Objective: To compare the time of colostrum expression and quantity of breast milk between early postpartum women who practiced exclusively breastfeeding and who had combined breast and bottle feeding.
Material and Method: Seventy mothers who delivered term normal, singleton infants were voluntarily recruited during immediate postpartum period and allocated into two groups. Study group was 35 mothers who practiced exclusively breastfeeding and 35 mothers who practiced combined breast and bottle feeding were control group. Expression of colostrum at 12, 24, and 48 hours and quantity of breast milk at 48 hours after delivery were evaluated and compared between two groups.
Results: At 12 and 24 hours after delivery, 65.7% and 88.6% of study group had colostrum compared to 37.1% and 68.6% in control group, respectively. The difference was significantly higher in study group. However, at 48 hours after delivery, there was no statistical difference in both groups. Quantity of breast milk at 48 hours after delivery was 5 mL (2, 10) in the study group compared to 2 mL (0,8) in the control group, which was significantly different.
Conclusion: Exclusively breastfeeding since immediate postpartum significantly promote earlier expression of colostrum and higher quantity of breast milk.

Keywords: Breastfeeding, Bottle feeding, Colostrum