Breastfeeding with hypothyroidism

[MrsAET]

Just discovered I have an underactive thyroid 4 months post partum. I have a history of thyroid problems, overactive pre pregnancy, normal during pregnancy, overactive for first few months and now underactive. Have seen the endocrinologist today but completely forgot to get advice on breastfeeding. I'm not being treated at the moment, got to wait another 8 weeks to see if it sorts itself out.

At the last weigh in DS had dropped from the 25th to the 9th and the weigh in before the 50th to the 25th. I am thinking underactive thyroid could be affecting the quality of milk supply and resulting in him not putting on enough weight. He's also waking more frequently in the night for feeds. So I'm wondering whether to introduce a formula feed to try and top him up. He takes a bottle well but I don't want to damage supply further by introducing formula. I don't want to stop breastfeeding but I want to make sure DS is getting everything he needs. HV advice was to try fit in an extra feed, but this was before I found out I was underactive.

Does anyone have experience of introducing a formula feed to increase weight gain? When would be a good time in the day to add this in?

I’ve not got any experience sorry but the night waking coukd be purely down to the 4 month sleep regression.

If you are worried about your supply and his weight, have you spoken to a BFC on one of the Bfing Helplines?

Was the Endocrinologist aware that you are Bfing at all? It just seems a bit odd that they haven’t given you thyroxine if you are Bfing.

Yes I explained I was breastfeeding and he just said he'd wait 8 weeks to see what my levels are then and make a decision.
That's a good idea, thanks. I'll phone the breastfeeding helpline tomorrow for advice.

Did you manage to call one of the Helplines @MrsAET? Kellymom has some good tips for increasing weight gain here

I have an under active thyroid and am breastfeeding. It doesn't have any affect on baby or quality of breast milk.

@jiltedjohnsjulie I did speak to them and they said top him up with formula. Said it could be milk supply or just genetics taking over as me and DH aren't very big. I've given him a 6 oz formula feed at 7 for the last 2 nights. It hasn't helped him sleep any longer but has been on top of breast milk so feels like an extra feed rather than a replacement. Still waking every few hours to feed which I'm fine with as want to feed him as much as possible. Thanks for your advice.

My thyroid levels dipped after birth and my milk dried up totally - stupidly I didn’t realise that’s what was happening and we had a terrible time.
Maybe go see your GP to check your levels.

I have an underactive thyroid but it hasn't affected my milk at all, even when my prescription ran out and I was without meds for nearly two weeks (kept forgetting to renew it, then forgetting to pick it up) but after I had my daughter I was most likely underactive too (was during pregnancy but the doctors didn't do anything about it) so not on medication at all and she did drop percentile levels a fair bit at the beginning and I supplemented for a while but was able to go back to EBF (except for when I wanted a break). I really think they shouldn't be waiting 8 weeks before giving you meds as you are breastfeeding, any chance you can ask for medication now?