Regulate period after IUD

Looking for some advice as I have never been on birth control so not sure how to help.

My best friend is trying to get pregnant. She had been on birth control for 10 years then last year got the IUD placed. She had it removed 3-4 months ago and she hasn’t really gotten her period back. Spotting here and there. So not regular at all.

She is wanting to get pregnant and it’s just not working. Does anyone have any advice or things she can do/take that can help get her period to return and be more regular?

She is young and no underlying health concerns.