From a selection of sexual taboos from the Encyclopedia of Sex and Gender, excerpted by Vaughan Bell:
In some societies, sexual activity is prohibited during certain times of day. The Cuna of Panama approve of sexual relations only at night in accordance with the laws of God. The Semang of Malaysia believe that sex during the day will cause thunderstorms and deadly lightening, leading to drowning of not only the offending couple but also of other innocent people. And the West African Bambara believe that a couple who engage in sex during the day will have an albino child. … The Ganda of Uganda forbid sexual intercourse the night before battle if the fighting is likely to be protracted. The Lepcha prohibit sex for three months after a bear trap has been set. If the taboo is broken, no animals will be caught.