Maternal Risks Factors and Delivery Outcome of Fetal Macrosomia in Zaria, Northern Nigeria

Although macrosomia may be associated with adverse maternal and perinatal outcome there is paucity of recent data regarding fetal macrosomia in our setting. This study was undertaken to document the prevalence and risk factors associated with fetal macrosomia and also to determine the maternal and perinatal outcome associated with the condition in Ahmadu Bello University Teaching Hospital Zaria, Nigeria. The study was a cross sectional comparative study that was carried out over a five year period (Jan 2001-Dec 2005). Case records of 207 mothersof macrosomic infants (cases) and records of 220 mothers of normal birth weight infants (control) were reviewed. Fetal characteristics such as sex, birth weight, and perinatal complications were also analyzed and comparedbetween the two groups. The prevalence of fetal macrosomia from the study was 4.2%. There was strong association between diabetes mellitus, previous history of macrosomia, gestational age of > 40 weeks, male infant sex and a body mass index at booking of > 30 with fetal macrosomia. Maternal parity was found not to be significantly associated with fetal macrosomia. Labour was significantly prolonged, and there was associated prolonged hospital stay, primary postpartum haemorrhage and genital tract laceration in women with fetal macrosomia. The incidenceof caesarean section was three times more in mothers with macrosomic infants compared to mothers with normal weighed infants. There was no maternal mortality recorded. The mean Apgar score at 1 and 5 minutes was not statistically different in the two groups. The stillbirth rate in the macrosomic infants was 4.8% compared with 2.3% among normal weighed babies. It can be concluded that macrosomia is a relatively common complication of pregnancy in our setting and is associated with maternal factors such as obesity, diabetes, previous macrosomia, prolonged pregnancy and adverse perinatal outcome. Identifying the risk factors to fetal macrosomia during antenatal period will be useful to plan appropriate delivery management to optimise good perinatal and maternal outcome