Gestational weight gain and risk of infant death in the United States

Do maternal BMI and gestational weight gain equally affect the risk of infant hypoxic and traumatic events?

BACKGROUND

Small (SGA) and large (LGA) for gestational age infants have higher risks of infant morbidity when compared to those who are appropriate for gestational age (AGA). Increasing pre-pregnancy maternal BMI and gestational weight gain (GWG) are associated with higher risks of LGA and lower risks of SGA infants; however, their direct effects on infant morbidity are unknown. Therefore, we intended to 1) assess how maternal pre-pregnancy BMI, GWG, and birthweight (categorized as SGA, AGA or LGA) affect infant morbidity and 2) estimate at entry of care the risk of infant morbidity according to pre-pregnancy BMI and possible GWG.

METHODS

we used Consortium on Safe Labor data, a retrospective observational cohort study collecting pregnancy and birth data from 2002 to 2008 in 12 US centers. The association between maternal BMI, GWG and infant morbidity was estimated in singleton gestations delivering ≥ 37 weeks using binomial logistic regression. Hypoxic composite neonatal morbidity was defined as any the following: stillbirth, neonatal death, resuscitation at birth, NICU admission, intracranial hemorrhage, PVH grade III and IV, neonatal seizures, NEC, meconium aspiration, CPAP or mechanical ventilation, RDS, and sepsis. Traumatic composite neonatal morbidity included shoulder dystocia or birth injuries.

RESULTS

In this study of 110,594 mother-infant dyads, a total of 8,369 (7.6%) infants experienced hypoxic, while 2,134 (1.9%) developed traumatic morbidity. The risk of hypoxic morbidity among SGA, AGA and LGA infants increased when mothers were overweight (aOR 1.26 [95%CI 1.18-1.34]) or obese (class 1: aOR 1.3 [1.2-1.4]; class 2: aOR 1.7 [1.5-1.9]; class 3: aOR 1.8 [1.6-2]) as opposed to normal weight, and when GWG exceeded (aOR 1.08 [1.02-1.014]) rather than remained within recommendations. The risk of traumatic morbidity increased with maternal obesity (class 1: aOR 1.3 [1.1-1.5]), whilst it dropped with GWG below recommendations (aOR 0.7 [0.6-0.8]). The risk of hypoxic events estimated at entry of care increased with maternal overweight (aOR 1.27 [1.19-1.35]) or obesity (class 1: aOR 1.4 [1.2-1.5]; class 2: aOR 1.7 [1.5-1.9]; class 3: aOR 1.8 [1.6-2.1]), and with possible GWG above (aOR 1.09 [1.03-1.015]) recommendations. The risk of traumatic morbidity increased with overweight (aOR 1.1 [1-1.3]) or obesity (class 1: aOR 1.4 [1.2-1.6]; class 2: aOR 1.3 [1-1.6]), with possible GWG above (aOR 1.2 [1-1.3]), as opposed to below recommendations (aOR 0.7 [0.6-0.8]).

CONCLUSIONS

While maternal pre-pregnancy BMI and GWG equally affected traumatic morbidity, the former had a greater impact on hypoxic complications. Therefore, weight control prior to pregnancy is at least as effective as avoiding excessive gestational weight gain to prevent neonatal morbidity.

The impact of gestational weight gain on fetal and neonatal outcomes: the Araraquara Cohort Study

BACKGROUND

Gestational weight gain (GWG) is an important indicator for monitoring maternal and fetal health.

OBJECTIVE

To evaluate the effect of GWG outside the recommendations of the Institute of Medicine (IOM) on fetal and neonatal outcomes.

STUDY DESIGN

A prospective cohort study with 1642 pregnant women selected from 2017 to 2023, with gestational age ≤ 18 weeks and followed until delivery in the city of Araraquara, Southeast Brazil. The relationship between IOM-recommended GWG and fetal outcomes (abdominal subcutaneous tissue thickness, arm and thigh subcutaneous tissue area and intrauterine growth restriction) and neonatal outcomes (percentage of fat mass, fat-free mass, birth weight and length, ponderal index, weight adequateness for gestational age by the Intergrowth curve, prematurity, and Apgar score) were investigated. Generalized Estimating Equations were used.

RESULTS

GWG below the IOM recommendations was associated with increased risks of intrauterine growth restriction (IUGR) (aOR 1.61; 95% CI: 1.14-2.27), low birth weight (aOR 2.44; 95% CI: 1.85-3.21), and prematurity (aOR 2.35; 95% CI: 1.81-3.05), and lower chance of being Large for Gestational Age (LGA) (aOR 0.38; 95% CI: 0.28-0.54), with smaller arm subcutaneous tissue area (AST) (-7.99 g; 95% CI: -8.97 to -7.02), birth length (-0.76 cm; 95% CI: -1.03 to -0.49), and neonatal fat mass percentage (-0.85%; 95% CI: -1.12 to -0.58). Conversely, exceeding GWG guidelines increased the likelihood of LGA (aOR 1.53; 95% CI: 1.20-1.96), with lower 5th-minute Apgar score (aOR 0.42; 95% CI: 0.20-0.87), and increased birth weight (90.14 g; 95% CI: 53.30 to 126.99).

CONCLUSION

Adherence to GWG recommendations is crucial, with deviations negatively impacting fetal health. Effective weight control strategies are imperative.

Gestational weight gain among pregnant women in Ibadan, Nigeria: Pattern, predictors and pregnancy outcomes

BACKGROUND

Gestational weight gain (GWG) is a risk factor for adverse pregnancy outcomes, future obesity and chronic diseases among women. However, has not received much attention in many low and middle-income countries such as Nigeria. We investigated the pattern, associated factors and pregnancy outcomes of GWG in Ibadan, Nigeria, using the Ibadan Pregnancy Cohort Study (IbPCS).

METHODOLOGY

The IbPCS is a multicentre prospective cohort study conducted among 1745 pregnant women recruited from four health facilities in Ibadan, Nigeria. GWG, the primary outcome, was categorised according to the Institute of Medicine's classification into insufficient, adequate and excessive weight gain. Pregnancy outcomes were the secondary outcome variables. Logistic regression analysis (Adjusted odds ratios and 95% confidence interval CI) was used to examine associations, and Poisson regression analyses were used to investigate associations with outcomes.

RESULTS

Only 16.9% of women had optimal GWG, 56.8% had excessive GWG, and 26.9% had insufficient GWG. Excessive GWG was associated with high income '> #20,000-' (AOR: 1.64, 95% CI: 1.25-2.17), being overweight (AOR: 2.12, 95% CI: 1.52-2.95) and obese (AOR: 1.47, 95% CI: 1.02-2.13) after adjusting for confounders. In contrast, increased odds of insufficient GWG have associated women with depression (AOR: 1.70, 95% CI 1.17-2.47). There was no significant association between inappropriate GWG and pregnancy outcomes However, there was an increased odds for postpartum haemorrhage (AOR: 2.44, 95% CI 1.14-5.22) among women with obesity and excessive GWG.

