This week, the day before my son turns 2 months old, I’ll donate my 1000th ounce of breast milk. While I’ve always been a breastfeeding advocate, it wasn’t until my freezer began to overflow with stored milk that I started to learn about the ins-and-outs of long term milk donation.

Most women begin producing small amounts of colostrum around the 20th week of pregnancy. Two to four days after birth the colostrums begins to transition into milk. While regulating milk production in the early days of new motherhood can require some work, most women find that their supply has “evened out” and they make just the right amount of milk for their baby by six weeks post-partum. Though most women are able to produce just the right amount, some struggle to produce enough and some, like me, make a whole lot more than their baby could ever drink.

My little guy was born at 38 weeks, perfect, round and chunky. At 9 lbs 13 ozs he drank more milk than most newborn babies but still I found myself engorged morning, afternoon and night. While pumping excess milk can lead your body to continue to produce the excess, not pumping can lead to significant discomfort and, sometimes, breast infections like mastitis.

And so, uncomfortable and worried about mastitis, I began to pump. I carefully followed the lactation consultant’s instructions on pumping in an effort to avoid long-term oversupply and, over the past 8 weeks I’ve been able to reduce my supply significantly.

Still though, in the early weeks of my son’s life I was pumping 60-70 ounces of milk on top of what my little guy was drinking (enough for about 2.5 extra babies) and now, with a slow back down I’m producing 30-35 extra ounces per day (enough for about 1.5 extra babies.)

At first, I stored my extra milk in the freezer, pumped (see what I did there?) that I would have a freezer stash for when I headed back to work or if I ever found myself needing to pump and dump due to medication or other circumstances. After my freezer reached capacity I brought a few coolers full to my parent’s house.

I was comforted that they, living 100 miles from me, would have a backup stash for my boy should my power ever go out or my freezer break. After both of our freezers filled I began to research what to do with my extra milk. It was then I stumbled upon a few milk sharing facebook pages that allowed moms to reach out with requests for, or offers of milk.

I quickly found a mom who’d had twins the month before my son was born, who was struggling to produce enough milk for her babies. She wanted to avoid formula, as her babies had struggled with digestive issues, and she was hopeful that in time she would be able to boost her supply enough to provide them with her breast milk alone.

Since connecting with her I’ve donated 600 ounces of milk to her babies and another 350 to another mom I connected with online. Here’s what I’ve learned about the etiquette and niceties of a milk sharing relationship.

If you’re donating milk:

Know your milk storage guidelines and stick to them

When you’re donating milk it’s important to closely follow the strictest reading of the milk storage guidelines laid out by La Leche League. Freshly pumped milk should be left at room temperature for no longer than four hours, in the refrigerator for no longer than three days and in the freezer for no longer than three months. Ideally, milk should be pumped, poured in milk storage bags and frozen immediately.

Label your bags

Each bag of pumped milk should be labeled with the date, the number of ounces, and the time. Knowing the date that milk was pumped helps the recipient mom know which milk to feed her baby first. Knowing how much milk is in the bag allows the recipient mom to plan ahead and send the proper amount to their caretaker if necessary. Labeling bags with the time can help the recipient mom match up “night milk” with night time feedings, which is important, as breast milk changes composition throughout the day.

Be open about your diet, medication use and anything else that may be relevant

Some babies are allergic to dairy. Some are sensitive to soy. Others react badly to spicy food or root vegetables or caffeine. When you donate milk it’s important to be very open and honest with the mom you’re donating to about anything that goes into your body. If you find yourself in a situation where your diet or lifestyle doesn’t match up with the desires of the mom you want to donate to, it’s likely best to find a different family.

If you’re receiving milk:

Be open about what you need

The only way you’ll be able to find a donor mom with a lifestyle that meets your needs is to share exactly what those needs are. Even if you feel it sounds picky to ask for milk from a vegetarian, alcohol-free, dairy free, medication-free mom, if that’s what your baby needs you should share this information from the onset.

Offer to replace storage bags and pump parts

Pumping is hard work. Buying extra food to ensure a mom is able to continue to produce milk is expensive. Washing pump parts, labeling bags and storing milk takes time. While donor moms aren’t interested in being paid for their milk it is extremely helpful when recipients replenish milk storage bags and pump parts as necessary.

Doing this simply offsets the true cost of providing milk to another baby and shows your donor mom that you appreciate her hard work. If you’re not sure what sort of pump parts or bags your donor uses, a gift card to a store that sells pumping supplies is generally appreciated.

Work around your donor’s schedule for pick up

Since the donor mom is spending a great deal of her time pumping, it’s generally appropriate for the recipient mom to adjust her schedule as needed to accommodate pick-up. While many pairs are comfortable meeting somewhere in the middle, its good practice to offer to come wherever is convenient for the donor mom at a time that’s convenient for her.

Good luck to all the milk sharing mamas out there!