Predictors of Milk Production in Lactating Women

The aim of this study is to determine whether breast milk intake by the newborn infant is predicted by the growth in the mother’s breast volume during pregnancy. The relationship between breast milk intake, suckling time, birth weight and maternal breast volume were measured and also other measures of fat accumulation. Volumetric breast measurements were made on primiparous and multiparous women at 3 and 8 months pregnant and at 7 days post partum using adaptations of the methods of Hytten (1954) and Milligan et al. (1975). The mother’s body mass index and the upper arm, forearm, thigh and calf circumferences were measured during pregnancy and post partum. The infant’s spontaneous milk intake was measured on days 8 and 9 post partum by weighing the infant before and after each feed over 48 hours, using a Sartorius 3865 MP portable Top Pan Balance fitted with a baby weighing pan and coupled to a Sartorius Universal Printer. Although milk intake was reliably predicted by suckling time, as shown in previous studies, there was no significant relationship between breast enlargement and milk intake, contrary to the finding of Hytten (1954). The discrepancy is probably attributable to his use of breast pumping to measure breast milk production. In the study repeated in this thesis, the infant’s natural milk intake was measured, and was found not to be related to the mother’s breast enlargement during pregnancy. Enlargement of limb girth was detected only for the thigh; that of the arm did not change