A new mom reviews two smart breast pumps

Can wearable models from Willow or Elvie rival a traditional system?

Amber Bouman / Engadget

What’s it like having newborn twins? Well, the other day while eating a cinnamon roll for breakfast at 1:30PM, I accidentally bit off the end of the plastic fork I was using and I just kept chewing because I simply did not have time to react. I am writing this from the front seat of my car, waiting to be called into my daughter's ophthalmologist appointment. It just occurred to me that I have had to pee all morning. Hopefully those charming anecdotes help colorfully illustrate for you how little time I have to sit down near an outlet and not move for at least 30 minutes while I use an electric breast pump. Frankly, I volunteered to test wireless breast pumps because, and this is not hyperbole, it is a genius idea.

There are a few wireless smart pumps on the market but two of the better-known brands are Best of CES winner Willow and UK-based Elvie. I’ve spent the past several weeks using both, plus a standard wired Spectra pump, to see how they work in real life. Is it easier to keep to a pumping schedule? Could I get more done untethered from a wall outlet? Read on for the details but be warned that I’m going to use the word ‘nipple’ a lot here.


Willow 3.0 breast pump
Amber Bouman / Engadget

Inside the box, the Willow system contains two white-and mint-green egg-shaped pumps, weighing 12.5 ounces (0.78 pound). Willow includes 24 of it’s proprietary ‘O’ shaped milk bags which fit into the flanges and over the Flextubes. The flanges then attach to the pump courtesy of several tiny magnets along the rim. The front of the pump has buttons to control pumping sessions.

The Willow offers two collection options: a flange that works with disposable bags that need to be attached before each session, and reusable flanges that can be emptied and cleaned. Each has its pros and cons. The standard flange that comes with the Willow requires proprietary bags available at Willow’s website, Amazon and Buy Buy Baby. This setup is said to be ‘spill-proof,’ according to the website, even in the downward dog yoga pose. I tested that very claim and found it to be accurate.

The other option, the reusable flanges, are sold separately. Although they’re washable, they are not spill-proof, and require the user to remember to toggle between two settings to complete a session.

Either way, when you’re done pumping you can use the ‘flip to finish’ feature to gather the remainder of the milk into the receptacle of your choice (bag or flange). You’ll then separate the pump from the breast and spin it toward you and upside down -- which seems like a surefire way to dump milk into your lap. However, the Willow system then kicks in and draws the rest of the milk into the bag or flange. It’s pretty neat to watch, but a bit of fluid always remains in the Flextube so I still needed a towel to finish or I’d wind up with a few drops of milk escaping.

Elvie breast pump
Amber Bouman / Engadget

The Elvie is also shaped like an egg, weighing a lighter 7.9 ounces (0.49 pound). The breast shields containing the flanges are a separate attachment from the collection containers. Those are clear plastic with volume markers, attaching at the bottom of the pump. The containers are designed to be set on a counter or table as you prep, which I found pretty useful. The breast shields snap in or out with an easy press or pull. On the front of the Elvie pumps are buttons for power, play, intensity  and associated side. (The Elvie pumps are not assigned automatically, whereas the Willows are marked as right and left.) There’s also a button for detaching the bottles. The pump also comes with adjusters to help the device fit comfortably inside a bra.

There is no option to use disposable bags with the Elvie, and it doesn’t claim to be spill-proof. It does claim to be silent, which it nearly is. Elvie is the quietest of all three pumps I used. It has a somewhat smaller profile, but the white indicator lights on the front of the pump glow through the user’s shirt (leading me to think of them as Iron Man Boobs).

Comfort and fit

Willow 3.0
Amber Bouman / Engadget

Following the instructions in the Willow manual, I fit the clear flange over my breast and then attached the pump to start a session. This ensures a better fit, which in turn leads to more successful pumping. If a Willow pump isn’t set correctly onto the breast, it will pause and flash an orange light. An error message on the app will tell you what the issue is so you can fix the problem. Once pumping begins, simply pull up the cup of your bra and go about your day.

Starting a session was easy enough. There were only a few times where I put things together incorrectly; even then, addressing the issues was straightforward. The Willow stayed in place nicely, and the pumping itself wasn’t uncomfortable. Just a tug and some pressure, and the process didn’t pull or pinch my nipples though I could distinctly feel it working.

Willow Reveals Third Generation Breast Pump Designed With New Tech Inside to Help Moms Pump their Most Milk Yet

However, I looked ridiculous. In contrast to the chic images of women on the Willow site using the pump while doing yoga, I looked like Jessica Rabbit in a Terry Gilliam movie; my proportions were comically exaggerated and my chest made rhythmic pumping noises. My partner would laugh at me every time he saw me using them, and I would not venture farther than the mailbox while pumping.

