Some women are thrilled to have 40 weeks of expanding breasts, while others are happier with the breasts they had before becoming pregnant. If one thing is certain, expecting women will have to deal with breast growth, pain, and milk production as a part of the pregnancy journey. Why and how do breasts grow during pregnancy?

Weeks 4 to 6

Around the 4th to 6th week of pregnancy, breasts will start to feel a bit tender and painful to the touch. This is the effect of pregnancy hormones and often the first sign of pregnancy. Many women write off this pain as being associated with an impending menstrual cycle but soon realize pregnancy is the real cause.

Weeks 8 to Birth

Starting in the 8th week of pregnancy, hormones start changing breast tissue causing the breasts to expand. Most of the growth is associated with increased fluid retention early on. Real milk will not develop in the breast until after birth.

Weeks 12 to Birth

Around the 12th week, colostrum starts being produced. Colostrum is a rich milk that is the most important gift a woman can give her baby. Women who do not plan on breastfeeding often choose to allow baby to nurse for the first few days to pass only the antibodies and healthy nutrients present in colostrum.

Other Breast Changes

Enlarging breast tissue may be enough change for mom in this sensitive area, but those pregnancy hormones do much more than cause growth. The nipple and areola may grow larger as well. Areola changes can also include a darkening of the skin and appearance of bumps around the nipple. Itchy and irritated skin will also result from all the changes in breast tissue and milk ducts during pregnancy.

Finding the Right Bra

Breasts can grow to be one, two or three cups sizes larger during pregnancy. Women who are carrying their first baby often see more dramatic growth. During this time, the woman will need to buy a few new bras to hold in those growing breasts. The first new bras should not be nursing bras if breastfeeding. Growth does not stop until the end of pregnancy, so spending extra money on nursing bras in the second trimester will just be a waste by the time baby is born.