Chole, yes if your cycle always about the same every month can start trying 16 days before AF comes thru till you dont notice anymore CM. YOu can sometimes feel Ovulation pains that was the only time I though maybe I O'ed so I did BD those days. But not everyone can feel Ovulation pains middle of their cycle. So you need to estimate, if you start 16 days before AF comes, just BD every other day lor if not tracking anything, although I also didn't do so. I just did it as it comes, and went with the flow when my DH feel like it.
Labbittree, not sure, think it may be Feb, but mine is highly likely a Caesarian baby due to age, so have to choose about 1-2 weeks earlier usually gynae prefers earller easier for Caesarian.