I thought about this a bit more, and here's some information that I found or remember having seen:
Here's the website to the company that manufactures the brand that I take, where they say that it is safe for pregnancy and BFing:
http://naturalfactors.com/ca/en/products/500/dgl-deglycyrrhizinated-licorice-root-extract
Of course, they are a company selling something, but I would hope their liability lawyers would keep them from posting that if it's not true. If you don't want to rely on this alone, you could maybe call them and ask for the research references that they used to determine that DGL was safe for BFing?
And I also remember that DGL was recommended in the book A Natural Guide to Pregnancy and Postpartum Health - one author is a doctor and the other a chiropractor - you can look it up in Amazon, and click on look inside this book, and then search for DGL to see some excerpts. They specifically recommend it for pregnancy and postpartum, and while they do not specifically address BFing, I feel that they would likely mention if BFing were a problem with this herb since the whole book is about postpartum health, but of course that's just my opinion, and it's possible the authors overlooked this issue.
Hope this possibly helps!
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