Can you tell me how the phrase...

An old wives’ tale is a foolish story told by a garrulous old woman (according to the dictionary). Most of these tales offer some sort of advice and have, over the centuries, become part of folklore. Thus, there is at least one tale, and sometimes dozens, for just about any situation. In the case of pregnancy and birth, here are a few. Conception: A couple that goes to the movies within three days of getting married will have twins. Gender: A baby conceived in the light of the Moon will be a boy; in the dark of the Moon, a girl. Birth: Labor pains can be eased by putting an ax under the bed.