The Impact of Maternal Predisposing Factors on Level of Maternal Serum Pregnancy-Associated Plasma Protein A and Free Subunit Human Chorionic Gonadotropin and Nuchal Translucency

Background

This study aimed to investigate the relationship between maternal predisposing factors with the level of maternal serum pregnancy-associated plasma protein A and free subunit human chorionic gonadotropin and nuchal translucency.

Materials and Methods

We performed a cross-sectional-analytical study on 762 pregnant women who referred to the Gene Azma Medical Genetics Laboratory in Isfahan for amniocentesis. All pregnant women at high risk of screening in the first trimester of pregnancy for trisomy 21 and other aneuploidy were referred to a gynecologist for amniotic fluid sampling (amniocentesis). Multiple of the means (MoM) of PAPPA ≤0.5, 0.5 ≥ MoM free β-hCG >2.5, and NT ≥3.5 mm were considered abnormal. We used Chi-square method and Mann-Whitney U-test to compare data qualitative and quantitative, respectively.

Results

In individuals with less pregnancies and deliveries, the value of abnormal NT was higher (P < 0.01, P < 0.001, respectively). On the other hand, the highest abnormal rate of NT was observed in pregnant women under 35 years (21, 84%, P < 0.012). In addition, abnormal levels of free β-hCG are more common in women < 35 years of age (186, 66.9%, P < 0.02) and female fetuses (171, 58.8%) (P < 0.006).

Conclusion

According to the results of this study, it can be said that considering the underlying factors of pregnant mothers in performing tests related to screening in the first trimester of pregnancy can lead to a reduction in false positive rates.

Perinatal effects of maternal FT3/FT4 ratio on gestational transient thyrotoxicosis

OBJECTIVE

The effects of maternal thyroid hormone levels on the course of pregnancy and birth weight have attracted interest. The aim of the present study was to consider FT3 and FT3/FT4 ratio in the evaluation of the effects of maternal thyroid functions in gestational transient thyrotoxicosis (GTT).

METHODS

This case-control study included 45 patients with GTT and 45 healthy pregnant women. Maternal history before pregnancy, thyroid function tests, thyroid autoantibodies, and thyroid ultrasonography results in 6th to 10th weeks of pregnancy were used in the differential diagnosis of GTT. In both groups, the effects of FT3, FT4 and FT3/FT4 ratios on gestational age and birth weight were evaluated.

RESULTS

There was no significant difference in the gestational age between the GTT and control groups (39,3±1,0 weeks and 39,2±1,2 weeks, respectively). Birth weights were similar in both groups (3205,2±4899 g and 3196,6±309,3 g, respectively). When maternal weight was adjusted, a positive correlation was observed between maternal FT3/FT4 ratio and birth weight (r=0,317, p=0,017). Additionally there was a positive correlation between the gestational age and the birth weight in the control group (ρ=0,726, p=0,001).

CONCLUSION

GTT had no significant effect on the gestational age and the birth weight. On the other hand an increase in the maternal FT3/FT4 ratio had a positive effect on the birth weight in the patient with GTT. Maternal characteristics (age, weight, BMI) and FT3/FT4 ratio should be taken into consideration in future impact assessment studies on this issue.

Biological changes in the pregnancy-postpartum period and subsequent cardiometabolic risk-UPSIDE MOMS: A research protocol

Multiple physiological changes occur in pregnancy as a woman's body adapts to support the growing fetus. These pregnancy-induced changes are essential for fetal growth, but the extent to which they reverse after pregnancy remains in question. For some women, physiological changes persist after pregnancy and may increase long-term cardiometabolic disease risk. The National Institutes of Health-funded study described in this protocol addresses a scientific gap by characterizing weight and biological changes during pregnancy and an extended postpartum period in relation to cardiometabolic risk. We use a longitudinal repeated measures design to prospectively examine maternal health from early pregnancy until 3 years postpartum. The aims are: (1) identify maternal weight profiles in the pregnancy-postpartum period that predict adverse cardiometabolic risk profiles three years postpartum; (2) describe immune, endocrine, and metabolic biomarker profiles in the pregnancy-postpartum period, and determine their associations with cardiometabolic risk; and (3) determine how modifiable postpartum health behaviors (diet, physical activity, breastfeeding, sleep, stress) (a) predict weight and cardiometabolic risk in the postpartum period; and (b) moderate associations between postpartum weight retention and downstream cardiometabolic risk. The proposed sample is 250 women. This study of mothers is conducted in conjunction with the Understanding Pregnancy Signals and Infant Development study, which examines child health outcomes. Biological and behavioral data are collected in each trimester and at 6, 12, 24, and 36 months postpartum. Findings will inform targeted health strategies that promote health and reduce cardiometabolic risk in childbearing women.

