Low birthweight infants in twin gestation

Abstract

Twin gestations are commonly associated with delivery of low birth weight infants. Despite the fact that Nigeria has the highest incidence of twinning in the world, there is paucity of information on the characteristics of LBW twin infants in Nigeria. This study was con-ducted to determine the incidence and document some of the characteristics of low birth weight (LBW) twin infants. A descriptive analysis of data on 119 LBW twin infants deliv-ered between 1st January, 2000 and 31st December, 2003 in a Nigerian mission hospital in Benin City was carried out. The characteristics of the LBW twin infants was studied in rela-tion to perinatal mortality. The overall prevalence rate of LBW twin infants was 51.7% with a female preponderance. Of the 107 live-born LBW twins, 74 (69.2%) were preterm and 33 (30.8%) term small-for-gestational age (SGA) infants respectively (p<0.001). Twen-ty six (35.1%) of the 74 preterms were very preterm (<32 weeks gestation), corresponding to 24.3% of all LBW twin infants. The associated perinatal mortality for the two categories of LBW infants were 21.6% for preterm and 9.1% for term SGA infants (p>0.05). Of the 119 LBW twin infants, 7.6% were extremely LBW, 10.1% very LBW while 57.1% were low birth weight. Fifty one (42.9%) of LBW twin infants weighed less than 2000g. The risk of delivery of LBW twin infants was significantly higher in primiparous women (p<0.001), as well as in mothers who were unbooked (p<0.001) or lacked formal education (p<0.01). Out of 107 live-born LBW twin pairs, 19 (17.8%) had birthweight difference = or > 20%, with 6 of the 19 (31.6%) exhibiting birthweight difference = or > 30%. In twin gestations, preterm delivery is a more important contributor to LBW than term SGA delivery with majority of these preterm infants delivered to primiparous mothers.