Thread by @richardbuka

It's world breastfeeding week! #WBW2022
As a haematologist, the most common involvement in breastfeeding is with post-partum anticoagulation advice. DOACs have revolutionised treatment of thrombosis but @ISTH recommend they are avoided in breastfeeding. 1/

But...
I wonder whether this is sometimes interpreted differently. Is it instead interpreted as:
"Breastfeeding is best avoided on DOACs"?
I wonder... are women are put off, or worse - are HCPs advising not to breastfeed so DOAC can be used, avoiding warfarin or injections? 2/

Breastfeeding has so many advantages for mum, baby, and for society but it is not well understood by HCPs. (ncbi.nlm.nih.gov/pmc/articles/P…) so I really worry that this might be the case. The harm that can result from a woman who wants to breastfeed and is told she can't can be huge. 3/

So, are DOACs dangerous in breastfeeding, or could a well-informed doctor work with a well-informed patient to come to a well-informed, evidence based decision?
4/

DOACs are present in breastmilk in varying amounts: dabigatran the least, apixaban the most. For dabigatran, absolute infant dose would be <10% of the maternal dose - a level the FDA deems acceptable although exposure could be higher in first 10 days. pubmed.ncbi.nlm.nih.gov/33963877/ 5/

Safety data is always going to difficult to get as breastfeeding women are unlikely to be in trials. Unlike pregnancy, accidental exposure is unlikely as although you can not know you are pregnant, it's quite difficult to be oblivious to the fact that you're #breastfeeding 6/

Several published trials have looked at DOACs in children and have found them to be safe and effective but include small numbers of young kids e.g. DIVERSITY trial of dabigatran <6 months: 14, EINSTEIN Jr trial of rivaroxaban: 37 <2y 7/

So, very limited data regarding safety in very young children but probably safe. Therefore, dabigatran should be safe in breastfeeding?
But are there any black swans? Do we need to think about other adverse effects other than just bleeding? 8/

Coagulation, inflammation, immunity are all intertwined. There could be developmental adverse effects associated with drug exposure especially very early in life. We have to be very careful 9/

So. In conclusion, in my humble opinion. If a new mother needs anticoag, discussion should be very sensitive re breastfeeding.
HCP should not say "if you don't breastfeed you can have a tablet and that will be much easier". 10/

We should be explaining benefits of breastfeeding. Haematologists should have good knowledge of breastfeeding, and an understanding of how important it is to some mothers as well as the benefits and the barriers. Options of LMWH or warfarin are workable and safe. 11/

For a great introduction to breastfeeding, I recommend this free book from Patricia Wise @wbtiuk (as a PDF): …eastfeedingtrends.files.wordpress.com/2019/10/suppor… 12/