Higher maternal weight is related to poorer fetal autonomic function

Maternal obesity is an established risk factor for poor infant neurodevelopmental outcomes; however, the link between maternal weight and fetal development in utero is unknown. We investigated whether maternal obesity negatively influences fetal autonomic nervous system (ANS) development. Fetal heart rate variability (HRV) is an index of the ANS that is associated with neurodevelopmental outcomes in the infant. Maternal-fetal magnetocardiograms were recorded using a fetal biomagnetometer at 36 weeks (n = 46). Fetal HRV was represented by the standard deviation of sinus beat-to-beat intervals (SDNN). Maternal weight was measured at enrollment (12-20 weeks) and 36 weeks. The relationships between fetal HRV and maternal weight at both time points were modeled using adjusted ordinary least squares regression models. Higher maternal weight at enrollment and 36 weeks were associated with lower fetal HRV, an indicator of poorer ANS development. Further study is needed to better understand how maternal obesity influences fetal autonomic development and long-term neurodevelopmental outcomes.

Placental thickness in 2D prenatal ultrasonographic examination

Introduction

The placental thickness (PTh) is an ultrasonographic measurement commonly used to assess the placenta. The study aimed to determine selected factors influencing PTh in 2D prenatal ultrasonographic examination. It might have a special value in difficult cases for interpretation when PTh is above or below the reference values.

Material and methods

In this retrospective study, we analysed the results of foetal ECHO examination of 2833 foetuses performed between June 2016 and December 2019 in our single unit. 596 healthy foetuses older than 12 weeks of gestation from singleton pregnancies were enrolled in the study. The following parameters were used in the further analysis: placental implantation site, gestational age according to the last menstrual period (LMP) and foetal biometry (FB); maternal weight, height, and body mass index (BMI) at the time of examination; and PTh.

Results

PTh was affected by its location: posterior 33 mm vs. anterior 30 mm (p < 0.001). Moreover, its thickness significantly correlated with gestational age according to FB (r = 0.386, p < 0.001), LMP (r = 0.369, p < 0.001), maternal weight (r = 0.192, p < 0.001), height (r = 0.125, p = 0.002), and BMI (r = 0.147, p < 0.001), but not with maternal age (r = 0.050, p = 0.219). A linear regression model based on these data explained the 16.38% variability of the tested subjects (p < 0.001).

Conclusions

Our observations suggest that maternal weight correlated more strongly with PTh than maternal BMI. For PTh evaluation, it is important to pay attention to the placental implantation site - the posterior placenta was thicker than the anterior placenta. Moreover, PTh variability remains largely unknown; therefore, further research in this field is needed.

Changes in Retinol Binding Protein 4 Level in Undernourished Children After a Nutrition Intervention Are Positively Associated With Mother's Weight but Negatively With Mother's Height, Intake of Whole Milk, and Markers of Systemic Inflammation: Results From a Community-Based Intervention Study

Background:

The changes of plasma retinol binding protein 4 (RBP4) level after a nutrition intervention can indicate the metabolic changes associated with the delivered intervention.

Objective:

We investigated the changes in plasma RBP4 level among 12- to 18-month-old children after a nutrition intervention and measured its association with subcutaneous adiposity, maternal characteristics, and inflammation.

Methods:

Data of 520 undernourished children (250 of them had length-for-age Z score [LAZ] <−1 to −2 and 270 had LAZ score <−2) were collected from the Bangladesh Environmental Enteric Dysfunction study conducted in Dhaka, Bangladesh. Multivariable linear regression and generalized estimation equations (GEE) modeling techniques were used to measure the association.

Results:

At baseline, median RBP4 level was 19.9 mg/L (interquartile range [IQR]: 7.96), and at the end of the intervention, it was 20.6 mg/L (IQR: 9.06). Percentage changes in plasma RBP4 level were not significantly associated (P > .05) with the percentage changes in child’s height, weight, and subcutaneous adiposity. But maternal height (regression coefficient, β = −1.62, P = .002) and milk intake (β = −0.05, P = .01) were negatively and maternal weight was positively associated (β = 0.56, P = .03) with the changes in RBP4 levels. The GEE models revealed negative association of RBP4 levels with C-reactive protein (CRP; β = −0.14, P < .05) and α-1-acid glycoprotein (AGP; β = −0.03, P < .05).

Conclusion:

Children whose mothers were taller experienced less increase in plasma RBP4 level, and children whose mothers had a higher weight experienced more increase in the RBP4 level from baseline. We have also found that CRP and AGP levels and intake of whole milk were negatively associated with the plasma RBP4 level.

Relationships Among Factors Related to Childbirth and Breastfeeding Outcomes in Primiparous Women

OBJECTIVES

To explore the relationships among potentially modifiable factors related to childbirth and effective breastfeeding initiation at approximately 36 hours after birth and duration and exclusivity at hospital discharge, 2 weeks, 2 months, and 6 months after birth in primiparous women and to explore whether modifiable and nonmodifiable secondary factors and covariates influenced the relationships among factors related to childbirth and these breastfeeding outcomes.

