated with elevated risk for stillbirth: grade 2 (OR = 1.27; 95% CI = 1.22-1.32) and grade 3 (OR = 5.97; 95% CI = 5.69-6.22).

CONCLUSIONS

Fetal macrosomia is a significant risk factor for fetal demise with the worst intrauterine survival observed among those classified as grade 3. Fetal macrosomia is a heterogeneous rather than a homogeneous entity in terms of risk profiles, and this needs to be considered in future policy guidelines.

Trends in the incidence of fetal macrosomia and its phenotypes in the United States, 1971-2017

PURPOSE

Studies have reported a surge in the prevalence of obesity among various demographic groups including pregnant women in the U.S. Given the association between maternal obesity and risk of fetal macrosomia, we hypothesized that the incidence of fetal macrosomia will be on the rise in the U.S. We examined trends in fetal macrosomia and macrosomia phenotypes in the U.S. among singleton live births within the gestational age of 28-42 weeks inclusive.

METHODS

This was a retrospective cohort study covering the period 1971-2017 using U.S. Natality Data files. We applied Joinpoint regression models to derive the average annual percentage change in the outcome. We measured incidence and trends of fetal macrosomia which was defined as birth weight ≥ 4000 g. We further subdivided macrosomia into its phenotypes as previously recommended: Grade 1 (4000-4499 g), Grade 2 (4500-4999 g) and Grade 3 (≥ 5000 g).

RESULTS

A total of 147,331,305 singleton births over the entire study period of 47 years were analyzed. From a baseline incidence of 8.84%, the rate of fetal macrosomia declined to 8.07% by the end of the study representing a drop of 8.70% in relative terms. The greatest drop was among infants with Grade 3 macrosomia, the most severe and lethal phenotype. The most impactful factors were maternal age and gestational weight gain.

CONCLUSION

This study is the largest population-based study conducted regarding fetal macrosomia. The rate of fetal macrosomia declined over the previous 5 decades with the most substantial drop observed in the phenotype with the worst prognosis.

Perinatal outcomes of maternal overweight and obesity in term infants: a population-based cohort study in Canada

The objective of this study was to assess the impact of increased pre-pregnancy maternal body mass index (BMI) on perinatal outcomes in term, singleton pregnancies who received prenatal care in community-based practices. The sample of 1996 infants included in the study was drawn from the All Our Babies Study, a prospective pregnancy cohort from Calgary. Multivariable logistic regression explored the relationship between the main outcomes, infant birth weight, Apgar score, admission to neonatal intensive care (NICU) and newborn duration of hospitalization, and BMI prior to pregnancy. Approximately 10% of the infants were macrosoms, 1.5% had a low Apgar score (<7 at 5 min), 6% were admitted to intensive care and 96% were discharged within 48 h after delivery. Although the infants of overweight and obese women were more likely to have increased birth weight as compared to infants of normal weight women, there were no differences in Apgar score, admission to NICU, or length of postnatal hospital stay among groups. This study suggests that in otherwise healthy term, singleton pregnancies, obesity does not seem to increase the risk of severe fetal impairment, neonatal admission to intensive care or duration of postnatal hospitalization.

Does induction of labor for constitutionally large-for-gestational-age fetuses identified in utero reduce maternal morbidity?

BACKGROUND

The number of infants with a birth weight > 97th percentile for gestational age has increased over the years. Although some studies have examined the interest of inducing labor for fetuses with macrosomia suspected in utero, only a few have analyzed this suspected macrosomia according to estimated weight at each gestational age. Most studies have focused principally on neonatal rather than on maternal (and still less on perineal) outcomes. The principal aim of this study was to assess whether a policy of induction of labor for women with a constitutionally large-for-gestational-age fetus might reduce the occurrence of severe perineal tears; the secondary aims of this work were to assess whether this policy would reduce either recourse to cesarean delivery during labor or neonatal complications.

METHODS

This historical cohort study (n = 3077) analyzed records from a French perinatal database. Women without diabetes and with a cephalic singleton term pregnancy were eligible for the study. We excluded medically indicated terminations of pregnancy and in utero fetal deaths. Among the pregnancies with fetuses suspected, before birth, of being large-for-gestational-age, we compared those for whom labor was induced from ≥ 37 weeks to ≤ 38 weeks+ 6 days (n = 199) to those with expectant obstetrical management (n = 2878). In this intention-to-treat analysis, results were expressed as crude and adjusted relative risks.

RESULTS

The mean birth weight was 4012 g ± 421 g. The rate of perineal lesions did not differ between the two groups in either primiparas (aRR: 1.06; 95% CI: 0.86-1.31) or multiparas (aRR: 0.94; 95% CI: 0.84-1.05). Similarly, neither the cesarean rate (aRR: 1.11; 95% CI: 0.82-1.50) nor the risks of resuscitation in the delivery room or of death in the delivery room or in the immediate postpartum or of neonatal transfer to the NICU (aRR = 0.94; 95% CI: 0.59-1.50) differed between the two groups.

