In 1873, it became illegal to advertise anything to do with birth control devices in the US. This was based on the Comstock Act, which not only prohibited advertising but also distributing birth control.
The law also allowed the postal office to confiscate any items sold via mail. In order to avoid being penalized for advertising and giving information related to birth control, marketers used alternative terms instead such as “marital hygiene” and “feminine hygiene” to sell their products to the masses.