Maternal Weight Gain and the Occurrence of Low Birth Weight

Abstract

Maternal Weight Gain and the Occurrence of Low Birth Weight

Wisit             Chaveepojorn DVM, MPH

Natchaporn    Pichainarong  DrPH

Department of Epidemiology, Faculty of Public Health, Mahidol University

Objective: To study the relation between maternal weight gain during pregnancy and the occurrence of infant low birth weight.

Study design: Prospective cohort study.

Subjects: Two thousand and three hundred pregnant women who attended prenatal services and delivered at 4 Maternal and Child Hospitals and Rajvithi Hospital during 9 months between 1^st July 1995 and  31^st March 1996.

Methods: Data were collected by questionnaires, record forms and medical instruments which comprised 3 parts: part 1 general characteristics including demography and socio-economy, part 2 specific information including gestational age, history of illness during pregnancy, and part 3 measurement data including body weight, height, blood pressure etc.  The obtained data were analyzed by statistical program.

Main outcome measures: Mean and standard deviation of body mass index before pregnancy and delivery, weigh gain during gestational age and infant birth weight.

Results: Group of weight gain during pregnancy < 12 kg had the proportion of LBW higher than groups of 12-16 kg and > 16 kg (p = 0.012, p = 0.025).  The average of weight gain in LBW group was less than the other one (p < 0.001).  Group of BMA at delivery < 25 kg/m² had the proportion of LBW higher than group of BMI ≥ 25 kg/m² (p = 0.001). Group of being pregnancy-induced hypertension and group of pre-term birth had the proportion of LBW higher than group of none (p < 0.001, p = 0.001).

Conclusion: Pregnant women of weight gain < 12 kg and BMA at delivery < 25 kg/m² had chance more likely to develop LBW than other groups.  Therefore, appropriate control of body weight during pregnancy was the essential measure to decrease the occurrence of LBW

Key word: maternal weight gain, low birth weight

Vajira Med J 2003 ; 47 : 123 - 131