Pregnant after having sex once during a cycle?

Has anyone gotten pregnant while having sex only once on a cycle? My husband and I have gotten pregnant twice and we had sex the whole week of ovulation and boom pregnant, we lost baby number one and got preggo with baby number 2 right away. It's always been easy for us. Well now he is almost 1 and we have been living with my parents for the last two months while we finish fixing up our first house we just bought! (Were almost done) So we haven't had much time or privacy for sex and have had to get creative with it. But we are ready for our next baby! Is there any hope for us? Even just having sex once each cycle?