DESIGN

A prospective, longitudinal, cohort study.

SETTING

The postpartum units of two general hospitals in eastern Canada.

PARTICIPANTS

Ninety-seven mother-infant dyads.

METHODS

We recorded demographic, childbirth, obstetric history, and breastfeeding data through chart review. A breastfeeding observation was completed at approximately 36 hours after birth by unit nurses. Participants maintained breastfeeding logs in hospital and for 6 months after birth and completed three self-report questionnaires before discharge. We analyzed outcomes using backward stepwise linear and logistic regression.

RESULTS

One childbirth factor, labor induced with oxytocin, was negatively associated with effective initiation of breastfeeding, and none was related to breastfeeding duration and exclusivity at any time point. Maternal weight; professional support; and newborn's gestational age at birth, 5-minute Apgar score, weight loss, LATCH score, and active feeds (newborn actively suckled at the breast) were significantly associated with breastfeeding outcomes.

CONCLUSION

Induction of labor with oxytocin should be used judiciously; when used, nurses must be hypervigilant to assess the mother-infant dyad for breastfeeding issues and to intervene to prevent or remediate them.

Maternal stature, maternal education and child growth in Pakistan: a cross-sectional study

Pakistan has a significantly higher prevalence of stunted children under five years old compared with other countries with a similar income level. Given maternal education is a modifiable factor, we analyzed whether education has a larger marginal effect on improving children's growth for shorter stature mothers. Pakistan Demographic and Health Survey of 2012–13 was analyzed, with a total of 3,883 of children under five years of age (belonged to 2,327 mothers). The results showed that the overall prevalence of stunting, underweight, wasting, and overweight in our sample was 45%, 26.2%, 9.9%, and 9.5%, respectively. Short stature mothers have a higher number of malnourished children as compared to taller mothers. Compared to tall stature mothers, short stature mothers at all education levels have a higher number of stunted and underweight children. Maternal education has a significant positive effect on children's growth. However, we did not find significant differences in the marginal effect of maternal education among mothers with different statures. Policies providing specialized care to children born to short stature mothers are crucial, along with emphasizing mothers' education. Moreover, a poverty elevation program is necessary as a significant fraction of childhood malnutrition is attributed to the wealth index.

Does exercise during pregnancy impact on maternal weight gain and fetal cardiac function? A randomized controlled trial

OBJECTIVE

To evaluate the association between physical exercise during pregnancy and maternal gestational weight gain and fetal cardiac function.

METHODS

This was a randomized controlled trial of women with a singleton pregnancy managed from the first trimester at the Hospital de Torrejón, Madrid, between November 2014 and June 2015. Women were randomized to either follow a supervised physical conditioning program, consisting of a 60-min session 3 days per week for the duration of pregnancy, or not attend any exercise program (controls). The primary outcome was maternal weight gain during pregnancy. Secondary outcomes included fetal cardiac function parameters evaluated at 20, 28 and 36 weeks' gestation, Cesarean section, preterm delivery, induction of labor and birth weight. A sample size of 45 in each group was planned to detect differences in maternal weight gain of at least 1 kg, with a power of > 80% and α of 0.05.

RESULTS

During the study period, 120 women were randomized into the exercise (n = 75) and control (n = 45) groups. Following exclusions, the final cohort consisted of 42 women in the exercise group and 43 in the control group. Baseline characteristics (maternal age, prepregnancy body mass index, parity, conception by in-vitro fertilization, Caucasian ethnicity, physical exercise prior to pregnancy and smoker) were similar between the two groups. No differences were found between the groups in maternal weight at 20, 28, 36 and 38 weeks' gestation or in weight gain at 38 weeks. However, the proportion of women with weight loss ≥ 9 kg at 6 weeks postpartum was higher in the exercise compared with the control group (68.2% vs 42.8%; relative risk 1.593; P = 0.02). The ductus arteriosus pulsatility index (DA-PI) at 20 weeks (2.43 ± 0.40 vs 2.26 ± 0.33, P < 0.05) and the ejection fraction (EF) at 36 weeks (0.85 ± 0.13 vs 0.81 ± 0.11, P < 0.05) were higher in the exercise compared with the control group. All other evaluated fetal cardiac function parameters were similar between the two groups.

CONCLUSIONS

Performing exercise during pregnancy is not associated with a reduction in maternal weight gain but increases weight loss at 6 weeks postpartum. Physical exercise during pregnancy is associated with increased fetal DA-PI at 20 weeks and EF at 36 weeks, which could reflect adaptive mechanisms. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Fetal fraction-based risk algorithm for non-invasive prenatal testing: screening for trisomies 13 and 18 and triploidy in women with low cell-free fetal DNA

OBJECTIVE

To identify pregnancies at increased risk for trisomy 13, trisomy 18 or triploidy attributable to low fetal fraction (FF).

