Prevalence of low birth weight and its associated factors: Hospital based cross sectional study in Nepal

**Background:** Low birth weight (LBW), defined as birth weight <2500 g, is a major public health problem globally and a key contributor to neonatal mortality, especially in developing countries like Nepal. LBW is associated with increased risks of cognitive deficits, motor delays, cerebral palsy, and later-life cardiovascular disease. The global prevalence is estimated at 15–20%, with South Asia having the highest regional estimate (28%). In Nepal, the 2016 Demographic Health Survey reported a prevalence of 12%, but hospital-based studies have shown rates ranging from 12% to 39.6%. The government has implemented programs to improve maternal and neonatal health, yet LBW remains a challenge. This study aimed to assess the prevalence and associated risk factors of LBW in two tertiary hospitals in Kathmandu, Nepal.

**Methods:** An institution-based descriptive cross-sectional study was conducted from September 2019 to August 2020 at Paropakar Maternity Hospital and Tribhuvan University Teaching Hospital in Kathmandu. A total of 308 postnatal mothers (154 from each hospital) with singleton live births were included. Exclusion criteria included serious obstetric/medical conditions, multiple pregnancies, unknown last menstrual period, antepartum hemorrhage, congenital malformations, and maternal conditions like diabetes, hypertension, cardiac disease, or chronic infections. Data were collected via face-to-face interviews using a semi-structured questionnaire, supplemented by ANC cards and maternity registers. Birth weight was measured in grams and categorized as LBW (<2500 g) or normal (≥2500 g). Independent variables included sociodemographic factors (age, ethnicity, education, occupation), maternal obstetric factors (height, weight gain, gestational age, parity, birth interval, pregnancy intention, history of abortion), behavioral factors (tobacco, alcohol), diet-related factors (dietary patterns, food taboos), health service factors (ANC visits, deworming, hemoglobin level), and compliance with iron-folic acid (IFA) supplementation (compliance defined as intake of ≥144 tablets, i.e., ≥80% of the recommended 180 tablets). Data were entered in EpiData 3.1 and analyzed using SPSS version 21. Multivariate logistic regression was used to identify factors associated with LBW, reporting adjusted odds ratios (AOR) with 95% confidence intervals (CI). A p-value <0.05 was considered significant.

**Key Results:** The mean birth weight was 2.96±0.59 kg, and 15.3% (47/308) of newborns had LBW. The mean maternal age was 25.7±4.8 years. Most mothers were aged 20–29 years (70.4%), non-Dalit (85.7%), had formal education (91.2%), were homemakers (77.6%), had height ≥145 cm (96.1%), gained ≥10 kg during pregnancy (61.7%), had gestational age ≥37 weeks (90.6%), attended ≥4 ANC visits (91.6%), and were non-anemic (87.7%). IFA compliance was 77.6% (239/308). In multivariate logistic regression, three factors were significantly associated with LBW: Dalit ethnicity (AOR = 2.9, 95% CI = 1.2–7.1, p = 0.017), fewer than four ANC visits (AOR = 2.6, 95% CI = 1.0–6.6, p = 0.045), and non-compliance with IFA supplementation (AOR = 2.1, 95% CI = 1.0–4.4, p = 0.031). No significant associations were found for maternal age, education, occupation, height, weight gain, gestational age, parity, birth interval, pregnancy intention, history of abortion, tobacco/alcohol use, food taboos, deworming, or hemoglobin level.

**Clinical Implications:** This study demonstrates that LBW remains a significant problem in Nepal, affecting approximately one in six newborns in these hospital settings. The identified risk factors—Dalit ethnicity, inadequate ANC visits, and poor IFA compliance—are modifiable through targeted public health interventions. The strong association with Dalit ethnicity underscores the need for culturally sensitive programs that address social disparities and improve healthcare access for disadvantaged groups. Ensuring that all pregnant women attend at least four ANC visits and adhere to daily IFA supplementation (≥144 tablets) could substantially reduce LBW rates. These findings support the current national strategies of counseling during ANC, routine IFA supplementation, and nutrition programs for food-insecure areas. However, the study's limitations include its hospital-based design, which may limit generalizability to community settings, and the lack of assessment of other potential risk factors such as micronutrient deficiencies and environmental exposures. Future research using case-control or cohort designs is recommended to further elucidate causal relationships and inform policy.