Mom with Hyperlactation Breaks Record for Breast Milk Donated. But She'll Need Double Mastectomy to Stop (Exclusive)

Elisabeth Anderson-Sierra, a mom of three, tells PEOPLE about spending hours pumping daily and finding a silver lining to a syndrome that disrupted her life

Elisabeth Anderson-Sierra's body doesn't function like most.

Since welcoming her first baby eight years ago, the now-mom of three learned that she's living with hyperlactation syndrome, a rare medical condition that causes the body to produce an oversupply of breastmilk.

"In a typical breastfeeding journey, there's a cycle of hormones produced that produce the prolactin that makes milk supply," she explains to PEOPLE. "In my case, I have an enlarged pituitary gland and it secretes far above what is normal."

"With this ridiculous excess of prolactin, my body will just make milk on its own. And if I'm not pumping to relieve the pressure or the supply that my body is making, then things start to happen like tissue inflammation or mastitis or developing abscesses," the Oregon mom continues.

Anderson-Sierra — who recently set the Guinness World Record for the largest donation of breast milk by an individual, donating 1,599.68 L. (over 420 gallons) — was a full-time student and new mom when she was diagnosed, and had little idea of what the implications of the syndrome would be.

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"I was first officially diagnosed in the spring of 2015, but I started displaying signs and symptoms of hyperlactation syndrome in the summer of 2014 during the pregnancy of my firstborn," she shares. "It was a lot to get a handle on. Not only was I a brand-new mom, but I also needed to learn how to use breast pumps and find a pumping schedule."

Elisabeth would quickly learn that pumping to meet her needs would take a lot of time away from her family and day-to-day life.

"I didn't realize how much I would need to completely change my lifestyle to be able to accommodate the syndrome," she says. "In the beginning, the time spent doing everything that needed to be done was significantly longer because of what was available as far as equipment and technology at the time."

Elisabeth also later learned that the syndrome qualified as a disability, "Because of how much overall time it takes, especially in the beginning."

"I was pumping about eight to 10 times per day and each pumping session could be about 45 minutes to 60 minutes. Just pumping alone is equivalent to a full-time job, and that does not take into consideration things like washing and sterilizing equipment, bagging and freezing milk," says the mom, who has donated approximately 350,000 oz. overall to date.

"And at the time, the equipment that was available — it was not like there was a mobile option. I usually had to just stay home to pump because that's where my equipment was."

There was plenty of equipment, with Elisabeth owning upwards of 14 sets of pumps, going through a pumping bra each month, countless supplements and expensive groceries, and 30-40 storage bags each day.

"Insurance only covers one set of components and because I was pumping so many times per day, I couldn’t wash and reuse over and over. Having to do that after every pumping session and wait for it to dry and sterilize would be a never-ending cycle."

And while no one piece was particularly expensive, the items, especially the storage bags, add up. "If you had to go buy ziplock bags at that rate, for example, you know, everything really adds up."

"You know how teenage boys can just consume and consume? I can 100 percent challenge them to an eating contest because feeding moms can go through so much," she says. "And between the food and the milk, there's also purchasing freezers in order to store everything, and the electricity bill that goes along with that. Plus water usage to wash and sterilize things all the time. It can cost hundreds, if not a thousand more per month to have this medical condition."

Finding a silver lining has helped Elisabeth push through the tough times. She has helped countless families in her area through milk donation.

"I first learned about milk donation while I was still pregnant with my first," she says. "I had previously been a blood donor with the Red Cross but since you can't donate blood while you're pregnant, I learned about milk donation. I've always appreciated and enjoyed being able to give back to the community and participate in the community."

"I donated milk after the birth of my firstborn to a local birthing center that handles some of my maternity care. It was neat because I was donating milk to people in our circle and could help bridge the gap for clients who would give birth and their milk wouldn't come in right away instead of them having to supplement with formula."

"And then from there, I still had so much milk so I also donated outside of the birthing center into the local community, and then also applied at a milk bank that supplies preemies and micro-preemies specifically, in order to support our tiniest little heroes."

Though Elisabeth and her family adapted their lifestyle to accommodate the syndrome over the years, she's been thrilled to recently return to having a "family lifestyle," with the mom finding independence in Baby Buddha's portable breast pump.

"Prior to using the Baby Buddha pump, there were few mobile options on the market. Typically you have to use a large hospital-grade pump that plugs into a wall, there's no battery. They're about the size of a basketball, so it's completely obvious and heavy and bulky," she explains.

While Elisabeth tried a number of pumps, "I definitely wanted to try and expand on what mobile pumping could be like."