METHODS

A FF-based risk (FFBR) model was built using data from more than 165 000 singleton pregnancies referred for single-nucleotide polymorphism (SNP)-based non-invasive prenatal testing (NIPT). Based on maternal weight and gestational age (GA), FF distributions for normal, trisomy 13, trisomy 18 and triploid pregnancies were constructed and used to adjust prior risks for these abnormalities. A risk cut-off of ≥ 1% was chosen to define pregnancies at high risk for trisomy 13, trisomy 18 or triploidy (high FFBR score). The model was evaluated on an independent blinded set of pregnancies for which SNP-based NIPT did not return a result, and for which pregnancy outcome information was gathered retrospectively.

RESULTS

The evaluation cohort comprised 1148 cases, of which approximately half received a high FFBR score. Compared with rates expected based on maternal age (MA) and GA, cases with a high FFBR score had a significantly increased rate of trisomy 13, trisomy 18 or triploidy combined (5.7% vs 0.7%; P < 0.001) and also of unexplained pregnancy loss (14.7% vs 10.4%; P < 0.001). For cases that did not receive a high FFBR score, the incidence of a chromosomal abnormality or pregnancy loss was not significantly different from that expected based on MA and GA. In this study cohort, the sensitivity of the FFBR model for detection of trisomy 13, trisomy 18 or triploidy was 91.4% (95% CI, 76.9-98.2%) with a positive predictive value of 5.7% (32/564; 95% CI, 3.9-7.9%).

CONCLUSIONS

For pregnancies with a FF too low to receive a result on standard NIPT, the FFBR algorithm identified a subset of cases at increased risk for trisomy 13, trisomy 18 or triploidy. For the remainder of cases, the risk of a fetal chromosomal abnormality was unchanged from that expected based on MA and GA. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Birth risks according to maternal height and weight - an analysis of the German Perinatal Survey

Objective To investigate the variability in the prevalences of selected birth risks in women of different heights and weights. Methods Data from the German Perinatal Survey of 1998-2000 were analyzed: 503,468 cases contributed to our analysis of the prevalences of selected birth risks specified according to maternal weight groups, 502,562 cases contributed to our analysis according to maternal height groups and 43,928 cases contributed to our analysis of birth risks in women with a body mass index (BMI) of 21-23 kg/m2 but different heights and weights. Data analysis was performed using SPSS version 22. Results Some birth risks varied substantially by maternal height in women with a "normal" BMI of 21-23 kg/m2: the prevalence of post-term birth increased from 8.7% in women with a height of 150 cm to 13.5% in 185 cm tall women, the prevalence of preterm birth decreased from 5.9% (150 cm tall women) to 3.1% (185 cm tall women), a pathologic cardiotocography (CTG) or poor fetal heart sounds on auscultation occurred in 19.4% of the 150 cm tall women but only in 9.2% of 185 cm tall women and cephalopelvic disproportion decreased from 12.3% (150 cm tall women) to 1.2% (185 cm tall women). Analyses of women in different body height and weight groups (without restriction of BMI) likewise showed differences in the prevalences of some birth risks. Conclusion Birth risks may vary by height and weight in women with the same, "normal" BMI. BMI should not be the only way by which the impact of maternal height and weight is assessed with regard to perinatal outcomes such as birth risks.

Relationship Between Maternal Pre-pregnancy Weight and Offspring Weight Strengthens as Children Develop: A Population-Based Retrospective Cohort Study

Background

Maternal pre-pregnancy weight has been reported to be positively associated with offspring weight. The association between maternal weight and offspring weight might be explained by maternal lifestyle. We investigated the strength of the relationship between maternal body mass index (BMI) at the beginning of pregnancy and offspring BMI at several growth stages.

Methods

The source population was all eighth graders registered in all public schools in the city of Fukuroi, Japan, in 2012. Records of maternal anthropometry at the beginning of pregnancy were obtained from the Maternal and Child Health (MCH) Handbook. The height and body weight of each student were measured. A regression model was used to assess the association between maternal BMI z-score at the beginning of pregnancy and offspring BMI z-score at various ages.

Results

Of the source population, data from the MCH Handbook were obtained for 480 students. Among males, maternal BMI z-score was not associated with offspring BMI z-score at birth and at age 3 years but was associated with offspring BMI z-score at age 13 years (standardized regression coefficient (β) = 0.19; P < 0.01). Among females, maternal BMI z-score was associated with offspring BMI z-score at birth (β = 0.11; P < 0.05), at age 3 years (β = 0.22; P < 0.01) and at age 13 years (β = 0.51; P < 0.01).

Conclusions

Our results suggest that the positive association between maternal weight at the beginning of pregnancy and offspring weight around puberty is stronger than that between maternal weight and offspring weight at birth. Maternal lifestyle may influence offspring weight in adolescence.

Maternal underweight and obesity and risk of orofacial clefts in a large international consortium of population-based studies

Background

Evidence on association of maternal pre-pregnancy weight with risk of orofacial clefts is inconsistent.

