Alexander Waits1, Chao-Yu Guo2, Li-Yin Chien3. 1. Institute of Public Health, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan; Taoyuan General Hospital, Taoyuan City, 32748, Taiwan. 2. Institute of Public Health, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan. 3. Institute of Community Health Care, National Yang Ming Chiao Tung University, Taipei, 11221, Taiwan. Electronic address: lychien@ym.edu.tw.
Abstract
OBJECTIVE: Low birth weight (LBW) is associated with adverse health outcomes. Incidence of LBW in Taiwan grew from 5% in 1997 to 8.4% in 2016. This study aims to identify the role of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) in LBW rate changes during 2011-2016. MATERIALS AND METHODS: We analyzed 66 135 postpartum women from 6 cross-sectional national surveys. Data were collected through telephone interviews with randomly selected mothers. Logistic regression was applied to assess contribution of maternal characteristics to LBW time changes. RESULTS: LBW increased from 5.3% to 7.0% during 2011-2016 (crude odds ratio (OR) = 1.04/year, p-value for trend = 0.001). Inadequate GWG increased from 27.9% to 41.5% (p-value for trend <0.001). Along with the increase in overweight (9.7%-11.1%) and obese (4.8%-7.4%), prevalence of underweight fluctuated between 16.0% and 17.8%. LBW increased in underweight group from 6.3% to 9.5% (crude OR = 1.09/year, p-value for trend<0.001). Adjustment for GWG attenuated odds ratio per year in total sample (adjusted OR = 1.03, p-value for trend = 0.04) and in underweight (adjusted OR = 1.08, p-value for trend = 0.002). CONCLUSIONS: Increasing percentage of women with inadequate GWG could contribute to LBW increase in Taiwan during 2011-2016, especially for the underweight. Prenatal advice on GWG should be individualized according to pre-pregnancy BMI.
OBJECTIVE: Low birth weight (LBW) is associated with adverse health outcomes. Incidence of LBW in Taiwan grew from 5% in 1997 to 8.4% in 2016. This study aims to identify the role of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) in LBW rate changes during 2011-2016. MATERIALS AND METHODS: We analyzed 66 135 postpartum women from 6 cross-sectional national surveys. Data were collected through telephone interviews with randomly selected mothers. Logistic regression was applied to assess contribution of maternal characteristics to LBW time changes. RESULTS: LBW increased from 5.3% to 7.0% during 2011-2016 (crude odds ratio (OR) = 1.04/year, p-value for trend = 0.001). Inadequate GWG increased from 27.9% to 41.5% (p-value for trend <0.001). Along with the increase in overweight (9.7%-11.1%) and obese (4.8%-7.4%), prevalence of underweight fluctuated between 16.0% and 17.8%. LBW increased in underweight group from 6.3% to 9.5% (crude OR = 1.09/year, p-value for trend<0.001). Adjustment for GWG attenuated odds ratio per year in total sample (adjusted OR = 1.03, p-value for trend = 0.04) and in underweight (adjusted OR = 1.08, p-value for trend = 0.002). CONCLUSIONS: Increasing percentage of women with inadequate GWG could contribute to LBW increase in Taiwan during 2011-2016, especially for the underweight. Prenatal advice on GWG should be individualized according to pre-pregnancy BMI.