My Husband And I Are Both 27, Married For 13

My husband and I are both 27, married for 13 months now have never used contraception but never actively tried to get pregnant by tracking ovulation either. We started trying this month but I'm concerned because he's diabetic and was diagnosed when he was 14. He had been careless about taking lantus after marriage but has bee careful and keeping it under control since 3 months now but he doesn't exercise and smokes.