CONCLUSIONS

Excessive GWG was the most typical form of GWG among our study participants and was associated with high maternal income, and being overweight or obese. GWG needs to be monitored during antenatal care, and interventions that promote appropriate GWG should be implemented among pregnant women in Nigeria.

Gestational Weight Gain and Birth Outcome: A Comparison of Methods of Accounting for Gestational Age

Cross-sectional studies of total gestational weight gain (GWG) and perinatal outcomes have used different approaches to operationalize GWG and adjust for duration of gestation. Using birth records from California (2007-2017), Nevada (2010-2017), and Oregon (2008-2017), we compared 3 commonly used approaches to estimate associations between GWG and cesarean delivery, small-for-gestational-age birth, and low birth weight (LBW): 1) the Institute of Medicine-recommended GWG ranges at a given gestational week, 2) total weight gain categories directly adjusting for gestational age as a covariate, and 3) weight-gain-for-gestational-age z scores derived from an external longitudinal reference population. Among 5,461,130 births, the 3 methods yielded similar conclusions for cesarean delivery and small-for-gestational-age birth. However, for LBW, some associations based on z scores were in the opposite direction of methods 1 and 2, paradoxically suggesting that higher GWG increases risk of LBW. This was due to a greater proportion of preterm births among those with high z scores, and controlling for gestational age in the z score model brought the results in line with the other methods. We conclude that the use of externally derived GWG z scores based on ongoing pregnancies can yield associations confounded by duration of pregnancy when the outcome is strongly associated with gestational age at delivery.

Neighborhood walkability and poverty predict excessive gestational weight gain: A cross-sectional study in New York City

OBJECTIVE

This study evaluated associations between neighborhood-level characteristics and gestational weight gain (GWG) in a population-level study of 2015 New York City births.

METHODS

Generalized linear mixed-effects models were used to estimate odds ratios (ORs) for associations between neighborhood-level characteristics (poverty, food environment, walkability) within 1 km of a residential Census block centroid and excessive or inadequate GWG compared with recommended GWG. All models were adjusted for individual-level sociodemographic characteristics.

RESULTS

Among the sample of 106,285 births, 41.8% had excessive GWG, and 26.3% had inadequate GWG. Residence in the highest versus lowest quartile of neighborhood poverty was associated with greater odds of excessive GWG (OR: 1.17, 95% CI: 1.08-1.26). Residence in neighborhoods in the quartile of highest walkability compared with the quartile of lowest walkability was associated with lower odds of excessive GWG (OR: 0.87, 95% CI: 0.81-0.93). Adjustment for prepregnancy BMI attenuated the associations for neighborhood poverty, but not for walkability. Neighborhood variables were not associated with inadequate GWG.

CONCLUSIONS

These analyses indicate that greater neighborhood walkability is associated with lower odds of excessive GWG, potentially from differences in pedestrian activity during pregnancy. This research provides further evidence for using urban design to support healthy weight status during pregnancy.

Developing a Prenatal Nutrition Tool: A Process of Evidence, Collaboration, and Consultation

The Prenatal Nutrition Tool was created for care providers that work with pregnant clients and aims to support focused conversations on nutrition topics that influence maternal and infant health outcomes. A systematic 9-step product development process that combined findings from the literature with perspectives of nutrition experts and care providers was used to develop the tool. The results of a literature review and a modified Delphi Process (to obtain expert opinion) laid the foundation for the tool content. The final tool incorporated client feedback. More specifically, client feedback helped to refine tool questions. The tool consists of 2 parts: a questionnaire (written survey) and a conversation guide. The questionnaire covers 4 key themes (pregnancy weight gain, multivitamins, life circumstances, overall food intake) in 13 questions. The conversation guide utilizes public health nutrition guidance documents to lead care providers in focused discussions with clients. The tool is not intended to be a screening tool for medical conditions or replace an in-depth prenatal nutrition assessment. The tool can be accessed by any care provider in Canada on the Alberta Health Services website at Prenatal Nutrition Tool | Alberta Health Services.

Association of Gestational Weight Gain With Infant Morbidity and Mortality in the United States

IMPORTANCE

The associations of gestational weight gain (GWG) with infant morbidity and mortality are unclear, and the existing recommendations for GWG have not been stratified by the severity of obesity.

OBJECTIVES

To identify optimal GWG ranges associated with reduced risks of infant morbidity and mortality across maternal body mass index (BMI) categories.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used US nationwide, linked birth and infant death data between 2011 and 2015 to assess the associations of GWG in 2.0-kg groups with infant morbidity and mortality and identified optimal GWG ranges associated with reduced risks of both outcomes, using multivariable logistic regression models. Statistical analysis was performed from February 11 to October 14, 2021.

EXPOSURE

Gestational weight gain equivalent to 40 weeks.

MAIN OUTCOMES AND MEASURES

The 2 main outcomes were (1) significant morbidity of the newborn infant, defined as any presence of assisted ventilation, admission to the neonatal intensive care unit, surfactant therapy, antibiotic therapy, or seizures; and (2) infant mortality younger than 1 year of age (<1 hour, 1-23 hours, 1-6 days, 7-27 days, or 28-365 days after birth).

RESULTS

In this study of 15 759 945 mother-infant dyads, the mean (SD) age of the women was 28.1 (5.9) years. Women gained a mean (SD) of 14.1 (7.3) kg during pregnancy, and the mean (SD) GWG decreased with BMI categories (underweight, 15.7 [6.4] kg; normal weight, 15.4 [6.2] kg; overweight, 14.2 [7.4] kg; obesity class 1, 12.2 [8.0] kg; obesity class 2, 10.3 [8.4] kg; obesity class 3, 8.2 [9.2] kg; P < .001). A total of 8.8% of the newborns experienced significant morbidity, with the lowest prevalence among infants delivered by women in the normal weight BMI class (8.0%) and the highest among infants delivered by women with class 3 obesity (12.4%); 0.34% of infants died within 1 year of birth, with the lowest prevalence among infants delivered by women in the normal weight BMI class (0.28%) and the highest among infants delivered by women with class 3 obesity (0.58%). Optimal GWG ranges were 12.0 to less than 24.0 kg for underweight and normal weight women, 10.0 to less than 20.0 kg for overweight women, 8.0 to less than 16.0 kg for women with class 1 obesity, 6.0 to less than 16.0 kg for class 2 obesity, and 6.0 to less than 10.0 kg for class 3 obesity. The lower bounds of the optimal GWG ranges appeared to be higher than the existing recommendations for overweight women (10.0 vs 7.0 kg) and for those with class 1 (8.0 vs 5.0 kg), class 2 (6.0 vs 5.0 kg), and class 3 (6.0 vs 5.0 kg) obesity.

