Maithuna or sex is one of the vital basic needs of life. It is otherwise called Grahysthya Bramhacharya. Lots of guidelines have been described regarding fair maithuna (sex). Lots of contradictions have been fixed for maithuna.
Maithuna should remain within limit so that it cannot destabilize the physical and mental state. Favourable situation for maithuna is highly emphasized in Ayurveda. It is advised to have maithuna on every 3rdday in vasanta (spring season) and sarata (Autumn season) ritu, with a gap of a fortnight in rainy and summer season and according to own interest in hemanta (Dew) and sisisra (Winter) ritu.
After maithuna bath, moon bath, milk, non-veg soup, wine, juice, sleep are advised. Age of the partner should not be less than 16 years or more than 70 years.
Many more have been described regarding maithuna. Maharshi Vatsayana, Charaka, Sushruta, Vagbhatta have written a lot over it.