The Effect of Maternal Age and Parity on Birth Weight Among Bengalees of Kolkata, India Samiran Bisai, Amitava Sen, Dilip Mahalanabis, Nandini Datta and Kaushik Bose CHAPTER 19 INTRODUCTION Low Birth Weight (LBW), birth weight less than 2500 gm (WHO, 1984) and perinatal mortality are important public health problems in developing countries (Tafari, 1981; Edouard, 1985) particularly in the Indian subcontinent, where the LBW rates are 30-50%, which are among the highest in the world (UNICEF-ICMR, 1987). The national neonatal perinatal database reported that nearly about one third of all neonates born in major hospitals of India every year are LBW. Of all the neonatal deaths, nearly 82% occur among LBW (NNF, 1995), which is the highest in the world. The LBW is a consequence of either preterm (<37 weeks of gestation) delivery or intrauterine growth retardation (IUGR) or of both (WHO, 1984). In addition to short-term consequences, such as high infant mortality and childhood growth failure among survivors (Pojda and Kelley, 2000), growth retar- dation is a major public health problem worldwide. Foetuses who suffer from growth retardation have higher perinatal morbidity and mortality (Williams et al., 1982; Villar et al., 1990; Balcazar and Haas, 1991), and are at an increased risk of sudden infant death syndrome (Oyen, 1995). During childhood they are more likely to have poor cognitive development (Low et al., 1992; Paz et al., 1995) and neurological impairment (Parkinson et al., 1981; Villar et al., 1984; Taylor et al., 1989). The causes of LBW are multifactorial (Kamala- doss et al., 1992): it is associated with sex of baby (Oni, 1986; Kramar, 1987; Pakrasi et al., 1985), maternal hemoglobin level during pregnancy, hard manual labour (Ghosh et al., 1977), maternal nutrition (Fredrick and Adelstein, 1978), economic condition (Pakrasi, 1985; Dhall and Bagga 1995), maternal height, antenatal care (Kamaladoss et al., 1992, Rehan, 1982), parents education (Mukhija and Murthy, 1990), maternal weight (Mavalankar et al., 1994), tobacco consumption (Verma, 1983), place of residence (Mukhija and Murthy 1989), season of the year, ethnicity (Bantji, 1983), and most importantly mother’s age and parity (Cramer, 1995). MATERIALS AND METHODS The cross-sectional retrospective study was conducted from April 26, 2002 to August 14, 2002. A total of 331 Bengalee mother-baby pairs were examined in the obstetric ward of M.R. Bangur Hospital. This hospital is located in South Kolkata that serves the needs of individuals belonging to the lower class socio-economic group. Written consents were obtained from all those who participated in the study. Data were collected from hospital records followed by personal interview of mothers for confirmation of age (completed years), ethnicity and reproductive history. Three criteria were used for the inclusion of subjects: (a) the mother tongue of women was Bengali language (b) singleton live born baby by normal vaginal delivery and (c) baby did not suffer from any congenital malformation or any sickness during the time of examination. Gestational age was assessed by Ballard’s (Ballard et al., 1977) physical and neurological maturity scoring method within 24 hours of birth then matched with gestational age as calculated from maternal last menstrual period (LMP). In case of unavailability of LMP, the gestational ages were considered using Ballard’s score for classifi- cation of maturity (preterm, term, post term) and weight-for-gestational age {small for date (SFD), appropriate for date (AFD) and large for date (LFD)}. Birth weight was measured by triple beam balance without clothing under radiant warmer to the nearest 1gm. The scale was calibrated daily using standard weight and checks to ensure zero error before weighing each baby. Data entry and statistical analyses was done using the EPI-INFO (Dean et al., 1995) package. ANOVA was used to study difference between groups for continuous variables. Odds ratio was calculated to measure the risk between the groups. Chi-square test was used to study the significance of difference between proportions of categorical outcomes. RESULTS Of the 331 singletons live born babies, 178 (53.8%) were boys and 153 (46.2%) were girls. The