Relative risks of low birthweight in Scotland 1980-2.

Routinely collected data for 187,000 Scottish singleton livebirths in 1980-2 were used to relate the risk of birthweight below 2500 g, 2000 g, 1500 g, and 1000 g to sex of infant and nine maternal factors. Maternal height was a major predictor of birthweight below 2500g but was less important in predicting birthweight in the lower intervals. A history of prenatal death and spontaneous abortion was important for all four intervals and was associated with most extreme risks for birthweight below 1000 g. The analysis confirms that the patterns of risk of birthweight below 2500g and 2000 g associated with social class, marital status, and maternal age and height found among the women of the 1958 cohort of British births are still applicable in the early 1980s.