I Am 29 Yrs Married Lady.My Hus Is 30 Yrs.

I am 29 yrs married lady.My hus is 30 yrs. We are trying for a baby last two months. my period was almost regular before.I started folic acid 3 months before.But now this last 3 months my period irregular that is more than 40 days. I did all tests that is thyroid,prolactin,ultrasound etc. all normal.
Then what I want to do, can I continue folic acid until become pregnant?