CONCLUSIONS AND RELEVANCE

This study analyzed the associations of GWG with infant morbidity and mortality across BMI categories and found that inadequate GWG was associated with increased risks of adverse infant outcomes even for women with obesity. The results suggested that weight maintenance or weight loss should not be used as routine guidelines.

Late Gestation Maternal Feed Restriction Decreases Microbial Diversity of the Placenta While Mineral Supplementation Improves Richness of the Fetal Gut Microbiome in Cattle

Feed intake restriction impacts both humans and ruminants in late gestation, although it is unknown whether this adverse maternal environment influences the microbiome of the reproductive tract, and through it, the colonization of the fetal gut. A 2 × 2 factorial design including a 70% feed intake restriction (feed restricted 'FR' or control diets 'CON') and mineral supplementation (unsupplemented 'S-' or supplemented 'S+') was used to analyze these effects in multiparous cows (n = 27). Vaginal swabs were obtained 60, 30, and 10 days prior to the estimated calving date, along with neonatal rumen fluid and meconium. Placental tissues and efficiency measurements were collected. Microbial DNA was extracted for 16S sequencing of the V4 region. Feed restriction decreased the diversity of the placental microbiome, but not the vagina, while mineral supplementation had little impact on these microbial communities. Mineral supplementation did improve the richness and diversity of the fetal gut microbiomes in relation to reproductive microbes. These differences within the placental microbiome may influence individual health and performance. Adequate maternal nutrition and supplementation yielded the greatest placental efficiency, which may aid in the establishment of a healthy placental microbiome and fetal microbial colonization.

Race, ethnicity, WIC participation, and infant health disparities in the United States

PURPOSE

This study examines the association between race and ethnicity, participation in The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), and a series of infant health outcomes including infant mortality, low birth weight, preterm birth, extended infant hospitalization, and stays in the neonatal infant care unit (NICU).

METHODS

Data are from the Pregnancy Risk Assessment Monitoring System (PRAMS), 2009-2017. Moderation analyses were conducted to assess the association between maternal race and ethnicity, WIC participation, and infant health.

RESULTS

Results indicate infants born to Black women and to a lesser extent Hispanic woman are in worse health than those born to White mothers in the United States. However, participation in WIC is associated with reductions in the gap in infant health experienced by racial and ethnic minorities.

CONCLUSIONS

Prenatal WIC participation is associated with improvements in the health of Black and Hispanic infants and reduced racial and ethnic disparities in infant health outcomes.

Monitoring gestational weight gain and prepregnancy BMI using the 2009 IOM guidelines in the global population: a systematic review and meta-analysis

BACKGROUND

Previous studies have reported a high prevalence of excessive gestational weight gain (GWG) in women with prepregnancy BMI classified as overweight and obese. However, the joint evidence regarding GWG and prepregnancy BMI in the worldwide population has not been synthesized. Thus, this systematic review and meta-analysis aimed to estimate global and regional mean GWG and the prevalence of GWG above, within and below 2009 Institute of Medicine (IOM) guidelines. Second, we aimed to estimate global and regional prepregnancy BMI and the prevalence of BMI categories according to World Health Organization (WHO) classification.

METHODS

We searched Medline, Embase, the Cochrane Library and Web of Science to identify observational studies until 9 May 2018. We included studies published from 2009 that used 2009 IOM guidelines, reporting data from women in general population with singleton pregnancies. The 2009 IOM categories for GWG and the WHO categories for prepregnancy BMI were used. DerSimonian and Laird random effects methods were used to estimate the pooled and their respective 95% confidence intervals (95% CIs) of the mean and by category rates of GWG and prepregnancy BMI, calculated by global and regions.

RESULTS

Sixty-three published studies from 29 countries with a total sample size of 1,416,915 women were included. The global prevalence of GWG above and below the 2009 IOM guidelines, was 27.8% (95% CI; 26.5, 29.1) and 39.4% (95% CI; 37.1, 41.7), respectively. Furthermore, meta-regression analyses showed that the mean GWG and the prevalence of GWG above guidelines have increased. The global prevalence of overweight and obesity, was 23.0% (95% CI; 22.3, 23.7) and 16.3% (95% CI; 15.4, 17.4), respectively. The highest mean GWG and prepregnancy BMI were in North America and the lowest were in Asia.

CONCLUSIONS

Considering the high prevalence of GWG above the 2009 IOM guidelines and women with overweight/obesity and their continuously increasing trend in most regions, clinicians should recommend lifestyle interventions to improve women's weight during reproductive age. Due to regional variability, these interventions should be adapted to each cultural context.

TRIAL REGISTRATION

Prospectively registered with PROSPERO ( CRD42018093562 ).

Gestational Weight Gain: Update on Outcomes and Interventions

PURPOSE OF REVIEW

Gestational weight gain is a modifiable risk factor for adverse perinatal outcomes. After the Institute of Medicine (IOM) released updated recommendations for gestational weight gain in 2009, a multitude of studies were released examining the recommendations, particularly for women with obesity. As the obesity epidemic continues, many physicians are interested in minimizing gestational weight gain for all women. Our aim was to review the evidence for the association of gestational weight gain and perinatal outcomes, particularly for weight gain outside the IOM guidelines.

RECENT FINDINGS

Gestational weight gain is associated with several adverse perinatal outcomes including fetal growth, preterm delivery, cesarean delivery, gestational diabetes, hypertensive disorders of pregnancy, and infant mortality as well as with long-term offspring metabolic health outcomes. Multiple randomized controlled trials have been conducted evaluating the efficacy of lifestyle intervention on gestational weight gain, and while lifestyle interventions may alter gestational weight gain, they have not been associated with improvement in perinatal outcomes. Weight loss during pregnancy is associated with decreased risks of macrosomia and cesarean delivery; however, given an association with low birth weight, it is not currently recommended. Excessive gestational weight gain is known to be associated with multiple adverse fetal and maternal outcomes. Lifestyle interventions during pregnancy may be helpful in decreasing excessive weight gain, but have not shown to be beneficial for most adverse pregnancy outcomes. More research is needed before making recommendations for weight loss in women with obesity during pregnancy.