CONCLUSIONS

A policy of induction of labor for women with a constitutionally large-for-gestational-age fetus among women without diabetes does not reduce maternal morbidity.

Is prenatal identification of fetal macrosomia useful?

OBJECTIVES

To determine whether prenatal identification of macrosomia (≥4000g) reduces neonatal complications and maternal perineal lesions during delivery.

STUDY DESIGN

This historical cohort study (n=14,684 from the National perinatal database of the Audipog Association, France) included women with cephalic singleton term pregnancies. Among the babies born with macrosomia, we compared those who had been identified as such in utero (n=1211) with those who were not (n=13,473). The principal outcome was a composite variable defined as resuscitation in the delivery room, death in the delivery room or the immediate postpartum period, or transfer to a neonatal intensive care unit (NICU). The secondary outcome measures were neonatal trauma, 5-min Apgar score (≤4 and <7), and maternal perineal lesions. Results are expressed as crude relative risks and adjusted odds ratios.

RESULTS

The mean birthweight in the cohort was 4229g±219. The adjusted OR for the principal outcome defined above was 1.15 (95% CI: 0.89-1.50) in the group identified prenatally as macrosomic compared with the others (10.8% vs. 8.5%). The risk of neonatal trauma was higher in prenatally identified babies (adjusted OR: 1.80; 95% CI: 1.34-2.42). The 5-min Apgar score and the perineal lesion rate did not differ significantly between the groups. The a posteriori study power according to our results with α=0.05 was 84% (one-sided test).

CONCLUSIONS

Among babies born with macrosomia, in utero identification did not improve neonatal or maternal outcomes.

Impending macrosomia: will induction of labour modify the risk of caesarean delivery?

OBJECTIVE

To compare the annual incidence rates of caesarean delivery between induction of labour and expectant management in the setting of macrosomia.

DESIGN

This is a retrospective cohort study.

SETTING

Deliveries in the USA in 2003.

POPULATION

Singleton births of macrosomic neonates to low-risk nulliparous women at 39 weeks of gestation and beyond.

METHODS

Women who had induction of labour at 39 weeks of gestation with a neonatal birthweight of 4000 ± 125 g (3875-4125 g) were compared with women who delivered (either induced or spontaneous labour) at 40, 41 or 42 weeks (i.e. expectant management), assuming an intrauterine fetal weight gain of 200 g per additional week of gestation. Similar comparisons were made at 40 and 41 weeks of gestation. Chi-square test and multivariable logistic regression analysis were used for statistical comparison.

MAIN OUTCOME MEASURES

Method of delivery, 5-minute Apgar scores, neonatal injury.

RESULTS

There were 132,112 women meeting the study criteria. In women whose labours were induced at 39 weeks and who delivered a neonate with a birthweight of 4000 ± 125 g, the frequency of caesarean was lower compared with women who delivered at a later gestational age (35.2% versus 40.9%; adjusted OR 1.25, 95% CI 1.17-1.33). This trend was maintained at both 40 weeks (36.1% versus 42.6%; adjusted OR 1.31, 95% CI 1.23-1.40) and 41 weeks (38.9% versus 41.8%; adjusted OR 1.16, 95% CI 1.06-1.28) of gestation.

CONCLUSIONS

In the setting of known birthweight, it appears that induction of labour may reduce the risk of caesarean delivery. Future research should concentrate on clinical and radiological methods to better estimate birthweight to facilitate improved clinical care. These findings deserve examination in a large, prospective, randomised trial.

Fetal macrosomia and pregnancy outcomes

BACKGROUND

Pregnancies with a macrosomic fetus comprise a subgroup of high-risk pregnancies. There is uncertainty in the clinical management and outcomes of such pregnancies.

AIM

We sought to examine clinical management and maternal and fetal outcomes in pregnancies with macrosomic infants at Royal Brisbane and Women's Hospital (RBWH).

METHODS

Data from 276 macrosomic births (weighing > or = 4500 g) and 294 controls (weighing 3250-3750 g) delivered during 2002-2004 at RBWH were collected from the hospital database. Univariate and logistic regression analyses were performed for maternal risk factors and maternal and neonatal outcomes that were associated with fetal macrosomia.

