Found this on the web, someone discussing this very subject.
**broken link removed**
IMO the rewards for the mother using the GH nowhere offset the potential risks to the child. Not something to experiment around with. The mother needs to wait unitl she is done breastfeeding. Most women dont end up breast feeding that long anyhow. My wife made it about 10 months on my first daughter and 12 months on our second, and most women dont make it nearly that long. Just have her wait, or if she feels like she cannot then she needs to stop breastfeeding and go to formula.
If she wants to use the GH to get lean let her know that breastfeeding is one of THE BEST ways for new moms to lose weight. Producing all that milk takes a lot of calories. The more the baby drinks the more milk she will make and the more calories she wil burn. My wife lost her weight fast just breastfeeding and eating right. No exercise was even needed.