Influence of pre-pregnancy body mass index (p-BMI) and gestational weight gain (GWG) on DNA methylation and protein expression of obesogenic genes in umbilical vein

Understanding the regulatory mechanisms that affect obesogenic genes expression in newborns is essential for early prevention efforts, but they remain unclear. Our study aimed to explore whether the maternal p-BMI and GWG were associated with regulatory single-locus DNA methylation in selected obesogenic genes. For this purpose, DNA methylation was assayed by Methylation-Sensitive High Resolution Melting (MS-HRM) technique and Sanger allele-bisulfite sequencing in fifty samples of umbilical vein to evaluate glucosamine-6-phosphate deaminase 2 (GNPDA2), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α), and leptin receptor (LEPR) genes. Correlations between DNA methylation levels and indicators of maternal nutritional status were carried out. Western blotting was used to evaluate protein expression in extracts of the same samples. Results indicated that GNPDA2 and PGC1α genes have the same level of DNA methylation in all samples; however, a differential DNA methylation of LEPR gene promoter was found, correlating it with GWG and this correlation is unaffected by maternal age or unhealthy habits. Furthermore, leptin receptor (Lep-Rb) was upregulated in samples that showed the lowest levels of DNA methylation. This study highlights the association between poor GWG and adjustments on obesogenic genes expression in newborn tissues with potential consequences for development of obesity in the future.

Association between time interval from bariatric surgery to pregnancy and maternal weight outcomes

BACKGROUND

The majority of patients having bariatric surgery are reproductive-age women who are advised to delay pregnancy for at least 12 months after surgery. Many women become pregnant sooner and the association between gestational weight gain (GWG) and maternal long-term weight is unknown.

OBJECTIVES

The primary objective of this study was to compare weight outcomes in pregnancies occurring < 12 months versus ≥ 12 months after bariatric surgery. The secondary objectives were to determine the association between time interval from bariatric surgery to pregnancy and maternal nutritional status and maternal and neonatal outcomes.

STUDY DESIGN

This is a retrospective cohort study of women with singleton livebirths after bariatric surgery who received care at a single tertiary care center between 2009 and 2017. GWG was the difference in weight between the first prenatal visit and delivery. GWG adequacy was determined by the IOM 2009 guidelines according to prepregnancy BMI (inadequate, adequate, excessive). Postpartum weight retention was calculated as the difference between weight at first prenatal visit and measured postpartum weight. Weight outcomes along with maternal nutritional status and maternal and neonatal outcomes were compared between < 12 months versus ≥ 12 months after bariatric surgery with t-tests, Mann-Whitney U and chi-square tests, as appropriate.

RESULTS

Of the 76 pregnancies that met inclusion criteria, 36.8% occurred < 12 months (median 7.2 months) and 63.2% occurred ≥ 12 months after surgery (median 26.9 months). Of those with pregnancies < 12 months from surgery, 34% had a restrictive procedure (adjustable gastric band or sleeve gastrectomy) while 66% had a combined restrictive-malabsorptive procedure (Roux-en-Y gastric bypass). In the ≥ 12 months group, 42.3% had a restrictive procedure while 57.7% had a combined restrictive-malabsorptive procedure. There were no significant differences in maternal age, ethnicity or nulliparity between groups, but there were more women with obesity in the < 12 months group (75 vs. 52%, p = .03). The mean prepregnancy BMI in the < 12 months group was 34.3 vs. 31.2 kg/m² in the ≥ 12 months group. The < 12 months group had lower mean GWG (4.9 vs. 10.9 kg, p = .01) and higher frequency of weight loss during pregnancy (28.6 vs. 4.2%, p < .01) compared to the ≥ 12 months group. The < 12 months group had significantly less postpartum weight retention at 6 months compared to the ≥ 12 months group (-1.3 vs. 8.3 kg, p = .02). The < 12 months group had a higher prevalence of vitamin B12 deficiency (23.1 versus 4.9%, p = .05). There were no differences in hyperemesis, hypertensive disorders, gestational diabetes or delivery mode between groups (p > .05). There were no differences in gestational age at delivery, birth weight and small for gestational age infants between groups (p > .05).

CONCLUSION

Pregnancy < 12 months after bariatric surgery is associated with significantly lower mean GWG and a higher frequency of weight loss during pregnancy as well as less postpartum weight retention at 6 months. Although there were no differences birthweight, weight loss during pregnancy and its accompanying metabolic changes are concerning for a developing fetus. Further study is needed to determine the optimal timing of pregnancy after bariatric surgery with respect to both maternal and infant short and long-term outcomes.

Pre-pregnancy underweight and obesity are positively associated with small-for-gestational-age infants in a Chinese population

The association between suboptimal pre-pregnancy body mass index (BMI) and small-for-gestational-age (SGA) infants is not well defined. We investigated the association between pre-pregnancy BMI and the risk of SGA infants in a Chinese population. We performed a cohort study among 12029 mothers with a pregnancy. This cohort consisted of pregnant women that were: normal-weight (62.02%), underweight (17.09%), overweight (17.77%) and obese (3.12%). Birth sizes were reduced in the underweight and obese groups compared with the normal-weight group. Linear regression analysis indicated that birth size was positively associated with BMI in both the underweight and normal-weight groups. Further analysis showed that 12.74% of neonates were SGA infants in the underweight group, higher than 7.43% of neonates reported in the normal-weight group (adjusted RR = 1.92; 95% CI: 1.61, 2.30). Unexpectedly, 17.60% of neonates were SGA infants in the obese group, much higher than the normal-weight group (adjusted RR = 2.17; 95% CI: 1.57, 3.00). Additionally, 18.40% of neonates were large-for-gestational-age (LGA) infants in the obese group, higher than 7.26% of neonates reported in the normal-weight group (adjusted RR = 3.00; 95% CI: 2.21, 4.06). These results suggest that pre-pregnancy underweight increases the risk of SGA infants, whereas obesity increases the risks of not only LGA infants, but also SGA infants.

Rate of gestational weight gain and adverse pregnancy outcomes in rural nulliparous women: a prospective cohort analysis from China

Both inadequate and excessive gestational weight gain (GWG) have been shown to increase the risk of adverse pregnancy outcomes, but the risk profiles of GWG rate are unclear. We aimed to examine the associations between GWG rate in the second/third trimester and a spectrum of pregnancy outcomes. This study consisted of 14 219 Chinese rural nulliparous women who participated in a randomised controlled trial of prenatal micronutrient supplementation during 2006–2009. The outcomes included stillbirth, neonatal and infant death, preterm birth, macrosomia, low birth weight (LBW) and large and small for gestational age (LGA and SGA, respectively). GWG rate was divided into quintiles within each BMI category. Compared with women in the middle quintile, those in the lowest quintile had higher risks of neonatal death (adjusted OR 2·27; 95 % CI 1·03, 5·02), infant death (adjusted OR 1·85; 95 % CI 1·02, 3·37) and early preterm birth (adjusted OR 2·33; 95 % CI 1·13, 4·77), while those in the highest quintile had higher risks of overall preterm birth (adjusted OR 1·28; 95 % CI 1·04, 1·59), late preterm birth (adjusted OR 1·25; 95 % CI 1·00, 1·56), LBW (adjusted OR 1·48; 95 % CI 1·02, 2·15), macrosomia (adjusted OR 1·89; 95 % CI 1·46, 2·45) and LGA (adjusted OR 1·56; 95 % CI 1·31, 1·85). In conclusion, very low and very high GWG rates in the second/third trimester appear to be associated with adverse pregnancy outcomes in Chinese nulliparous women, indicating that an appropriate GWG rate during pregnancy is necessary for neonatal health.

