My Menstrual Cycle Is Very Irregular. My Last LMP Was

My menstrual cycle is very irregular. My last LMP was October 16, 2016. This was after almost 5 months of no cycle. I also struggle with Hypothyroidism and am on 100mcg Levoxthyroxine. I am married and have a child. My concern is that my husband and I want to try for our second child and that the irregular cycle is a sign of infertility? Please help