[The determination of the probable term of delivery].

The full-term infants born during the leap year of 1988 in the obstetric-gynecological complex in the town of Dobrich were 2434, but the infants born according to the formula of Negele within the defined term--14 days were 2038. Most women were delivered of infants before the term. Standardization of parturients before and after term is made after estimated term with addition of 5 days to the last menses as the number of deliveries is increased as well. The difference in weight and length of infants before and on term is significant in respect to the infants born on term (with few exceptions) and insignificant between the infants born on term of labour and the infants born after the term. Duration of full-term pregnancy is 280.5-280.7 days. The probable term of delivery is determined more exactly by the formula of Negele with addition of 5 days during leap years and of 6 days during the remaining years to the first day of the last menstruation of pregnant women.