Ihave never breastfed any of my three daughters. When I had my first daughter, Mekayla, in South Africa 10 years ago, no one expected me to breastfeed, including my consultant, who said that using formula was just as good.

My attitude changed when I miscarried twins in 2012. Losing them was so hard and even though I know I couldn’t have done anything to prevent the miscarriage, it made me determined to do anything I could to help my children.

By this time we were living in Scotland, which has a very different attitude to breastfeeding, but I was still a bit squeamish and didn’t like the idea of doing it myself, though by now I was aware of its benefits. When I became pregnant with our daughter Sarah a year later, I decided to try to express my milk and feed her from a bottle.

It seemed the perfect solution, but one of the midwives caring for me was unhelpful, telling me it would be difficult to express milk if I wasn’t actually breastfeeding. When I got annoyed with her, she apologised and backed off quickly, but I guess that made me even more determined to feed my baby the way I wanted – especially since Sarah was thriving. Mekayla has had digestive problems since she was a baby but we’ve had nothing like that with Sarah. By the time Sarah stopped feeding, I had a freezer full of expressed breast milk which I ended up throwing out because didn’t know what else to do with it.

When I was pregnant with Paige (who is now six months old) I read about the donor milk bank at an antenatal clinic and was instantly interested. I learned that nearly 4,000 babies are born prematurely in Scotland every year; because their organs and immune systems have had less time to mature, they’re at greater risk of infection, which can be fatal in their critical early days. Breast milk is often the only thing a very sick or premature baby can tolerate, but mothers with a shortened pregnancy often find that their milk has not yet come in. I knew I could express plenty because of my experience with Sarah; the thought of helping other tiny babies and their worried mums meant a lot to me.

I contacted the coordinator of the donor milk bank and she made it really easy, coming to my house to do my blood tests as part of the screening process and talking me through the process, so I was good to go. But then Paige was born a month early and in special care for a couple of days. That’s when we saw those tiny babies who could fit in your hand, only managing to take about 4ml of milk at a time – and  the reality of milk donation hit home. Paige was in special care only as a precaution, but watching those other parents desperately hoping for their babies to survive, and realising I could help, was when the feeling that I should become a milk donor changed to wanting to do it. My partner, Alfie, and I had lost two babies and experienced that pain and now I knew I could make a real difference, helping to keep other people’s babies alive.

I now spend about six hours a day expressing milk, which I do four-hourly; I also get up at 2am to express ahead of Paige waking up at 3am for her night feed. I don’t find it uncomfortable, and the more I express, the more milk I produce.

The milk is frozen and then picked up every week by one of the volunteer drivers. I’ve been told I’m donating record-breaking amounts, and I’ll carry on donating for as long as I can, especially since I’ve now got into such a good routine.

Some people are surprised by it, especially as I don’t technically breastfeed my own baby, but it’s just what I do now, while I can. If I’m tired, I just think of those babies in special care and their parents’ gratitude for every single drop of milk that is donated. Six hours a day for 10 litres a week doesn’t seem that hard.

• As told to Joan McFadden.

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