Men have sex once a month if both husband and wife are healthy, sex coincides with the ovulation period is also easy to get pregnant, but due to the number of sex less chance of conception will be reduced; if any of the husband and wife suffers from physiological disorders, in the non-ovulatory period of coitus is not easy to get pregnant. The prerequisite for pregnancy is that the sperm and egg are able to unite and implant successfully. If the couple has intercourse during the woman’s ovulation period, and the quality and quantity of the man’s sperm are not abnormal, and the woman’s fallopian tubes are open, it is possible to get pregnant even if you have sex once, but the chances of conception will be reduced due to the low number of times of sexual intercourse. If one of the spouses suffers from diseases, such as abnormal quality and quantity of male sperm, female fallopian tubes, polycystic ovary syndrome and other diseases, it is not easy to get pregnant even during the ovulation period. If both spouses have no health problems, increasing the frequency of intercourse during ovulation can increase the probability of conception. If the couple has been married for more than a year and is still not pregnant, they need to go to the hospital for a checkup and should not use medication indiscriminately.