If you are going to try maintaining a breastmilk supply based solely on pumping, you need a very good, double electric pump. My pump is the Medela Pump In Style® Advanced The Metro Bag™. I find the pump comfortable and like its versatility. The big plus is that the pumping unit can be removed from the bag which makes it much easier to use on airplanes. The bag comes with a variety of nice add-ons, the most useful of which are the insulated storage bag and the two small mesh parts bags (discussed later).
In terms of pump parts, I have three full sets of shields, bottles, caps, connectors, valves, and membranes. In addition, I also travel with backup membranes both in my pump bag and in my computer bag.
Generally, for days I am in the office, I pump twice. On those days, I bring two full sets of parts. When I travel, I typically bring three full sets of parts. One set is left in the hotel and two sets go with me to the office or the client site.
On trips, I will generally bring two sets of larger bottles as well (interestingly, the 8-ounce narrow-necked Dr. Brown’s bottles that we use for feeding expressed milk fit perfectly into the connectors). I use these larger bottles for the first pump of the day as I find that I am usually too full from overnight to contain all the milk in the standard 5-ounce Medela bottles.
I am a huge proponent of hands-free pumping using a pumping bra. My preference is for the Simple Wishes version. It is important to get the one that comes with the 1-inch, zip-in insert which allows you to get the right fit in the front. There is adjustable velcro in the back, but that only addresses the tightness of the bra around the chest. It doesn’t help with aligning nipples with the openings for the breastshields.
My pump came with both a power cord and a battery pack. The power cord is the preferred method for getting energy to the unit. For pumping in the car, my preference is for an inverter that plugs into the cigarette lighter. I like the ones with two plugs because I can also charge my phone at the same time and the inverter isn’t something I will have to discard when I am done pumping because it only works as an adapter for my pump. Depending on the aircraft, many planes have power outlets connected to the armrest (in first or business class) or between seats (in economy). In my experience, Boeing has them and Airbus doesn’t and, yes, I have actually picked my flights based on which equipment I am flying so that I can have an outlet on a long-haul international flight.
The power outlets on planes operated by US carriers are 110 volts. Always check if you are flying on a non-US aircraft before plugging in your pump. Generally speaking, although the pump cord may have a bulky plug, it is not able to convert power. This means that US pumps must only be plugged into 110-volt outlets. If you are traveling outside of the United States, do not use your pump plug with an adapter or even a transformer as the likelihood that you will overload and blow out your pump’s motor is very high. In these situations, you must rely on the battery pack.
When I travel internationally, I bring two battery packs. My pump battery packs use 8 AA batteries each. To conserve cost and limit the environmental impact, I use rechargeable batteries and carry an 8-at-a-time battery charger. The charger is rated to convert power from non-US outlets and so it can be used with just an adapter. I carry two global adapters, one in my pump bag and one in my computer bag. Generally, I find that I can get two to three, 20-minute pumping sessions from each battery pack.