TTC for 6 months- dr said everything is perfect and we have sex like 4-5 times a week. Always! Why no baby?

So we conceived my son while I was on BC in 2012 and have been trying for a second since May. I went to the doctor to see if everything was okay and she gave me the green light. Everything is perfectly fine. So what's the issue then? We have sex 4-5 times a week all the time and I don't understand what else might be going on. Is anyone else in this situation or have conceived after going through a similar situation? I haven't used birth control since before I was pregnant last time (we have used condoms when near ovulation). Any suggestions?

I have two glasses of wine like 3 times a week with dinner. Maybe that??? IDK...