I was on metformin while I was pumping. I was getting 6 oz a day at 4 months of pumping. Metformin actually can help increase breast milk.
I gained a ton of weight on the protocol, but it was from the yasmin, because once I stopped the bc I lost 20 lbs!!
I've tried emailing Lenore a few times in the past 3 years for various things that I couldn't find on these boards or online, but she never responds. Jack Newman has always reponded and VERY quickly. I'd ask him if you still have questions.