The recent Consumer Electronics Show in Las Vegas unveiled a whole host of products for pregnant women and infants. Among them, the promise of new breast pumps that quietly and discretely fit into a woman’s bra to pump uninterrupted as they go about their day.

For breastfeeding mothers, pumps can become an essential part of their routine. Mothers looking to provide milk for their babies are especially reliant on a good electronic pump for their workplace. But how do you pick the right one?

If you know that you’ll be pumping, start thinking about your pump early. Many are covered by insurance and can be obtained while you are pregnant. There are technical considerations—do you want a closed system pump? That means that there is a barrier between the milk and the mechanics of the pump. Open system pumps can never be fully cleaned, so it may be advantageous to have a closed system where there are less concerns about milk contamination and mold. Also, check the pumps warranty as it might give you an idea of the pump’s reliability.

Aside from product specifications, there are practical tips for picking a pump that you may use frequently in public or at work. The options for convenience are rising as the technology for pumps grows.

Do you want a pump that’s portable?

Surprisingly, many aren’t! A lot of pumps require an outlet for power, limiting your ability to travel with them. See if your pump can run on a rechargeable battery before buying it. If you are a pumping woman on the go, also consider a light weight pump. Some pumps that fit in your bra weigh less than a pound, others can be as heavy as seven pounds and need to be carried in their own bag. This doesn’t include the milk you will pump and any paraphernalia you need for pumping. So be thoughtful about the amount of space the pump takes up.

Additionally, finding a pump with fewer parts means less to clean and less to lose. When you choose popular pump brands it affords you the ability to replace parts easily. This can be helpful when you are pumping on vacation and stressing about a broken part impeding your pumping.

How efficient and fast is the pump at removing milk?

Some pumps are more powerful than others. You will want to set the suction on your pump to the lowest vacuum level that will help let down milk. Sometimes though that suction needs to be high, and some pumps might not have that ability. There are also pumps that focus on more than just suction power and will vary how fast or slow they move the nipple in and out of the flange or plastic nipple cover. This can help mimic the suck of an infant and some find it useful to have that variation in movement. Again if you crave efficiency, focusing on fewer parts to disassemble and wash may be the way to go.

Is the pump discrete?

Some pumps are LOUD. You might think that you can take a phone call while you are pumping away, but the sound of the motor will give you away. Newer pumps now have prioritized quiet. Additionally, pumps that are hands free and can fit under your shirt or in your bra, which offers pumping mothers the ability to pump unnoticed. It can also mean that women don’t have to take their breasts out of their shirts to place them on the pump. For some, not having to show skin might make pumping more comfortable in public or around co-workers.

The last thing to remember about pumping is to advocate for yourself. Even if your pump is loud and heavy with parts a plenty, getting milk for your baby is never something to feel ashamed about. Often when you let others know that pumping is a priority, they will help to accommodate you. So be open and free about providing for your baby!

Joanna Parga-Belinkie, M.D., is a neonatologist at Children’s Hospital of Philadelphia, and a medical podcaster and co-creator of Baby Doctor Mamas.