6-Mercaptopurine & Breastfeeding

[magichandles]

I'm currently 23 weeks pregnant with DC3 and taking 50mg of mercaptopurine (6MP) a day. Has anyone successfully breastfed on this and at a similar dose?

I FF DCs 1 & 2 - DC1 was 6 weeks early and I was basically told "the book says no" when I wanted to breastfeed her and I didn't have the mental or emotional strength at the time to delve into it further and just accepted it for DC2 as well.

I've read some anecdotal things online, mostly from the States, that women have been "allowed" or have successfully BF on similar doses. I feel that I should really try and give it a go this time as I feel pretty guilty that I didn't BF either of my previous DCs.

Have a look on lact-med, they've usually got a good idea and there's a pharmacist called Wemdy something that specialises in breastfeeding & medication. Google should find her if someone with a better memory doesn't come along soon

Wendy Jones from the BFN - she has a Facebook page. BFN also have a drugs in breastmilk helpline you can call.

Thanks, I shall have a look at those, although a quick look at Lact-med looks promising already.

You can pm me if you like, I bfed 3 babies for 12 months+ each, while taking azathioprine, which metabolises to 6-mercaptopurine.

In summary, the book will say no because nobody has done specific research on this kind of thing because of the ethical issues, and (with my cynical hat on) because it's a women's issue and therefore of minor interest, and it's easier just to say no.

The advice I received from my then consultant who had years of experience of prescribing this to women of childbearing age was that in practice they would assume that the benefits of bfeeding outweighed any theoretical risks. In practice he said the amount of active ingredient passing into the milk would be very small, and he'd never encountered any actual problems that could be attributed to the medication (this was over about 30 years of experience).

Having said that, it obviously isn't nice stuff, so worth trying to get reassurance from reliable sources. Confidence in your facts and sources is also important when you encounter medical staff who will tell you that you shouldn't be breastfeeding and your baby's immune system will be damaged for life etc etc. IME the confidence with which healthcare professionals offer these kinds of opinions is inversely correlated to their level of actual knowledge, but do be prepared for that.

Thank you frogs, that was pretty much my experience with DC1 - I was booked initially at a hospital with an obstetric physician who mentioned in passing that I would probably be able to breastfeed, but I might have a fight on my hands, but we went into no more detail as it was an early appointment. I then ended up giving birth at a different hospital where they had no direct experience, and as I said, just encountered a bit of a brick wall.

Did your children have to have blood tests while you were breastfeeding at all?

Nope, no blood tests. It was never raised as an issue (though obv I did have officious junior doctors coming in and telling me all sorts of things they half-remembered from medical school). I was on 150mg of azathioprine long-term, so throughout all my pregnancies and bfeeding periods. No idea what dosage of mercaptopurine that equates to, though.

Wrt medical professionals, if you don't have access to a consultant with long experience of treating women of childbearing age with that medication, then it may be an uphill struggle to get someone to rubber-stamp your choice. But if you can get good anecdotal support from people you find convincing, then tbh assuming you're not in hospital long-term, nobody's really going to know how you feed your baby, are they?

In any case, I'd have thought the risk of problems from breastfeeding would be minimal compared with the exposure in utero, and presumably they're okay with you being pregnant in the first place?

There's also Hale's breastfeeding and medication site which has lots of useful info.