Intrauterine growth standards in a developing country: a study of singleton livebirths at 28-42 weeks' gestation.

This study aimed to develop fetal growth charts for the population of Greater Beirut, Lebanon, and compare them with previously established references. A survey of consecutive singleton livebirths admitted to normal nurseries and neonatal intensive care units of major hospitals, through the database project of the National Collaborative Perinatal Neonatal Network was used as a design. The study was conducted in nine major healthcare institutions serving the population of Beirut and its suburbs. A total of 24 767 singleton livebirths delivered between 28 and 42 weeks' gestation, with known data on gender, gestational age and anthropometric characteristics were recorded between 1 April 1999 and 31 March 2002. Growth charts were developed by plotting birthweight, length and head circumference percentiles against gestational age for male and female infants separately. Overall, 1348 (5.4%) pregnancies were delivered before 37 weeks' gestation and 1227 (4.9%) were low birthweight. Male infants were delivered slightly earlier than their female counterparts and the mean birthweight, length and head circumference were consistently higher in males. A total of 2247 (9.1%) infants were small-for-gestational-age, with a male-to-female sex ratio of 1.03. Using previously established growth references that overestimated small-for-gestational-age prevalence resulted in a greater proportion of false positives. The opposite was true for growth references that underestimated small-for-gestational-age prevalence. The current growth charts present useful tools for assessing the general health status of newborn infants delivered at sea level in the urban areas of Lebanon and other East Mediterranean countries.