Methods

Six large case-control studies of orofacial clefts from Northern Europe and the USA were included in analyses pooling individual-level data. Cases included 4943 mothers of children with orofacial clefts (cleft lip only: 1135, cleft palate with cleft lip: 2081, cleft palate only: 1727) and controls included 10 592 mothers of unaffected children. Association of orofacial cleft risk with pre-pregnancy maternal weight classified by level of body mass index (BMI, kg/m 2 ) was evaluated using logistic regression adjusting for multiple covariates.

Results

Cleft palate, both alone and with cleft lip (CP+/-CL), was associated with maternal class II+ pre-pregnancy obesity (≥ 35)compared with normal weight [adjusted odds ratio (aOR) = 1.36; 95% confidence interval (CI) = 1.16, 1.58]. CP+/-CL was marginally associated with maternal underweight (aOR = 1.16; 95% CI = 0.98, 1.36). Cleft lip alone was not associated with BMI.

Conclusions

In this largest population-based study to date, we found an increased risk of cleft palate, with or without cleft lip, in class II+ obese mothers compared with normal-weight mothers; underweight mothers may also have an increased risk, but this requires further study. These results also suggest that extremes of weight may have a specific effect on palatal development.

Maternal pre-pregnancy obesity and child neurodevelopmental outcomes: a meta-analysis

This review examined evidence of the association between maternal pre-pregnancy overweight/obesity status and child neurodevelopmental outcomes. PubMed and PsycINFO databases were systematically searched for empirical studies published before April 2017 using keywords related to prenatal obesity and children's neurodevelopment. Of 1483 identified papers, 41 were included in the systematic review, and 32 articles representing 36 cohorts were included in the meta-analysis. Findings indicated that compared with children of normal weight mothers, children whose mothers were overweight or obese prior to pregnancy were at increased risk for compromised neurodevelopmental outcomes (overweight: OR = 1.17, 95% CI [1.11, 1.24], I²  = 65.51; obese: OR = 1.51; 95% CI [1.35, 1.69], I²  = 79.63). Pre-pregnancy obesity increased the risk of attention deficit-hyperactivity disorder (OR = 1.62; 95% CI [1.23, 2.14], I²  = 70.15), autism spectrum disorder (OR = 1.36; 95% CI [1.08, 1.70], I²  = 60.52), developmental delay (OR = 1.58; 95% CI [1.39, 1.79], I²  = 75.77) and emotional/behavioural problems (OR = 1.42; 95% CI [1.26, 1.59], I²  = 87.74). Given the current obesity prevalence among young adults and women of childbearing age, this association between maternal obesity during pregnancy and atypical child neurodevelopment represents a potentially high public health burden.

The effect of progesterone use in the first trimester on fetal nuchal translucency

Objective:

To evaluate the possible association between progesterone use in the first trimester of pregnancy and fetal nuchal translucency (NT).

Material and Methods:

This is an observational case-control study, which was conducted with patients who underwent nuchal scans between March 2015 and February 2016 and consequently delivered live and healthy babies. The study group was composed of assisted reproductive technology pregnancies and used intravaginal progesterone 180 mg/day until gestational week 12. The control group comprised pregnant women who became pregnant spontaneously without using any progesterone preparation in the first trimester.

Results:

One hundred sixty-four (57.5%) of 285 patients were in the control group and 121 (42.5%) were in the progesterone group. Age, bodyweight, gravidity, and parity number of previous births and abortus, gestational week, crown-rump lengths, free β-human chorionic gonadotropin, pregnancy-associated plasma protein A, and NT values of the progesterone and control groups were recorded and we investigated whether there was a statistically significant difference between the two groups in terms of these parameters; maternal weight was found to be higher in the progesterone group than in the control group and the difference between the groups was statistically significant (p=0.019 and p=0.025). Whether the difference in NT was caused by the effect of maternal weight was investigated using the covariance analysis test and maternal weight was not found to be statistically significant in the model (p=0.284).

Conclusion:

Fetal NT was increased in the progesterone group compared with the untreated group in healthy pregnancies.

A new customized fetal growth standard for African American women: the PRB/NICHD Detroit study

BACKGROUND

The assessment of fetal growth disorders requires a standard. Current nomograms for the assessment of fetal growth in African American women have been derived either from neonatal (rather than fetal) biometry data or have not been customized for maternal ethnicity, weight, height, and parity and fetal sex.

OBJECTIVE

We sought to (1) develop a new customized fetal growth standard for African American mothers; and (2) compare such a standard to 3 existing standards for the classification of fetuses as small (SGA) or large (LGA) for gestational age.