[Effectiveness of mobile technology and weight gain in pregnant women in Callao, Peru]

OBJECTIVE

To evaluate the effectiveness of mobile technology in the appropriate weight gain of pregnant women.

MATERIALS AND METHODS

A quasi-experimental study. The sample included 117 pregnant women attending health facilities at la Dirección Regional de Salud (Diresa), Callao. Messages were sent to 58 pregnant women who formed the experimental group to improve their lifestyles and assistance to prenatal care (APC), while 59 pregnant women received routine education provided for pregnants. Messages were sent every three days. The nutritional status of the pregnant women was evaluated using the pre gestational BMI at the first visit of the APC. The weight gain was obtained from the difference between pre-gestational weight and weight recorded during the last controls.

RESULTS

The adequate weight gain was 27.6% of intervened pregnancies and 25.4% in the non-intervened. The 79.3% pregnant had six or more NPC in the group intervened and 54.2% in the non-intervened. The weight gain was excessive in 5.1% in the non-intervened pregnant and 1.7% in the intervened. The highest percentage of pregnant women with adequate weight gain (32.0%) was observed in the intervened pregnancies with pre-gestacional overwhegith.

CONCLUSIONS

There was no statistic difference in the use of mobile technology for a proper weight gain between both study groups. There were greater fulfillment of APC in intervened pregnancies compared to the non-intervened (p<0.05).

Relationship Between Common Mental Disorder Symptoms During Pregnancy and Preterm Birth Among Chinese Women in Wuhan

Objectives Few studies focus on the symptoms of common mental disorders during pregnancy (CMDP) and risk of preterm birth subtypes (PTB). The purpose of this study was to estimate the association between CMDP and PTB, and to examine whether or not the association between CMDP and PTB varies with the subtype of PTB in Chinese. Methods This population-based case control study, conducted in Wuhan, China, defined cases as every pregnant woman who had a PTB among all births in Wuhan, from June 10, 2011, to June 9, 2013. The same number of pregnant women who had term births was randomly selected as controls. The Electronic Perinatal Health Care Information System, a questionnaire designed for the study, provided data about the participants. Logistic regression analyses were used to model associations between CMDP and PTB, and to test associations between CMDP and two subtypes of PTB. Results The study recruited 8616 cases and an equal number of controls. We successfully collected maternal information on 6656 cases and controls for a response rate of 77.3 %. The incidence of PTB in Wuhan was 4.5 %. Spontaneous preterm births (SPTB) accounted for 60.1 %, and medically induced preterm births (IPTB) accounted for 39.9 % of preterm births. The prevalence rate of CMDP was 15.8 %. CMDP was slightly associated with PTB (crude OR 1.16, 95 % CI 1.01-1.32; adjusted OR 1.15, 95 % CI 1.00-1.32), further analyses showed CMDP was associated with IPTB (aOR 1.25, 95 % CI 1.04-1.50), but not with SPTB. Conclusion Our data suggest that CMDP is related to an increased risk of PTB, and that this association is primarily due to IPTB rather than SPTB.

Impact of Pre-Pregnancy Weight and Gestational Weight Gain on Birth Outcomes by Nativity in the United States: A Systematic Review

Background: Disparities in birth outcomes remain a problem in the United States. This study examined whether pre-pregnancy weight and gestational weight gain moderate the association between nativity and birth outcomes in the United States. Methods: We conducted a systematic review using Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines. We searched PubMED, CINAHL, PsychInfo, and Cochrane Database of Systematic Reviews for relevant articles published before May 27, 2016. Results: Four articles met the eligibility criteria by adjusting for pre-pregnancy or gestational weight gain when examining birth outcomes by nativity. Results: Results from these studies show statistically significant differences in the risk of delivering low birth weight babies between foreign-born and U.S.-born women. These differences remained after adjusting for pre-pregnancy weight or gestational weight gain. However, results stratified by nativity still vary significantly by race/ethnicity. Conclusion: Few investigations include pre-pregnancy weight and gestational weight gain when examining differences in birth outcomes by nativity. Additional studies are needed to examine possible effect modification of these weight variables on the association between nativity and birth outcomes.

Adherence to Canada's Food Guide Recommendations during Pregnancy: Nutritional Epidemiology and Public Health

Background: In Canada, pregnant women are typically referred to Canada's Food Guide (CFG), a set of national dietary recommendations designed to promote adequate nutrient intake. Pregnant women are also advised to gain weight within the Institute of Medicine guidelines, which differ by prepregnancy body mass index (BMI). However, CFG recommendations do not account for prepregnancy BMI and provide no guidance on "less healthy" (LH) foods. Objective: The aim of this study was to score women's diets according to adherence to CFG recommendations and consumption of LH foods and to examine differences between these diet scores by prepregnancy BMI. Methods: Participants enrolled in the APrON (Alberta Pregnancy Outcomes and Nutrition) prospective cohort study completed a 24-h recall in their second trimester (n = 1630). A score was created on the basis of each daily dietary CFG recommendation met, ranging from 0 to 9. The distribution of consumption (grams per day) of 8 LH food groups was given a score of 0 (none) or 1, 2, or 3 (representing the lowest, middle, or highest tertiles, respectively) and summed giving a total LH score of 0-24. Results: There were few differences in CFG recommendations met by prepregnancy BMI status, although fewer women who were overweight or obese prepregnancy met the specific recommendation to consume 7-8 servings of fruit or vegetables/d than did those who were under- or normal weight (47% and 41% compared with 50% and 54%, respectively). Although differences were small, women who were obese prepregnancy had lower CFG scores (β = -0.28; 95% CI:-0.53, -0.02) and higher LH scores (β = 0.45; 95% CI: 0.04, 0.86) than did those who were normal weight. Conclusion: The study results suggest that more attention may need to be paid to individualized counseling on dietary recommendations that take account of prepregnancy BMI.

