Regular smoking and drinking can have an effect on pregnancy, causing the quality of a man’s sperm to drop, but it doesn’t mean that he can’t get pregnant. If a man and a woman have sex without contraception, and the man chooses to ejaculate internally, and the woman is ovulating, the chances of getting pregnant will be higher. To be precise, pregnancy is not related to smoking and drinking, just from the perspective of eugenics, it is recommended that men and women quit those bad habits during the preparation for pregnancy.