Somatic development at birth as influenced by maternal characteristics - an analysis of the German Perinatal Survey

Association between prenatal PM2.5 exposure and the risk of large for gestational age

BACKGROUND

The relationship between particulate matter <2.5 µm (PM2.5) and large for gestational age (LGA) is unclear, and studies conducted in highly polluted areas are lacking. We aimed to explore the association between PM2.5 and the risk of LGA in China.

METHODS

Maternal and neonatal characteristics were collected in the National Prepregnancy Examination Project. The definition of LGA was neonates with a weight over the 90th percentile for gestational age. Logistic regression was used to evaluate the relationship between PM2.5 exposure and the risk of LGA. The dose-response relationship was evaluated using a restricted cubic spline model.

RESULTS

There were 196,243 mother-neonate pairs included, among which the percentage of LGA was 15.3%. The average PM2.5 concentration was 75.29 µg/m³. A 10 µg/m³ increase in PM2.5 during the whole pregnancy was associated with an increased risk of LGA (odds ratio (OR) 1.097, 95% confidence interval (CI) 1.091-1.103). Pregnant women in the high-exposure group had a higher risk of giving birth to an LGA infant (OR 1.37, 95% CI 1.33-1.41). There was a nonlinear relationship between PM2.5 concentration and the risk of LGA, and the risk increased more rapidly at higher PM2.5 levels.

CONCLUSIONS

Prenatal exposure to PM2.5 was linked to an increased risk of LGA.

IMPACT

A nation-wide study in a highly polluted country suggested the association between prenatal PM2.5 exposure and LGA. A trimester-specific relationship between PM2.5 exposure and LGA was established. Call for attention on the pregnant women in highly polluted areas who were in high risk of giving birth to LGA.

Impact of maternal height on birthweight classification in singleton births at term: a cohort study in The Netherlands

OBJECTIVE

To assess the association between maternal height and birthweight in a healthy population and to study the effect of maternal height on the classification of birthweight as small for gestational age (SGA) and large for gestational age (LGA).

METHODS

A descriptive, observational retrospective study was conducted in a low risk population in the Netherlands. The study included term singleton healthy nonsmoking pregnant women with normal body mass index (n = 9291). We calculated the impact of maternal height on birthweight using multiple linear regression analyses with adjustment for gestational age, gender, and parity. We calculated the number of newborns classified as SGA and LGA using the cutoff point of the Dutch Birthweight chart, which does not customize for maternal height. Subsequently, we calculated the changes in classification from SGA and LGA to appropriate for gestational age (AGA) in case of customization for maternal height.

RESULTS

A significant association was found between maternal height and birthweight; 15.0 g higher birthweight per extra cm maternal height (95% confidence interval 13.8-16.1; p<.001; R² model = 0.28). The incidence of SGA was 7.1% (range 17.4-2.0% form shortest to tallest maternal height category) and of LGA 8.4% (range 1.9-21.5% from shortest to tallest maternal height category). We calculated a shift in classification: 114 newborns (17.3%) in shorter (<167 cm) women previously SGA and 165 newborns (21.1%) in taller (>173 cm) women previously LGA were classified as AGA when controlling for maternal height.

CONCLUSIONS

Maternal height is significantly associated with birthweight. Birthweight charts customized for maternal height change classification in one out of six SGA or LGA newborns at term.

Impact of maternal height and gestational diabetes mellitus on offspring birthweight

AIMS

To evaluate the impact of gestational diabetes mellitus (GDM) and maternal height on offspring birthweight.

METHODS

This is an observational cohort study, encompassing 4 111 Finnish primiparous women from Vantaa city, Finland, with singleton deliveries between 2009 and 2015. Data were obtained from the Finnish Medical Birth Register. The study population was divided into five groups according to maternal height. Cut-offs for height levels were I ≤ 158 cm, II 159-163 cm, III 164-167 cm, IV 168-172 cm, V ≥ 173 cm. The main outcome measure was offspring birthweight, expressed as Z-scores according to sex and gestational age.

RESULTS

Independently, both maternal height and GDM increased offspring birthweight (p < 0.001 for height and GDM). When studying the interaction, a significant increase in offspring birthweight was noted only in extreme height categories; group I ≤ 158 cm (p = 0.011), group IV 168-172 cm (p = 0.010) and group V ≥ 173 cm (p < 0.001) and the impact was similar in both sexes. Maternal height had no impact on offspring ponderal index (p = 0.20 for trend).

CONCLUSIONS

In extreme height categories, short and tall primiparous women with GDM are at risk for delivering larger offspring compared to women without GDM of similar height.