The Elvie pumps are thankfully smaller and much quieter. That said, I still probably wouldn’t go out in public using them. But I felt a lot better about taking conference calls. Like the Willow, the Elvie pumps are placed against the breast and secured in place by the bra; Elvie adds an adjuster in the kit to help expand straps where needed (although I personally never did).

The Elvie pumps also have much smaller flange pieces, with black indicator lines to help align the nipple correctly so you can put on the already assembled pump. Because the collection containers are on the bottom, the pump itself has a smaller profile. Elvie warns that the pumps have a tendency to get warm, but it wasn’t something I noticed until I unlatched them.

Elvie pump

Both systems offer seven intensity settings in contrast to the five on my Spectra wired pump. Because the idea is to use the highest setting that you find comfortable, I usually ran the pumps at setting 4 or 5, with good results. Both pumps automatically shift the pumping rhythm from stimulation (which signals to the breast to “let down” milk) to expression (where milk production is consistent). On the Spectra, this has to be done manually.

However, both pumps made it hard to hold my kids -- not because of the noise, which didn’t bother either of my babies in the slightest, but because of the awkward bulges in the front of my shirt. I immediately felt like Marge Simpson in the episode where she gets giant implants and can’t hold Maggie over them. Also, I was a little concerned about my kids bumping their tiny soft heads against the hard pumps.

Ease of use

Elvie breast pump
Amber Bouman / Engadget

Having several weeks of experience with wired pumps, it wasn’t too difficult to adapt to a wireless version, though there were differences. With the Willow, it was learning to install the milk bags and flanges correctly; there were a few times where I had to take the entire assembly apart and redo it to successfully start a session. While the app lets you know what the issue is, it didn’t help when one of the pumps wouldn’t connect via Bluetooth (more on that below). There were a few occasions where there was no issue reported in the app, but no milk was produced on one side. Was it due to incorrect nipple alignment? Did I seat the bag poorly in the flange?

At one point, a Flextube stopped connecting correctly to one of the reusable flanges and, despite retrying it several times, I never could get that particular flange to work again (though the Flextubes worked fine with the standard flanges and the other reusable flange). If I hadn’t had other options to complete my session, I would have been a lot more upset. Twice I forgot to toggle the switches on the reusable flange before finishing a session using Willow’s ‘flip to finish’ feature, which meant I spilled milk in the process. But that’s on me.

With Elvie, the main issue was seating my nipple inside the breast shield. Despite the markings on the shield, there were still a few sessions where I apparently hadn’t lined up well enough, resulting in hardly any milk, sometimes from one side sometimes from both. This happened at least three times, and there wasn’t a lot of information to help me figure it out.

Breast pump app screenshots
Willow / Amber Bouman / Engadget

Despite these being smart breast pumps, the paired apps were the least impressive part. The pumps work just fine without pairing, and I ran into issues with both the Evie and Willow apps. However, one of the Willow pumps (the right one) almost never connected to the app. I tried to follow the troubleshooting instructions, to no avail. In fact, only two or three of my sessions had both pumps connected, meaning I was only getting half the metrics on battery life and volume.

This was frustrating, and also made the app seem superfluous. I contacted Willow about this, and asked if resetting the pump would fix the issue; they recommended that I try out the reset.  While this did appear to solve the problem -- even populating the app with my metric history -- the pump still wasn’t connected during my next session. Also, the reset wasn’t something that was necessarily easy to troubleshoot using the manual which simply advises resetting the device “when device needs to be reset.”

Elvie app
Elvie / Amber Bouman / Engadget

Elvie had its own snags. Because I tried out the pumps before I paired them to the app, the first time I opened the program it showed a pumping history from 1970. There were also at least two sessions where the app showed that I had produced much more milk than the bottles had in them. Not dealbreakers, but again, not things that made the app portion of the product feel essential.

There were some useful features, like controls built into the Evie app allowing you to pause, start or finish a session from your phone. Likewise, the Willow app displayed the time left in a session and pumping history was practical. The best parts of the apps were watching the volume of milk collecting and having a record of session metrics and information.

Battery life

Elvie breast pump
Amber Bouman / Engadget

The appeal of a smart breast pump system -- the ability to put the whole pump in your bra for complete freedom of movement -- comes with some predictable trade-offs. Much like a set of Bluetooth earbuds, you have to be mindful of keeping the pumps charged so they’re ready to go when you are. As someone who lives on an off-grid property that relies on solar energy, I’m always looking for a battery-powered solution that allows me to charge during the day so I can avoid pulling power at night.