STUDY DESIGN

A retrospective cohort study included 4183 women (4001 African American and 182 Caucasian) from the Detroit metropolitan area who underwent ultrasound examinations between 14-40 weeks of gestation (the median number of scans per pregnancy was 5, interquartile range 3-7) and for whom relevant covariate data were available. Longitudinal quantile regression was used to build models defining the "normal" estimated fetal weight (EFW) centiles for gestational age in African American women, adjusted for maternal height, weight, and parity and fetal sex, and excluding pathologic factors with a significant effect on fetal weight. The resulting Perinatology Research Branch/Eunice Kennedy Shriver National Institute of Child Health and Human Development (hereinafter, PRB/NICHD) growth standard was compared to 3 other existing standards--the customized gestation-related optimal weight (GROW) standard; the Eunice Kennedy Shriver National Institute of Child Health and Human Development (hereinafter, NICHD) African American standard; and the multinational World Health Organization (WHO) standard--utilized to screen fetuses for SGA (<10th centile) or LGA (>90th centile) based on the last available ultrasound examination for each pregnancy.

RESULTS

First, the mean birthweight at 40 weeks was 133 g higher for neonates born to Caucasian than to African American mothers and 150 g higher for male than female neonates; maternal weight, height, and parity had a positive effect on birthweight. Second, analysis of longitudinal EFW revealed the following features of fetal growth: (1) all weight centiles were about 2% higher for male than for female fetuses; (2) maternal height had a positive effect on EFW, with larger fetuses being affected more (2% increase in the 95th centile of weight for each 10-cm increase in height); and (3) maternal weight and parity had a positive effect on EFW that increased with gestation and varied among the weight centiles. Third, the screen-positive rate for SGA was 7.2% for the NICHD African American standard, 12.3% for the GROW standard, 13% for the WHO standard customized by fetal sex, and 14.4% for the PRB/NICHD customized standard. For all standards, the screen-positive rate for SGA was at least 2-fold higher among fetuses delivered preterm than at term. Fourth, the screen-positive rate for LGA was 8.7% for the GROW standard, 9.2% for the PRB/NICHD customized standard, 10.8% for the WHO standard customized by fetal sex, and 12.3% for the NICHD African American standard. Finally, the highest overall agreement among standards was between the GROW and PRB/NICHD customized standards (Cohen's interrater agreement, kappa = 0.85).

CONCLUSION

We developed a novel customized PRB/NICHD fetal growth standard from fetal data in an African American population without assuming proportionality of the effects of covariates, and without assuming that these effects are equal on all centiles of weight; we also provide an easy-to-use centile calculator. This standard classified more fetuses as being at risk for SGA compared to existing standards, especially among fetuses delivered preterm, but classified about the same number of LGA. The comparison among the 4 growth standards also revealed that the most important factor determining agreement among standards is whether they account for the same factors known to affect fetal growth.

Systematic Review of the Methodological Quality of Studies Aimed at Creating Gestational Weight Gain Charts

A range of adverse outcomes is associated with insufficient and excessive maternal weight gain in pregnancy, but there is no consensus regarding what constitutes optimal gestational weight gain (GWG). Differences in the methodological quality of GWG studies may explain the varying chart recommendations. The goal of this systematic review was to evaluate the methodological quality of studies that aimed to create GWG charts by scoring them against a set of predefined, independently agreed-upon criteria. These criteria were divided into 3 domains: study design (12 criteria), statistical methods (7 criteria), and reporting methods (4 criteria). The criteria were broken down further into items, and studies were assigned a quality score (QS) based on these criteria. For each item, studies were scored as either high (score = 0) or low (score = 1) risk of bias; a high QS correlated with a low risk of bias. The maximum possible QS was 34. The systematic search identified 12 eligible studies involving 2,268,556 women from 9 countries; their QSs ranged from 9 (26%) to 29 (85%) (median, 18; 53%). The most common sources for bias were found in study designs (i.e., not prospective); assessments of prepregnancy weight and gestational age; descriptions of weighing protocols; sample size calculations; and the multiple measurements taken at each visit. There is wide variation in the methodological quality of GWG studies constructing charts. High-quality studies are needed to guide future clinical recommendations. We recommend the following main requirements for future studies: prospective design, reliable evaluation of prepregnancy weight and gestational age, detailed description of measurement procedures and protocols, description of sample-size calculation, and the creation of smooth centile charts or z scores.

Relationships between maternal overweight prior to pregnancy, feeding mode and infant feeding beliefs and practices

AIM

This study aimed to examine whether pre-pregnancy weight status was associated with maternal feeding beliefs and practices in the early post-partum period.

METHODS

This study uses secondary analysis of longitudinal data from Australian mothers. Participants (n = 486) were divided into two weight status groups based on self-reported pre-pregnancy weight and measured height: healthy weight (body mass index (BMI) <25 kg/m(2) ; n = 321) and overweight (BMI > 25 kg/m(2) ; n = 165). Feeding beliefs and practices were self-reported via an established questionnaire that assessed concerns about infant overeating and undereating, awareness of infant cues, feeding to a schedule and using food to calm.

