Periods: Bottle Feeding Mamas

Chloe • Proud mama of twin girls 💕 Born 25.11.16
My LO's arrived a month early on November 25 and are now almost 4 months old. I have had one period since then, and am anxiously waiting another .... is it common for periods to become irregular after pregnancy? I would LOVE more children, but would also like my little girls to be at least 1 1/2 before another baby would come along.