Gestational Weight Gain in the First Two Pregnancies and Perinatal Outcomes in the Second Pregnancy

BACKGROUND

Gestational Weight Gain (GWG) below or above the Institute of Medicine (IOM) recommendations increases the risk of adverse pregnancy outcomes. However, it remains unknown whether the risk of adverse outcomes is affected by GWG in a previous pregnancy. We examined associations between GWG in the index (second) pregnancy and pregnancy outcomes, including preterm delivery and small for gestational age (SGA), while taking into consideration GWG in the first pregnancy.

METHODS

In a population-based cohort study (n = 210 564), using the Missouri maternally-linked birth registry (1989-2005), we used multivariable Poisson regression with robust error variance stratified by prepregnancy body mass index (BMI) to evaluate associations between GWG in the index pregnancy and a composite indicator of GWG in the first and second pregnancies and our outcomes of interest, after controlling for sociodemographic and pregnancy-related confounders.

RESULTS

Associations between GWG in the index pregnancy and pregnancy outcomes were moderated by GWG in the first pregnancy. Despite having GWG within recommendations in the index pregnancy, women had increased risk of preterm delivery and SGA if they had suboptimal GWG in their first pregnancy. Also, women having suboptimal GWG in the index pregnancy had increased risk of preterm delivery only if their GWG in the first pregnancy was also suboptimal.

CONCLUSIONS

The observation that women who have GWG within recommendations in a current pregnancy may still have increased risk of adverse outcomes if they had suboptimal GWG in the first pregnancy has considerable clinical and public health implications.

Geographic variability in gestational weight gain: a multilevel population-based study of women having term births in Florida (2005-2012)

PURPOSE

We examined the extent of geographic variability in gestational weight gain (GWG), identified areas where women have suboptimal GWG, and evaluated whether individual- and area-level factors account for such variability.

METHODS

We conducted a population-based cohort study including 1,385,574 women delivering term, singleton, and live births in Florida. We used a Bayesian, structured additive regression with a spatial function to analyze data from Florida's birth certificates (2005-2012) and ZIP code tabulation areas (ZCTAs; 2010 Census).

RESULTS

The prevalence of insufficient (7.7%-42.9%) and excessive (17.1%-82.4%) GWG varied widely within Florida. Geographic variability was not explained by risk factors under study. Clusters in Orlando, Tampa, and Miami exhibited increased likelihood of insufficient GWG, whereas clusters in the Northwest of Florida exhibited increased likelihood of excessive GWG.

CONCLUSIONS

We identified areas in Florida with high likelihood of suboptimal GWG that policy-makers should prioritize in the implementation of programs for optimizing GWG.

Optimal gestational weight gain: prepregnancy BMI specific influences on adverse pregnancy and infant health outcomes

OBJECTIVE

The Institute of Medicine (IOM) 2009 gestational weight gain (GWG) guidelines are based on prepregnancy body mass index (BMI) categories. We intended to refine optimal GWG for each prepregnancy BMI unit in relation to the risk of small- and large-for-gestational-age (SGA and LGA) births, cesarean section (C-section) and infant death.

STUDY DESIGN

We used data from 836,841 Ohio birth records from 2006 to 2012, and applied generalized additive models to calculate optimal GWG by prepregnancy BMI unit.

RESULTS

The suggested optimal GWG was generally similar to IOM 2009 GWG guidelines for prepregnancy BMIs <25 kg m^-2, but higher for prepregnancy BMIs 25 to 32 kg m^-2 and lower for BMIs 38 to 50 kg m^-2. The suggested optimal GWG was 14 to 18.5, 13 to 17, 11.5 to 16, 8.5 to 12.5, 4 to 10, 3 to 7, 1.5 to 6 and 1.5 to 4.5 kg for prepregnancy BMIs 15, 20, 25, 30, 35, 40, 45 and 50 kg m^-2, respectively.

CONCLUSION

This research suggests that GWG recommendations may be refined at individual prepregnancy BMI levels.

Gestational weight gain and the risk of infant mortality amongst women with normal prepregnancy BMI: the Friedmann-Balayla model

OBJECTIVE

The study of the association between gestational weight gain (GWG) and infant mortality is riddled with methodological concerns, particularly with limitations in accounting for gestational age-specific weight gain. In our study, we developed a new model, which accounts for gestational age, to determine whether insufficient or excessive GWG is associated with an increased risk of infant death amongst women with normal prepregnancy BMI (18.5-24.9 kg/m²).

METHODS

We developed and implemented the Friedmann-Balayla model to mitigate gestational age-related biases in our assessment, and conducted a population-based cohort study using the CDC's 2013 Period-Linked Birth-Infant Death data. The impact of GWG according to the 2009 IOM guidelines on the risk of infant mortality was estimated using logistic regression analysis, adjusting for relevant confounders.

RESULTS

Our cohort consisted of 1,517,525 singleton deliveries and 6138 infant deaths. Overall, relative to women achieving adequate GWG, neither women gaining insufficient nor excessive weight had greater odds of infant death during the first year of life (OR [95%CI]): 1.06 [0.97-1.17] (p = 0.174), and 0.98 [0.91-1.04] (p = 0.523), respectively. This relationship did not change when restricting our analysis to term or preterm deliveries or when conducting sensitivity analyses accounting for maternal morbidities (p > 0.05).

CONCLUSION

Using this novel analytic approach, there does not appear to be an increased risk of infant mortality if GWG falls outside of the IOM guidelines in women with normal prepregnancy BMI. Future studies should apply this methodology to other BMI categories.

The contribution of prenatal maternal factors to maternal gestational weight gain

Data from 807 mothers in Iran delivering a singleton live infant and their offspring-during the last 2 years up to August 2014-were collected from eight public health care centers and analyzed. Of the women, 46.2% gained weight within the recommended range, 29.4% had inadequate gestational weight gain (GWG), and 24.4% had excessive GWG. Excessive GWG was more common among overweight and obese women, whereas inadequate GWG was prevalent among 50% of under and normal weight women. A significant correlation was found between maternal anthropometric characteristics, folic acid intake during pregnancy, and birth order with GWG. Maternal GWG was positively correlated with neonates' weight and height.

The impact of psychosocial stressors on postpartum weight retention

Excessive gestational weight gain and postpartum weight retention are implicated in future morbidity in women. To understand whether psychosocial stressors contribute to weight retention, we used data collected in a cohort of postpartum women and analyzed measures of stress, depression, social support, and health-related quality of life. Depressive symptoms at delivery and worse health-related quality of life and lower stress at 3 months postpartum were associated with 3-month weight retention. Interventions targeting depression and improving quality of life may further reduce weight retained.

