Factors affecting birth weight in Kuwait. Part II: Pregnancy characteristics and health factors.

The aim of this was to determine the mean birth weight of Kuwaiti infants, the incidence of low birth weight and the impact of maternal age, smoking, health status, parents' consanguinity and pregnancy characteristics on infants' birth weight. The study was conducted in the major maternity hospital in Kuwait where the body weight of 1995 newborn infants was recorded shortly after birth. Data describing maternal age, duration of pregnancy, sex of the infant and maternal illness during pregnancy were recorded. Mothers were interviewed to collect data on duration between present and last pregnancy, birth order of the infant, parents' consanguinity and frequency of smoking. The results show that the mean birth weight was 3.5 Kg and the incidence of low birth weight was 3.4%. The results illustrate that young mothers were more liable to have small infants while old mothers were more liable to deliver a very heavy or low birth weight infant. The weight of the newborn infant was positively correlated with duration of pregnancy, duration between present and last pregnancy and birth order. The mean birth weight of male infants (3.51 Kg) was higher than females (3.47 Kg). Parents' consanguinity and maternal smoking had a slight effect on infants' birth weight. The results show that diabetic mothers delivered large babies. On the contrary, the incidence of low birth weight was highest (7.0%) among infants of hypertensive mothers.