For obvious safety reasons, neither pump will allow you to use it while it’s charging. Willow pumps charge via a 120V charging cable with a port on the underside of the pump. There’s one charging cable included in the kit; you can also purchase extras separately for $30. Elvie uses a more universal micro-USB charger, located in a covered port on the side of the pump.

The Willow pumps take two hours to fully charge but can store enough power for a single session in 25 minutes. Elvie offers the same two-hour charging time. Willow claims that the battery should last for five sessions lasting 25 minutes apiece. In practice, however, I found that the right pump consistently lost battery faster than the left. Sometimes I’d start with a fully charged battery and get a low-power warning halfway through a session. More than once, I’d go to start only to find the right pump flashing red and in need of a charge, while the left one was green and ready to go. Willow said that it could be because the pump is attempting to download a firmware update but had been turned off before it could be completed. I followed their instructions, which fixed the issue for a day or so before it occurred again.

Elvie says the batteries on its pumps should last about two-and-a-half hours at standard settings. In my testing, they seemed to run longer than the Willow ones; I generally managed to get around three sessions over 48 hours out of the Elvie pumps, while I had to charge that errant right Willow pump often. The left one seemed to last much longer, keeping its charge for one or two sessions daily over about three days. I’m hoping that trying the firmware fix again will produce better results for the Willow pump going forward.

Cleaning and sterilizing

Willow 3.0
Amber Bouman / Engadget

As with any breast pump, all the parts that touch the breast or funnel breast milk through the system must be initially sterilized by boiling in water for five to 10 minutes (some allow for microwave or machine sterilization). Then the components need to be washed and air-dried after each use. The pumps themselves only need to be wiped with a clean dry cloth.

Willow claims its system is easy to clean because there are only two parts: the flange and the Flextube. However, these two parts include a few small tubes and tunnels that have to be cleaned with the included brushes. And the Flextubes take a rather long time to air dry. I found myself wishing I had an extra set so that I wasn’t forced to wait for them to dry before I started another session.

Elvie’s system has more parts to clean: five on each side, including the bottles, spouts, valves, seals and breast shields. However, there are no tiny tunnels to brush clean, making it a bit easier. Everything except for the bottles dried quickly.


Elvie breast pump
Amber Bouman / Engadget

There’s no getting around the price for either of these systems. Willow’s most recent model, the Gen 3, costs $500. Elvie has two options: a single pump for $279 or a dual pump setup, which includes two of every kit piece for $499. Both sets can be purchased with FSA/HSA funds, at least.

In a world where a flagship smartphone will set you back over a grand and earbuds can run up to $350, this may seem fair for a niche product. But my Spectra S2 retails for $159, and the more fully featured Medela Sonata costs $359. You’re paying for the convenience of disconnecting from a wall plug. It’s largely worth it, especially if you can get or use an insurance refund.

Elvie offers a two-year warranty on the pump, and a 90-day warranty on any of the washable parts. The expected lifespan of the Elvie washable parts (breast shield and bottle) is six months; a three-pack of replacement bottles runs $35 on Elvie’s site and the breast shields cost $30 for a two-pack.

Willow, meanwhile, provides a year on the pump and 90 days on the other components. The flange and Flextube for the Willow system should be replaced every three months; a two-pack of flanges is $30 and the Flextubes run $30 for a two-pack.


Elvie in bra

Willow has made a name for itself for a reason: It has an innovative product with multiple features and a dedicated fanbase. Even though my set didn’t always work exactly as it was supposed to, I still appreciated the ability to brush my teeth, clean baby bottles and walk from room to room while pumping. Admittedly, I wish the Bluetooth connection was more consistent. The battery issues were disappointing too. Overall, I still found myself waiting for the Willow pumps to charge instead of opting for my wired Spectra, which says something about how useful the product is.

Elvie’s pumps offer a similar freedom with different features. I appreciated the ability to view the bottles to make sure the pumps were collecting, as well as the nearly silent pumping noise and slimmer profile. If I had to choose just one, I’d opt for the Elvie largely thanks to the Willow’s finicky Bluetooth and battery. But if another mom asked me if it was worth the investment to buy either pump system, I would still recommend either over a wired pump.

Update: Elvie reached out to us to let us know that after our review was published, the company issued a firmware update that enabled the option to dim the lights on the pumps, so that they no longer shine through fabrics. Additionally, in the original version of this review we referred to the doctor mentioned in the first paragraph as an optometrist; the correct term is ophthalmologist. We regret the error.

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