"Nothing was ever strong enough until the Baby Buddha pump came out. It was smaller than anything that had been out previously and it measured up, even surpassed, what I need to support my pumping journey, " she shares.

"I can look at my pumping journey and see a complete overnight transition to where I was like this pump is able to accommodate my needs in every way possible and now I can do anything," she says. "I don't have to stay home, I can go to the park and not worry about having to get back home and plug in and pump or constantly being worried about being stuck in traffic or not being able to be home in time or an appointment runs late."

"It was just so easy to bring my equipment with me that we started going on family drives again. We started going to the beach again. We started doing all of this stuff again and I literally felt like I was able to live my life again," she says.

"I haven't pumped on a roller coaster yet, but short of that there's nothing I can't do. I've pumped on a family trip to Disney World and I've pumped during live concerts and in the movie theater, because I want to see things in the theater, too," Elisabeth celebrates.

"I want to experience these things and go out with my friends and I didn't want to be hindered by this medical condition and this pump is really the thing that turned my life around."

Elisabeth's family has also seen the difference in their lifestyle. "My parenting style is very open and educational, so they have always been involved and know all about pumping," she explains.

"They could totally assemble anything that I need also. They also know that it could be dangerous and so they know to look out for things like if their dad is at work and my blood sugar is crashing," she says, recalling a recent incident.

"Just two or three days ago, I hadn't eaten enough soon enough. As I was heating something up in the microwave, I passed out and fell to the ground. And so they know what to do in an emergency situation like that," she says. "It's important, I think for me, to be open about it with my children, but also my friends and family so that if an emergency arises, they know what to do and how to support it."

"There's a lot of negatives but I do try and focus on the positive. I've been able to provide breastmilk for my kid and continue to for my son, and I have the ability to share it and make a difference in the lives of others" Elisabeth, mom to Benjamin, 7 months, Sophia, 6, and Isabella, 8.

"With a lot of my local recipients, I have great relationships. Our children have playdates, we get invited to birthday parties ... we're just involved in each other's lives. And while it might be a passing stage of motherhood for them, I feel kind of stuck, so it's nice to foster these relationships and see the recipients of the donated milk. I'll get the text from their parents with pictures and updates, even as they get older."

Elisabeth notes it's hard for some people to understand why and how she does what she does, noting some people "think it's an 'I've done this to myself' kind of thing."

"That's not the case. My body just won't stop. I had tried a few medical routes already and while we were seeing some successes, the side effects were too much to continue with those treatment plans," she says.

As for the future, "one of the options is getting a double mastectomy to remove the actual tissue that creates breast milk. I will still have a lot of prolactin in my body, but it wouldn't affect the tissue receptors that harness it to make more milk."

"If I’m being really honest, I think I'm a little terrified. I already know how my body has reacted to the medications route and the side effects can be so dangerous. I have three kids, I have a husband, I have a full life and there are risks to everything," she says.

"But also to go through with the surgical route, then I would be physically different on the other side and so I think that If it's like a process of maybe acceptance. And maybe my whole journey with this condition has kind of been that — a process of determination and acceptance as things are coming my way."

She continues, "Finding that courage and determination to pick myself up and keep going, to try and show up and do my best. The same thing is hopefully true of the end of this journey, even though it's not here yet. My son is 7 months and nursing, so I think that once he's weaned I would start to consider my options, and most likely a double mastectomy, more seriously. I do have some time to research and wrap my head around that and what it will look like on the other side."

Despite the mixed feelings surrounding her own situation, Elisabeth is determined to help other moms show themselves more grace in their own breastfeeding journey.

"I look at my story as this unicorn case and I've seen moms who look at what my body produces and feel bad about what their body produces. I'm very vocal about the grass not being greener on this side," she says.

"I really would not want anyone to have this condition. You might say that you want all of this milk and that would be great, but you really really, really, really don't. I really stress and encourage moms to not compare journeys. We are all so unique and whatever your body is making is perfect for your journey. Every drop counts, every ounce matters. I encourage mothers to love their journey, no matter what it looks like."

As for her new Guinness World Record, Elisabeth says, "it's maybe just barely growing on me."

"I'm not used to it, that's for sure. I'm very humbled to hold it, but I'm still getting used to it. It's a great visual representation of what I've done and am still doing," she shares.

"I would just want to speak out for a bigger message, of normalizing milk sharing and donor milk. We've had a significant formula shortage lately and more mothers are pumping and producing an oversupply, but not knowing what to do with it. If you have extra to share within your community or to a milk bank, I think it would definitely help with the current formula crisis."

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