RESULTS

Infants of overweight mothers were more likely to have been given solid foods in the previous 24 h (29% vs. 20%) and fewer were fully breastfed (50% vs. 64%). Multivariable regression analyses (adjusted for maternal education, parity, average infant weekly weight gain, feeding mode and introduction of solids) revealed that pre-pregnancy weight status was not associated with using food to calm, concern about undereating, awareness of infant cues or feeding to a schedule. However, feeding mode was associated with feeding beliefs and practices.

CONCLUSIONS

Although no evidence for a relationship between maternal weight status and early maternal feeding beliefs and practices was observed, differences in feeding mode and early introduction of solids were observed. The emergence of a relationship between feeding practices and maternal weight status may occur when the children are older, solid feeding is established and they become more independent in feeding.

Relation between low 50-g glucose challenge test results and small-for-gestational-age infants

AIM

There is no consensus opinion regarding a possible relation between low 50-g glucose challenge test (GCT) results and small-for-gestational-age infants (SGA). This study aimed to clarify the relation between low 50-g GCT results and SGA, after adjusting for potential confounding factors, using a large clinical dataset.

MATERIAL AND METHODS

Our retrospective cohort study evaluated the obstetric records of women who delivered at Kofu Municipal Hospital (Japan) between January 2011 and December 2013. The exclusion criteria were gestational diabetes mellitus, diabetes in pregnancy, and GCT results of ≥140 mg/dL. Based on these criteria, we included 1603 women who had undergone a GCT between 24 and 28 weeks of gestation, and divided the subjects into a low-GCT group (≤90 mg/dL) and a non-low-GCT group (91-139 mg/dL). The χ(2) -test and multivariate logistic regression analysis were used to investigate the association between low GCT results and SGA.

RESULTS

The mean subject age was 30.4 ± 5.4 years, with 45.1% nulliparity (n = 723) and 1538 (96.0%) term deliveries. The incidence of SGA was 10.7% (172/1603), and 17.9% (287/1603) of the women had low GCT results. Low GCT results were significantly associated with an increased risk of SGA (odds ratio, 1.66; 95% confidence interval, 1.14-2.42), after controlling for maternal age, pre-pregnancy maternal weight, maternal weight gain during pregnancy, and pregnancy-induced hypertension.

CONCLUSION

It appears that there is a significant association between low GCT results and SGA. However, further studies are needed to explore the detailed mechanisms of this association.

Contribution of prepregnancy body mass index and gestational weight gain to adverse neonatal outcomes: population attributable fractions for Canada

BACKGROUND

Low or high prepregnancy body mass index (BMI) and inadequate or excess gestational weight gain (GWG) are associated with adverse neonatal outcomes. This study estimates the contribution of these risk factors to preterm births (PTBs), small-for-gestational age (SGA) and large-for-gestational age (LGA) births in Canada compared to the contribution of prenatal smoking, a recognized perinatal risk factor.

METHODS

We analyzed data from the Canadian Maternity Experiences Survey. A sample of 5,930 women who had a singleton live birth in 2005-2006 was weighted to a nationally representative population of 71,200 women. From adjusted odds ratios, we calculated population attributable fractions to estimate the contribution of BMI, GWG and prenatal smoking to PTB, SGA and LGA infants overall and across four obstetric groups.

RESULTS

Overall, 6% of women were underweight (<18.5 kg/m(2)) and 34.4% were overweight or obese (≥25.0 kg/m(2)). More than half (59.4%) gained above the recommended weight for their BMI, 18.6% gained less than the recommended weight and 10.4% smoked prenatally. Excess GWG contributed more to adverse outcomes than BMI, contributing to 18.2% of PTB and 15.9% of LGA. Although the distribution of BMI and GWG was similar across obstetric groups, their impact was greater among primigravid women and multigravid women without a previous PTB or pregnancy loss. The contributions of BMI and GWG to PTB and SGA exceeded that of prenatal smoking.

CONCLUSIONS

Maternal weight, and GWG in particular, contributes significantly to the occurrence of adverse neonatal outcomes in Canada. Indeed, this contribution exceeds that of prenatal smoking for PTB and SGA, highlighting its public health importance.

Non-invasive prenatal testing for fetal aneuploidies in the first trimester of pregnancy

OBJECTIVES

To evaluate the feasibility of non-invasive prenatal testing (NIPT) of maternal plasma samples collected from pregnant Chinese women in early gestation, between 8 + 0 and 12 + 6 weeks' gestation.

METHODS

In this pilot study, 212 women with high-risk pregnancies were recruited at a single Chinese Hospital. Fetal aneuploidies associated with chromosomes 21, 18, 13, X and Y were detected by massively parallel sequencing of maternal plasma DNA samples. Invasive prenatal diagnosis by either chorionic villus sampling or amniocentesis and then karyotyping was offered to all women to confirm both positive and negative NIPT results. Fetal DNA fraction was also determined in male pregnancies, by the relative percentage of Y-chromosome sequences. All confirmed NIPT-negative pregnancies were followed up to birth and neonates were clinically evaluated for any symptoms of chromosomal disease.

