Reduced milk supply in one breast

Why did my milk supply decrease on one side?

Milk supply may decrease on one side for various reasons: the mother may be offering that breast less than the other, may be starting all feeds on the other side, or be expressing milk ineffectively on that side. Her baby may just prefer the other breast or may not feed effectively on the less active side. She may have one inverted nipple or had plugged ducts, mastitis, or an abscess. In these situations, the mother needs to make sure the baby is receiving enough milk. We recommend starting feeds on the breast that produces less milk. This ensures the baby stays interested in both sides. Most normal mothers have one breast that is slightly larger and more productive than the other. 

A) Describing differences in milk supply between breasts

1) Normal differences

Most mothers have one breast that is slightly larger than the other and that produces slightly more milk. This is normal. In this situation, it is best to offer each side equally.

2) Abnormal differences

Large differences in size may be caused by specific problems that were present before birth. Differences in milk supply may also develop after birth as one breast reduces the amount of milk made.

Having one breast with a low milk supply can lead to the baby not taking in enough milk. In addition, babies frequently prefer the more active breast and may become reluctant to breastfeed on the weaker side or may even reject it completely. Mothers should start all feeds on the weak side. 

B) Causes of a reduced milk supply in one breast

If one breast starts making less milk than it did earlier, the problem may be temporary or permanent. It may be caused by any the following: