During a full moon or eclipse a pregnant women must wear a piece of clothing that is red. This is to prevent the baby form being born with a cleft lip. The red color is supposed to prevent negative energy from hurting the baby.
My informant is a building engineer. He migrated to the United States form El Salvador when he was 16 years old. He grew up in a city in El Salvador. Lots of the folklore he has heard has come from his family.
He heard this from his mother and other female relatives.