- Mild
- Both Scully and Mulder are occasionally seen in their underwear (which is quite ordinary and not very revealing).
- A woman is shown waking around the facility in the nude. Though her body is hidden by objects, it is clear that she is naked.
- There is a woman wearing very revealing mortal combat style clothing her entire butt is visible multiple times wearing only thong like underwear
- Lengthy and explicit discussion of sex abuse.
- Mulder flips through a calendar containing women in bikinis.
- Occasional mentions in dialog of pornographic magazines and videos. Nothing explicit is ever shown on screen.
- Certain episodes feature occasional sex scenes (actions, no nudity), in general once or perhaps twice per season. Characters on a few occasions in stages of undress, rarely though in a sexual nature (more sleeping, occasional bathing interruptions) and prostitutes occasionally crop up, as spies, information sources etc.
- An episode features a naked Neanderthal woman, though we never see any nudity beyond one quite distant hazy rear shot.
- An episode revolves around a woman who was raped by supernatural entities, she is shown thrashing around in a bed (fully covered) and later seen badly bruised and mentally scarred from the ordeal.
- An episode revolves around a family resulted from years of incest.