Mommas for those of you who are breastfeeding and on birth control what form of birth control are you using?

I plan to breastfeed once my little lady is here and I plan to get on birth control at my 6 week postpartum check.. I just cant decide what form I want.. I was on the IUD in 2015-2017 when we started trying for #2 and I keep going back and forth if I want another IUD or wanting to try another method. Thanks for any advice or input you breastfeeding mommas might have! ❤