It shouldn't affect the time it takes to conceive. If you are a fertile mertyl then weeks after but if you had trouble then expect trouble again. I had mine taken out in may few yrs ago and was very careful but got pregnant in june anyway.
I have no idea how fertile I am; I was told I couldn't get pregnant naturally due to PCOS and I believed the doctors because I never got pregnant with my ex. However, 8 months into my relationship with the husband we were preggers. So, who knows.
I had my IUD taken out in August and just found out I was pregnant yesterday... so not long! But, I had the copper IUD which has no hormones, I heard the Mirena IUD can take up to a year to conceive. If you figure out when you ovulate it helps!