Is It Better to Breastfeed or Pump?

You (and others) have written extensively about formula vs. breastfeeding. But if you’re committed to feeding breast milk, are there health/developmental benefits to breastfeeding vs. exclusive pumping? Most advice books assume the former, but they don’t really give any reason for it (besides hard-to-quantify “bonding”), and we’ve found the flexibility that exclusive pumping offers to be really useful.

—Bottle-Feeding Dad

The degree to which we do not have data on this is somewhat astonishing. Several years ago, I worked on a (now-stalled; sorry, co-authors) paper on breastfeeding trends over time. Breastfeeding rates in the U.S. were very low in the early 1970s, increased rapidly through the 1980s, stagnated, and then began to increase again in the 1990s. One theory we had for this was the improvement in pumping technology — maybe women who were returning to work were able to breastfeed for longer because pumping became possible.

To evaluate this theory, we needed to find data on the use of pumps, and it more or less did not exist. Even the surveys that asked extensive information about breastfeeding duration didn’t ask about pumping. This actually makes the data difficult to interpret. If you were exclusively pumping and someone asked if you’re breastfeeding or not — with a binary answer — what do you say? I think I would say I was breastfeeding, but someone else might not. Since the questions in surveys do not distinguish, we do not know. This has gotten a little better in data over time but not much, and certainly there are no really good studies that would tell you whether any health or developmental benefits differ.

(By the way: any differences are likely to be small, since overall, the impacts of breastfeeding are small, as I have written about a lot before.)

Without data, the best we can do is theory. Is there any theoretical reason why pumping would differ from breastfeeding? As you note, there is the bonding story, but it seems difficult to argue that snuggling your infant while you give them a bottle is fundamentally different from snuggling them while you nurse them. A snuggle is a snuggle.

There is one mechanistic argument I have seen for a possible short-term health benefit of breastfeeding in infants. Infants who nurse often get milk all over their face and up their nose, because … they’re babies and still figuring it out. If there are antibodies in breast milk that get into the infant’s nose, that might have some marginal impact on preventing respiratory infections. Having said that, we have no proof of this, and it would be an extremely short-term impact, since eventually babies figure out how to eat without covering themselves with milk.

Bottom line: There is no data-based reason to think there is any difference in these activities.