Rates and risk factors for preterm birth and low birthweight
Research snapshot 1
Preterm birth2 continues to be a major public health problem contributing to 75% of neonatal mortality worldwide. Low birth weight (LBW)3 is an important but imperfect surrogate for prematurity when the accurate assessment of gestational age is not possible. While there is an overlap between preterm birth and LBW newborns, those that are both premature and LBW are at the highest risk of adverse neonatal outcomes. Understanding the epidemiology of preterm birth and LBW is important for the prevention and improved care of at risk newborns.
The authors conducted data analyses using the Global Network’s population-based registry of pregnant women and their babies in rural communities in six low- and middle-income countries (Democratic Republic of the Congo, Kenya, Zambia, Guatemala, India (two sites) and Pakistan). Trained study staff enrolled all pregnant women in the study catchment area as early as possible during pregnancy and conducted follow-up visits shortly after delivery and at 42 days after delivery. The authors analysed the rates of preterm births, LBW and a combination of preterm birth and LBW from January 2014 to December 2018 and LBW and the risk factors associated with these outcomes.
A total of 272,192 live births were included in the analysis. The overall preterm birth rate was 12.6% (ranging from 8.6% in India/Belagavi site to 21.8% in Pakistan), the overall LBW rate was 13.6% (ranging from 2.7% in Kenya to 21.4% in Pakistan) and the overall rate of both preterm birth and LBW was 5.5% (ranging from 1.2% in Kenya to 11.0% in Pakistan). Risk factors associated with preterm birth, LBW and the combination were similar across sites and included nulliparity [RR − 1.27 (95% CI 1.21–1.33)], maternal age under 20 years [RR 1.41 (95% CI 1.32–1.49)], severe antenatal haemorrhage [RR 5.18 95% CI 4.44–6.04)], hypertensive disorders [RR 2.74 (95% CI − 1.21–1.33] and one to three antenatal visits versus four or more [RR 1.68 (95% CI 1.55–1.83)].
The results show that younger, nulliparous women with limited access to antenatal care services are at higher risk of preterm births and need more attention to prevent prematurity and LBW.
1 Pusdekar, Y V, Patel, A B, Kurhe, K G, Bhargav, S R, Thorsten, V, Garces, A and al (2020) Rates and risk factors for preterm birth and low birthweight in the global network sites in six low- and low middle-income countries. Reproductive health, 17(Suppl 3), 187. https://doi.org/10.1186/s12978-020-01029-z
2 Birth before 37 weeks of pregnancy
3 Birth weight below 2500g