Is it true that fennel seeds can increase your breast milk supply?

If you check kellymom.com, a breastfeeding website, it says that fennel is related to digestive problems. I didn't try it when I was breastfeeding (I took fenugreek and malunggay instead), but like with anything all of us mothers take to try to increase our supply, there are possible side effects. It's safe to take fennel in so far as it won't cause extremely serious health issues, but yeah, there's a risk of experiencing some tummy problems by taking it.