Maternal Weight Gain During Pregnancy: Comparing Methods to Address Bias Due to Length of Gestation in Epidemiological Studies

BACKGROUND

Studies examining total gestational weight gain (GWG) and outcomes associated with gestational age (GA) are potentially biased. The z-score has been proposed to mitigate this bias. We evaluated a regression-based adjustment for GA to remove the correlation between GWG and GA, and compared it to published weight-gain-for-gestational-age z-scores when applied to a study sample with different underlying population characteristics.

METHODS

Using 65 643 singleton deliveries to normal weight women at 12 US clinical sites, we simulated a null association between GWG and neonatal mortality. Logistic regression was used to estimate approximate relative risks (RR) of neonatal mortality associated with GWG, unadjusted and adjusted for GA, and the z-score, overall and within study sites. Average RRs across 5000 replicates were calculated with 95% coverage probability to indicate model bias and precision, where 95% is nominal.

RESULTS

Under a simulated null association, total GWG resulted in a biased mortality estimate (RR = 0.87; coverage = 0%); estimates adjusted for GA were unbiased (RR = 1.00; coverage = 94%). Quintile-specific RRs ranged from 0.97-1.03. Similar results were observed for site-specific analyses. The overall z-score RR was 0.97 (84% coverage) with quintile-specific RRs ranging from 0.64-0.90. Estimates were close to 1.0 at most sites, with coverage from 70-94%. Sites 1 and 6 were biased with RRs of 0.66 and 1.43, respectively, and coverage of 70% and 80%.

CONCLUSIONS

Adjusting for GA achieves unbiased estimates of the association between total GWG and neonatal mortality, providing an accessible alternative to the weight-gain-for-gestational-age z-scores without requiring assumptions concerning underlying population characteristics.

Patterns and trajectories of gestational weight gain: a prospective cohort study

BACKGROUND

Gestational weight gain in excess of or below Health Canada's guidelines is known to increase the risk of adverse outcomes for both the woman and her baby. This study describes patterns and trajectories of total and rate of gestational weight gain in a large prospective cohort of pregnant women and adolescents in the Alberta Pregnancy Outcomes and Nutrition study.

METHODS

We collected weight and height data for 1541 pregnant adolescents and women (mean age 31 years, < 27 weeks' gestation) recruited through advertisements and physicians' offices in Calgary and Edmonton between May 2009 and November 2012. Data were collected once during each trimester following enrolment and once at about 3 months post partum. The participants were categorized according to their prepregnancy body mass index (BMI) as underweight, of normal weight, overweight or obese. We calculated distributions of total and weekly rates of weight gain and determined trajectories of weight gain for each prepregnancy BMI category.

RESULTS

Of the 1541 participants, 761 (49.4%) exceeded Health Canada's guidelines for total gestational weight gain, and 272 (17.6%) gained less weight than recommended. A total of 63 (19.2%) and 38 (23.6%) participants categorized as overweight or obese, respectively, exceeded the recommended upper limit by 5 to less than 10 kg, and 53 (16.2%) and 27 (16.8%), respectively, exceeded the upper limit by at least 10 kg. Ninety-five participants (30.3%) in the overweight group and 59 (39.6%) of those in the obese group gained weight at more than double the recommended rate between the second and third trimesters. The median weight gain for participants in the normal, overweight and obese categories had exceeded recommended upper limits by about 30, 20 and 18 weeks' gestation, respectively.

INTERPRETATION

Adherence to Health Canada's guidelines for gestational weight gain was low. Excess gestational weight gain was most marked among those with a prepregnancy BMI in the overweight or obese category. The findings suggest that weight management in pregnancy is challenging and complex. Messages and supports that are tailored for women in different prepregnancy BMI categories may help to improve guideline-concordant gestational weight gain.

Maternal obesity and gestational weight gain are risk factors for infant death

OBJECTIVE

Assessment of the joint and independent relationships of gestational weight gain and prepregnancy body mass index (BMI) on risk of infant mortality was performed.

METHODS

This study used Pennsylvania linked birth-infant death records (2003-2011) from infants without anomalies born to mothers with prepregnancy BMI categorized as underweight (n = 58,973), normal weight (n = 610,118), overweight (n = 296,630), grade 1 obesity (n = 147,608), grade 2 obesity (n = 71,740), and grade 3 obesity (n = 47,277). Multivariable logistic regression models stratified by BMI category were used to estimate dose-response associations between z scores of gestational weight gain and infant death after confounder adjustment.

RESULTS

Infant mortality risk was lowest among normal-weight women and increased with rising BMI category. For all BMI groups except for grade 3 obesity, there were U-shaped associations between gestational weight gain and risk of infant death. Weight loss and very low weight gain among women with grades 1 and 2 obesity were associated with high risks of infant mortality. However, even when gestational weight gain in women with obesity was optimized, the predicted risk of infant death remained higher than that of normal-weight women.

CONCLUSIONS

Interventions aimed at substantially reducing preconception weight among women with obesity and avoiding very low or very high gestational weight gain may reduce risk of infant death.

Prevalence and characteristics associated with gestational weight gain adequacy

OBJECTIVE

To estimate the prevalence of gestational weight gain adequacy according to the 2009 Institute of Medicine recommendations and examine demographic, behavioral, psychosocial, and medical characteristics associated with inadequate and excessive gain stratified by prepregnancy body mass index (BMI) category.

METHODS

We used cross-sectional, population-based data on women delivering full-term (37 weeks of gestation or greater), singleton neonates in 28 states who participated in the 2010 or 2011 Pregnancy Risk Assessment Monitoring System. We estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for inadequate and excessive compared with adequate gain, stratified by prepregnancy BMI.

RESULTS

Overall, 20.9%, 32.0%, and 47.2% of women gained inadequate, adequate, and excessive gestational weight, respectively. Prepregnancy BMI was strongly associated with weight gain outside recommendations. Compared with normal-weight women (prevalence 51.8%), underweight women (4.2%) had decreased odds of excessive gain (adjusted OR 0.50, CI 0.40-0.61), whereas overweight and obese class I, II, and III (23.6%, 11.7%, 5.4%, and 3.5%, respectively) women had increased odds of excessive gain (adjusted OR range 2.07, CI 1.63-2.62 to adjusted OR 2.99, CI 2.63-3.40). Underweight and obese class II and III women had increased odds of inadequate gain (adjusted OR 1.25, CI 1.01-1.55 to 1.86, CI 1.45-2.36). Most characteristics associated with weight gain adequacy were demographic such as racial or ethnic minority status and education and varied by prepregnancy BMI. Notably, one behavioral characteristic-smoking cessation-was associated with excessive gain among normal-weight and obese women.

CONCLUSION

Most women gained weight outside recommendations. Understanding characteristics associated with inadequate or excessive weight gain may identify potentially at-risk women and inform much-needed interventions.

