Hi, Though the number of ova starts dwindling with advancing age, 40 is not certainly late for conceiving naturally. First of all, you should undergo investigation to proclaim yourself fit to try natural conception. Tests for ovulation, tubal patency, male factor and hormonal imbalances are all necessary. Ovarian reserve needs to be counted considering your age. If everything is fine, you may give a try for about six months with regular intercourse monitoring the ovulation period. Aided reproduction may be needed after failed natural trial for 6 months, further delay would reduce your chances of conception. Hope this helps.