It is not the years of marriage, but the sex on the right time will make you conceive. You are most likely to conceive if you have sex one or two days before you ovulate. So have sex during your fertile window, which is lasting up to six days a month. These six days are the five days leading up to, and the day of, ovulation, when your body releases an egg. Remember sperm can survive for up to a week and egg will survive for about a day once released. So it is tricky to find out when you are ovulating... The best way for this is just simply have sex every two or three days. If you have a 28-day menstrual cycle, you may likely ovulate around the middle of your cycle. If you have a short cycle, you could ovulate within days of your period ending. A long cycle, you won't ovulate until two weeks after your period has ended, so it depends on the duration of your cycle. You can use a free online ovulation calculator to calculate ur ovulation if you want ... i suggest you the best of of counting all this is just have sex every two days and not conceiving after all this you both need to seek medical attention to rule out any abnormalities. you never mentioned your age, duration of period, how often u have sex etc, which could have been of helpful for a suggestion. Good luck....