Input (grade 13): As weight is easier to determine than gestational age, the World Health Organization tracks rates of low birth weight (WHO | Data and statistics It is estimated that one-third of these low birth weight deliveries are due to preterm delivery.
Output (grade 10): For this reason, the World Health Organization tracks rates of low birth weight instead. WHO | Data and statistics It is estimated that one-third of these low birth weight deliveries are due to premature delivery.