I suspect it has to do with the peak suction and cycling speed of the pump, as well as the suction needed by the individual mother in order to overcome the resistence of the muscles of the nipple-areolar complex. Pumps work by pulling milk out of the breast by subjecting the nipple to a vacuum, which increases the pressure differential between inside the breast and outside. When the pressure is reached that overcomes the resistence of the muscles, they let go and the milk sprays or drips out. For some mothers, the personal double electric breastpumps are enough to overcome their muscle resistence, and fast enough for her to get milk in a reasonable time. For other moms, the resistence is higher, and they need a higher peak negative pressure (suction) than the small pumps can provide. I have had quite a few mothers in my practice who had much better response to the hospital grade pumps, and others who did fine on the smaller ones. I even have one mother who relactated at 3 weeks postpartum with a small handheld electric pump! My own personal "acid test" of whether a personal pump will work for an individual mother is whether they can pump sucessfully (get sustained multiple sprays of milk, and 3+ MERs per pumping) with the hospital grade pump on minimum or less than half way to maximum. Unfortunately, women who have just spent in the neighborhood of $300 on a personal pump are often unwilling to rent a hospital grade pump, and I have seen too many of them suffer dwindling milk supplies. Sigh. -- Catherine Watson Genna, IBCLC New York City mailto:[log in to unmask] *********************************************** To temporarily stop your subscription: set lactnet nomail To start it again: set lactnet mail (or digest) To unsubscribe: unsubscribe lactnet All commands go to [log in to unmask] The LACTNET mailing list is powered by L-Soft's renowned LISTSERV(R) list management software together with L-Soft's LSMTP(TM) mailer for lightning fast mail delivery. For more information, go to: http://www.lsoft.com/LISTSERV-powered.html