RESULTS

Macrosomia was more than two times likely in women with body mass index (BMI) of > 30 kg/m(2) (odds ratio (OR) 2.41, 95% confidence interval (CI) 1.26-4.61) and in male infant sex (OR 2.05, 95% CI 1.35-3.12), and four times more likely in gestation of > 40 weeks (OR 3.93, 95% CI 1.99-7.74). Maternal smoking reduced the risk of fetal macrosomia (OR 0.27, 95% CI 0.14-0.51). Macrosomia was associated with nearly two times higher risk of emergency caesarean section (OR 1.75, 95% CI 1.02-2.97) and maternal hospital stay of > 3 days (OR 1.66, 95% CI 1.11-2.50), and four times higher risk of shoulder dystocia (OR 4.08, 95% CI 1.62-10.29). Macrosomic infants were twice as likely to have resuscitation (OR 2.21, 95% CI 1.46-3.34) and intensive care nursery admission (OR 1.89, 95% CI 1.03-3.46).

CONCLUSION

Macrosomia was associated with an increased risk of adverse maternal and neonatal health outcomes. Optimal management strategies of macrosomic pregnancies need evaluation.

How big is too big? The perinatal consequences of fetal macrosomia

OBJECTIVE

The objective of the study was to examine the birthweight at which risks of perinatal death, neonatal morbidity, and cesarean delivery begin to rise and the causes and timing (antenatal, early or late neonatal, or postneonatal) of these risks.

STUDY DESIGN

This was a cohort study based on 1999-2001 US-linked stillbirth, live birth, and infant death records. Singletons weighing 2500 g or larger born to white non-Hispanic mothers at 37-44 weeks of gestation were selected (n = 5,983,409).

RESULTS

Infants with birthweights from 4000 to 4499 g were not at increased risk of mortality or morbidity vs those at 3500-3999 g, whereas those 4500-4999 g had significantly increased risks of stillbirth, neonatal mortality (especially because of birth asphyxia), birth injury, neonatal asphyxia, meconium aspiration, and cesarean delivery. Births at 5000 g or larger had even higher risks, including risk of sudden infant death syndrome.

CONCLUSION

Birthweight greater than 4500 g, and especially greater than 5000 g, is associated with increased risks of perinatal and infant mortality and morbidity.

Macrosomic births at Mostar Clinical Hospital: a 2-year review

The aim of this research was to determine the incidence, risk factors and perinatal outcome of the macrosomic infants (birth weight > or = 4000 g). The retrospective research was performed using a case-control study conducted at Mostar Clinical Hospital. Total of 379 women gave singleton term births to macrosomic newborn in the period from January 1st, 2004 to December 31st, 2005 (observed group). Another 379 singleton normal birthweight term newborns (birth weight < 4000 g, but not small for gestational age), of the same maternal parity and age, who were delivered in the same period, formed the control group. The incidence of macrosomic births was 13, 1%. In the study group, significantly higher number of cases of postdatism (> 42 weeks of gestation) (P<0,001), maternal obesity (prepregnancy BMI> 26 kg/m2) (P<0,001), gestational diabetes mellitus (P=0,033), hypertension (P=0,025) and male infant (P<0,001) were observed. Cesarean delivery (P<0,001), intrapartal complications (cephalopelvic disproportion P<0.001, perineal trauma P=0,042) and newborn birth trauma (clavicular fracture P=0,038, brachial palsy P=0,021) occurred significantly more often in the macrosomic group. There was only one fetal death in the macrosomic group. In the control group there were no cases of perinatal deaths. To conclude, it is important to emphasize the significance of proper diagnosis of fetal macrosomia and management of macrosomic birth, since we have seen a growing number of macrosomic births during the last decades, and have faced a problem of increased risks of adverse perinatal outcome.

Neighborhood economic disadvantage, violent crime, group density, and pregnancy outcomes in a diverse, urban population

Prior research has established associations between pregnancy outcomes and specific neighborhood characteristics, including economic disadvantage, violent crime, and racial/ethnic segregation. Recently, associations have also been found between various health outcomes and group density, the degree to which an individual is a racial or ethnic majority in his or her local community. The objective of this study was to determine the extent to which census tract economic disadvantage, violent crime rate, and group density are associated with pregnancy outcomes among White, Black, and Hispanic infants in a large metropolitan setting. This cross-sectional study utilized 1990 census data, 1991 crime data, and 1991 birth certificate information for singleton live births in Chicago, Illinois. Results show substantial racial segregation in Chicago, with 35% of census tracts having more than 90% Black residents and 45% of census tracts having fewer than 10% Black residents. After stratifying by maternal race/ethnicity, we used multilevel analyses to model pregnancy outcomes as a function of individual and census tract characteristics. Among all racial/ethnic groups, violent crime rate accounted for most of the negative association between tract economic disadvantage and birth weight. Group density was also associated with birth weight but this association was stronger among Whites and Hispanics than among Blacks. Further analysis revealed that group density was more strongly associated with preterm birth while violent crime rate was more strongly associated with small for gestational age. These results suggest that group density and violent crime may impact birth weight via different mechanisms.