Had a miscarriage and haven't been able to conceive since...

I am 34 and have two sons 8 and 4 from a previous marriage. My husband is 34 and has a 11 yr old daughter from a previous marriage. We have been married since June 2015. We tried conceiving in December of 2015 and got pregnant right off to our surprise. However, we had a miscarriage in February 2016. We haven't been able to get pregnant since then. With my past pregnancies I just got off birth control pregnant never tracked anything. We would love to have one more child. Tips? Ideas?