Generally speaking, 60-70% of couples will become pregnant after six months of trying and 80-90% of couples after 12 months of trying. But your chances of falling pregnant decrease with age. This is true for both partners, but more so for the woman than the man. A woman produces one mature egg per month (if there is regular ovulation) and this egg will only survive 24 hours. As you age, the quality of your eggs may also diminish, making it even harder to get pregnant.