In early pregnancy the areola around the nipples darkens and the diameter increases.

The Montgomery's glands enlarge and tend to protrude.

The surface blood vessels of the breast may become visible due to increased circulation, and this may give a bluish tint to the breasts.

By the 16th week, the breasts begin to produce colostrum:

• It is a yellowish secretion from the nipples, which thickens as pregnancy progresses
• It is extremely high in protein 
• It contains antibodies that help protect the newborn baby from infection 
• Near the end of pregnancy, the nipples may produce enough colostrum to make wet patches on the woman's clothes. Reassure her that this is normal and a good sign.
• After the baby is born, colostrum is produced for about the first three days, before the proper milk begins to flow. Make sure that the mother breastfeeds the colostrum to her baby, so she gets all the nutrients and antibodies it contains.