Tuesday 4th December is the Roman Festival of Bona Dea, this being a smaller festival that the one celebrated on 1st May but similarly for women only. In Roman mythology, Bona Dea (literally "the good goddess") was the goddess of fertility, healing, virginity, and women. Image left of Roman girls playing is from Wikipedia and is attributed to Agnete [GFDL or CC BY 3.0], from Wikimedia Commons.
She was the daughter of the god Faunus and was associated with supplying medicinal healing herbs in her temple garden. Bona Dea was also invoked for freedom from slavery; many of her worshippers were freed slaves and plebeians, and many were women seeking aid in sickness or for fertility. Her oracles were revealed only to females.
Men were not just prohibited from Her secret festival, they not even allowed to know Her name, let alone utter it. There were other restrictions during the worship of Bona Dea: drinking either wine or myrtle was taboo and could not be mentioned by name throughout Her secret festival, probably because they were both considered very powerful due to their sacred association with Her.