Can we safely recommend gestational weight gain below the 2009 guidelines in obese women? A systematic review and meta-analysis

A systematic review was conducted to determine the risk of adverse pregnancy outcomes with gestational weight gain (GWG) below the 2009 Institute of Medicine guidelines compared with within the guidelines in obese women. MEDLINE, Embase, Cochrane Register, CINHAL and Web of Science were searched from 1 January 2009 to 31 July 2014. Quality was assessed using a modified Newcastle-Ottawa scale. Three primary outcomes were included: preterm birth, small for gestational age (SGA) and large for gestational age (LGA). Eighteen cohort studies were included. GWG below the guidelines had higher odds of preterm birth (adjusted odds ratio [AOR] 1.46; 95% confidence interval [CI] 1.07-2.00) and SGA (AOR 1.24; 95% CI 1.13-1.36) and lower odds of LGA (AOR 0.77; 95% CI 0.73-0.81) than GWG within the guidelines. Across the three obesity classes, the odds of SGA and LGA did not show any notable gradient and remained unexplored for preterm birth. Decreased odds were noted for macrosomia (AOR 0.64; 95% CI 0.54-0.77), gestational hypertension (AOR, 0.70; 95% CI 0.53-0.93), pre-eclampsia (AOR 0.90; 95% CI 0.82-0.99) and caesarean (AOR 0.87; 95% CI 0.82-0.92). GWG below the guidelines cannot be routinely recommended but might occasionally be individualized for certain women, with caution, taking into account other known risk factors.

Comparison of gestational weight gain z-scores and traditional weight gain measures in relation to perinatal outcomes

BACKGROUND

Conventional measures of gestational weight gain (GWG) are correlated with pregnancy duration, and may induce bias to studies of GWG and perinatal outcomes. A maternal weight-gain-for-gestational-age z-score chart is a new tool that allows total GWG to be classified as a standardised z-score that is independent of gestational duration. Our objective was to compare associations with perinatal outcomes when GWG was assessed using gestational age-standardised z-scores and conventional GWG measures.

METHODS

We studied normal-weight (n=522 120) and overweight (n=237 923) women who delivered liveborn, singleton infants in Pennsylvania, 2003-11. GWG was expressed using gestational age-standardised z-scores and three traditional measures: total GWG (kg), rate of GWG (kg per week of gestation), and the GWG adequacy ratio (observed GWG/GWG recommended by the Institute of Medicine). Log-binomial regression models were used to assess associations between GWG and preterm birth, and small- and large-for-gestational-age births, while adjusting for race/ethnicity, education, smoking, and other confounders.

RESULTS

The association between GWG z-score and preterm birth was approximately U-shaped. The risk of preterm birth associated with weight gain <10th percentile of each measure was substantially overestimated when GWG was classified using total kilogram and was moderately overestimated using rate of GWG or GWG adequacy ratio. All GWG measures had similar associations with small- or large-for-gestational-age birth.

CONCLUSIONS

Our findings suggest that studies of gestational age-dependent outcomes misspecify associations if total GWG, rate of GWG, or GWG adequacy ratio are used. The potential for gestational age-related bias can be eliminated by using z-score charts to classify total GWG.

Optimizing Weight for Maternal and Infant Health - Tenable, or Too Late?

Obesity in pregnancy is the leading cause of maternal and fetal morbidity, and gestational weight gain (GWG) is one modifiable risk factor that improves pregnancy outcomes. Most pregnant women gain more than the 2009 Institute of Medicine recommendations, particularly overweight and obese women. GWG even less than the 2009 IOM guidelines in obese women may improve pregnancy outcomes and reduce large-for-gestational-age (LGA) infants, an independent risk factor for childhood obesity, without increasing small-for-gestational-age (SGA) infants. Unfortunately, despite the fact that over 50 interventional trials designed to decrease excess GWG have been conducted, these interventions have been only modestly effective, and interventions designed to facilitate weight postpartum weight loss have also been disappointing. Successful interventions are of paramount importance not only to improve pregnancy outcomes but also for the future metabolic health of the mother and her infant, and may be key in attenuating the trans-generational risk on childhood obesity.

Associations between preterm birth, low birth weight, and postpartum health in a predominantly Hispanic WIC population

OBJECTIVE

To describe the postpartum health of predominantly Hispanic participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) and identify how health characteristics differ between mothers who delivered preterm or low birth weight infants and those who did not.

DESIGN

Cross-sectional survey among postpartum WIC mothers.

SETTING

Los Angeles and Orange Counties, CA.

PARTICIPANTS

WIC participants within 1 year of delivery (n = 1,420).

MAIN OUTCOME MEASURES

Postpartum health behaviors, health characteristics, and birth spacing intentions and behaviors.

ANALYSIS

Frequencies of health characteristics were estimated using analyses with sample weights. Differences were assessed with chi-square and Fisher exact tests with Bonferroni correction for pairs of tests.

RESULTS

Many women exhibited postpartum risk factors for future adverse health events, including overweight or obesity (62.3%), depressive symptoms (27.5%), and no folic acid supplementation (65.5%). Most characteristics did not differ significantly (P > .025) between mothers of preterm infants and full-term infants or between mothers of low birth weight and normal birth weight infants.

CONCLUSIONS AND IMPLICATIONS

Despite few differences between postpartum characteristics of mothers who delivered preterm or low birth weight infants and those who did not, a high percentage of mothers had risk factors that need to be addressed. Current postpartum educational activities of WIC programs should be evaluated and shared.

Predictors of size for gestational age in St. Louis City and County

OBJECTIVE

To identify social, behavioral, and physiological risk factors associated with small for gestational age (SGA) by gestational age category in St. Louis City and County.

METHODS

A retrospective cohort study was conducted using birth certificate and fetal death records from 2000 to 2009 (n = 142,017). Adjusted associations of risk factors with SGA were explored using bivariate logistic regression. Four separate multivariable logistic regression analyses, stratified by gestational age, were conducted to estimate adjusted odds ratios.

RESULTS

Preeclampsia and inadequate weight gain contributed significantly to increased odds for SGA across all gestational age categories. The point estimates ranged from a 3.41 increased odds among women with preeclampsia and 1.76 for women with inadequate weight gain at 24-28 weeks' gestational age to 2.19 and 2.11 for full-term infants, respectively. Among full-term infants, smoking (aOR = 2.08), chronic hypertension (aOR = 1.46), and inadequate prenatal care (aOR = 1.25) had the next most robust and significant impact on SGA.

CONCLUSION

Preeclampsia and inadequate weight gain are significant risk factors for SGA, regardless of gestational age. Education on the importance of nutrition and adequate weight gain during pregnancy is vital. In this community, disparities in SGA and smoking rates are important considerations for interventions designed to improve birth outcomes.