What is OAL?
OverActive Letdown is a condition with a lot of names. It is also called foremilk-hindmilk imbalance, oversupply syndrome, and hyperlactation, and each of these names describes only a part of the whole picture, in my opinion. It is a common cause of reflux, and is relatively easy to rule out, which is why I recommend this as a first step before looking further. It can also be a hard idea to accept. No mother wants to consider the possibility that her nursing pattern may be causing her baby’s suffering, including me! I resisted suggestions that too much foremilk might be an issue for me and my children until I was nursing my fourth baby. Somehow, admitting that this could be a problem made me feel like I had been going about nursing in the wrong way.
Please remember that too much foremilk is not caused by nursing “incorrectly!” Every mother and every baby is different. It is impossible to say how long is too long to nurse on one side, or how soon is too soon to switch to the other side, because it is different for each of us. Some babies will be more sensitive to foremilk than others, and some mothers will produce more foremilk in a shorter time than others. Each mother and baby’s solution to this problem will be a little different than everyone else’s solution.
The really nice thing about this problem is that it’s easy to tweak your nursing patterns and watch for improvement. All you need is a little understanding of how your breasts make milk, and to examine your current nursing pattern. The composition of milk changes throughout each feeding. At the beginning of the feeding, the baby gets “foremilk,” which is thinner and has less fat than the milk that comes later during the feeding. As the baby sucks, the breasts produce milk that is thicker and has more fat. When a baby gets too much foremilk for his digestive system to handle (foremilk-hindmilk imbalance), the typical symptoms are fussiness, gassiness, spitting up or vomitting, and very frequent stools that are usually, but not always, green. When the breasts are producing too much milk (oversupply or hyperlactation), the letdown is often very strong (overactive letdown), and the baby will gag or choke, or even let go completely. Milk will sometimes spray or leak out of the side that the baby is not using. Often when a mother has this problem, the baby will nurse better while lying down (which is contrary to reflux logic), because the heavy flow is easier that way.
To figure out how to get more hindmilk, consider your usual nursing pattern. How often do you switch sides? The longer a baby nurses on one breast, the more hindmilk he will get. Sometimes nursing on one side per feeding works well, and other times a baby needs two or three feedings on one side before the switch. In the first few days after birth, babies need to switch sides frequently to build up the mother’s milk supply, but after the milk comes in, switching sides during every feeding is not always necessary. How long does your baby go between feedings? Foremilk builds up in your breasts between feedings, so the longer he waits, the more foremilk there will be. What position does your baby seem most comfortable nursing in? Are there any feedings that always seem to make him fussy? Are there any that never seem to?
You may find when that you get very full on the other side when you first start changing your nursing pattern. Expressing some milk from that side will help keep you comfortable, but remember the rule of supply and demand and don’t express so much that your breasts think you need all that extra milk!
Also remember that foremilk is not “bad” milk; your baby needs foremilk, just not quite as much as he’s been getting! Expressing all the foremilk and only giving your baby hindmilk could possibly lead to dehydration.
If your baby’s reflux is affected by oversupply/overactive letdown/foremilk-hindmilk imbalance, you should see some improvement within the first few feedings that get him less foremilk and more hindmilk. It will probably take a week or more for your milk supply to even out and get used to the changes you’ve made.
Most breastfeeding books have sections about this condition where you can learn more. (My personal favorites are "The Breast Book" by Martha and William Sears, and "The Nursing Mother’s Companion" by Kathleen Huggins.) I strongly recommend contacting your local La Leche League Leader or certified lactation consultant as well.
Foremilk imbalance links:
The Importance of Newborn Stool Counts