RESULTS

Autosomal aneuploidies trisomy 21 (n = 2), 18 (n = 1) and 13 (n = 1) were detected by NIPT and confirmed by amniocentesis and karyotyping. There were one false-positive 45,X sample and two false-negative samples associated with fetal karyotypes 47,XXY and 45,X[16]/47,XXX[14]. In the 100 male pregnancies, the median fetal DNA fraction was 8.54% and there was a trend towards an increasing fetal fraction from 8 + 0 to 12 + 6 weeks' gestation. The majority (95%) of pregnancies had a fetal DNA fraction > 4%, which is generally the limit for accurate aneuploidy detection by NIPT. Across this early gestational time period, there was a weak inverse relationship (R(2)  = 0.186) between fetal DNA fraction and maternal weight.

CONCLUSIONS

NIPT is highly reliable and accurate when applied to maternal DNA samples collected from pregnant women in the first trimester between 8 + 0 and 12 + 6 weeks.

Adherence to breastfeeding guidelines and maternal weight 6 years after delivery

OBJECTIVES

There is a dearth of information on the long-term maternal effects of breastfeeding. The objective of this study was to examine adherence to breastfeeding recommendations of exclusive breastfeeding for ≥4 months and continuation of breastfeeding for ≥1 year and maternal weight retention 6 years after delivery.

METHODS

Using data from the Infant Feeding Practices Study II (IFPS II), we categorized women by the degree to which they met breastfeeding recommendations. Mothers' self-reported weight 6 years after delivery (IFPS Year 6 Follow-Up) was compared with self-reported prepregnancy weight from IFPS II. Using linear regression models, adjusting for covariates, we examined associations between breastfeeding recommendation adherence and weight retention.

RESULTS

Of the 726 women in our study, 17.9% never breastfed. Among those who initiated breastfeeding, 29.0% breastfed exclusively for ≥4 months, and 20.3% breastfed exclusively for ≥4 months and continued breastfeeding for ≥12 months. Prepregnancy BMI modified the association between breastfeeding recommendation adherence and weight retention. Adjusting for covariates, we found no association between breastfeeding recommendations adherence and weight retention among normal and overweight mothers. Among obese mothers, there was a significant linear trend (P = .03), suggesting that those who fully adhered to breastfeeding recommendations retained less weight (-8.0 kg) than obese women who never breastfed.

CONCLUSIONS

This study suggests that improving adherence to breastfeeding recommendations may help reduce long-term maternal weight retention among obese mothers. Larger studies, with diverse populations and similar longitudinal designs, are needed to explore this relationship.

Increasing prevalence of macrosomia in Flanders, Belgium: an indicator of population health and a burden for the future

Macrosomia, defined as birth weight > 4 kg, increased in Flanders from 7.3% (4899/67143) in 1991 to 8.63% (6034/69924) in 2010 (p < 0.0001) in singleton pregnancies at term. There are at least 3 important factors contributing to this evolution. (1) Increase of maternal stature and length: during the last century, mean length of Belgian women increased with approximately 10cm to the current value of 1.66 m. (2) Increase of maternal age: the proportion of pregnant women aged 35 years or more increased significantly from 6.1% in 1991 to 14.3% in 2010. (3) Increase of maternal overweight or obesity: between 1994 and 2000, there was an increase of 4% for both overweight and obesity in women and today, 44% of Belgians are overweight (BMI > 25 kg/m²), and 12% are obese (BMI > 30 kg/m²). From these data, rate and increase of macrosomia can be -considered indirect indicators of general public health. Next to the risks for obstetrical complications, neonates > 4 kg are at risk for development of adult obesity and type 2 diabetes with related diseases, such as hypertension and metabolic syndrome. As adults, they also tend to deliver macrosomic baby's themselves. As such, macrosomia at birth is a burden for a community's future health status, health care and related costs. Prenatal health care workers should be aware of the relevance to prevent macrosomia in the first generation by -implementing guidelines on nutrition, physical activity and appropriate weight gain into routine preconceptional and prenatal care, screening for gestational diabetes with strict monitoring of blood sugar levels in affected -individuals, and promotion of breastfeeding.

Physical characteristics of the environment and BMI of young urban children and their mothers

The study examined whether characteristics of the urban physical environment are associated with child and maternal body mass index (BMI) in a sample of 3 year-old children and their mothers from 18 US cities (N=1997 dyads). BMI was determined based on measured height and weight. Characteristics of the interior and exterior physical environment, assessed and rated by trained interviewers, were related to child BMI at age 3 and to their mother's BMI. Negative aspects of the physical environment were more strongly related to maternal BMI among whites than among African-Americans or Hispanics.