For some it works, my cousin was trying for 7-8 years and then she stopped trying and immediately fell on, she has PCOS and was putting herself under so much pressure tracking everything. She warned me to not to try and just enjoy having sex and spending time with my OH. It was the same for my mum, she tried for 6 years with me almost had IVF and then it was putting a strain on her and my dads relationship so she gave up on the thought of a baby and then fell on immediately.
If the thing your doing now isn't working, change it up, enjoy sex and see what happens. Everyone's different so what will work for one, won't work for another.