Ethnicity and fetal growth in Fiji

Maternal height, and ethnicity and birth weight: A retrospective cohort study of uncomplicated term vaginal deliveries in Malaysia

BACKGROUND

Small for gestational age (SGA) and large for gestational age (LGA) are designations given to neonates based solely on birthweight, with no distinction made for maternal height. However, there is a possibility that maternal height is significantly correlated with neonatal birthweight, and if so, SGA and LGA cutoffs specific to maternal height may be a more precise and useful tool for clinicians. To explore this possibility, we analyzed the association between maternal height and ethnicity and neonate birthweight in women with low-risk, 37- to 40-week gestation, singleton pregnancies who gave birth vaginally between 2010 and 2017 (n = 354,488). For this retrospective cohort study, we used electronic obstetric records obtained from the National Obstetrics Registry in Malaysia.

METHODS

National Obstetric Registry (NOR) data were used to calculate the 10th and 90th birthweight percentiles for each maternal height group by gestational age and neonatal sex. Multiple linear regression models, adjusted for maternal age, weight, parity, gestational age, and neonatal sex, were used to examine the association between neonate birthweight and maternal ethnicity and height. The following main outcome measures were assessed: small for gestational age (<10th percentile), large for gestational age (>90th percentile), and birthweight.

RESULTS

The median height was 155 cm (IQR, 152-159), with mothers of Chinese descent being the tallest (median (IQR): 158 cm (154-162)) and mothers of Orang Asli (Indigenous) descent the shortest (median (IQR): 151 cm (147-155)). The median birthweight was 3000 g (IQR, 2740-3250), with mothers of Malay and Chinese ethnicity and Others having, on average, the heaviest babies, followed by other Bumiputeras (indigenous) mothers, mothers of Indian ethnicity, and lastly, mothers of Orang Asli ethnicity. For infants, maternal age, height, weight, parity, male sex, and gestational age were positively associated with birthweight. Maternal height had a positive association with neonate birthweight (B = 7.08, 95% CI: 6.85-7.31). For ethnicity, compared with neonates of Malay ethnicity, neonates of Chinese, Indian, Orang Asli, and other Bumiputera ethnicities had lower birthweights.

CONCLUSION

Birthweight increases with maternal height among Malaysians of all ethnicities. SGA and LGA cutoffs specific to maternal height may be useful to guide pregnancy management.

The Asian enigma: predisposition for low adult BMI among people of South Asian descent

OBJECTIVE

To investigate the Asian enigma, the phenomenon of relatively high levels of undernutrition among children and adult women in South Asia, despite more favourable records with respect to infant mortality, women's education, food availability or other aspects of living conditions in comparison with, for example, sub-Saharan Africa.

DESIGN

Literature has been explored to identify countries outside South Asia that are home to sizeable population segments from different ethnic backgrounds, including people of South Asian and African descent, and to compare prevalence rates of undernutrition in combination with indicators of standard of living between these various population segments.

RESULTS

Data on adult undernutrition prevalence rates among population groups of different ethnic descent living in the same country (South Africa, Fiji and the USA) generally reveal the highest prevalence rates of low BMI among adults, males and females, from South Asian background. The relatively high rates of low BMI among adults from South Asian background cannot be explained by less favourable socio-economic characteristics, such as lower income or less access to food.

CONCLUSION

It is hypothesized that there exists among adults of South Asian descent an ethnic predisposition for a low BMI. Other factors that may contribute to high levels of undernutrition in South Asia are discrimination of women and a poor dietary quality of poor households' food composition pattern. The question needs to be addressed whether the commonly used cut-off point for adult underweight (BMI < 18.5 kg/m2) is universally applicable or whether ethnic differences should be taken into account.