Was acacia root used as a contraceptive by Africans in ancient times?
Ancient Egyptian documents say that acacia gum prevents pregnancies if mixed with plant fibres and honey to form a pessary, a device worn in the vagina. Modern studies have shown that rats fed the plant's leaves or seeds did not become pregnant.
However, Dr J. Worth Estes, a professor of pharmacology and a historian of science at the Boston University School of Medicine, is sceptical. Dr Estes was asked to help evaluate the science behind ancient medicines and argues that most acts of intercourse do not lead to pregnancies, so without very careful studies, it can be hard to determine whether a substance prevented a pregnancy or whether there never would have been a pregnancy anyway.