A woman in the US has had her memory erased through having sex with her husband (that bad, huh?).

Immediately after she finished doing the deed, the 54-year-old was admitted to Georgetown University Hospital unable to remember the past 24 hours.

Experts say this rare condition is known as 'transient global amnesia' and is often triggered by sex or other physically vigorous activities.

It only affects about 3 to 5 people per 100,000 each year, and it's usually just people in their 50s and 60s that experience an episode.

Fortunately (or unfortunately – were it forgettable sex) the memory problems usually reverse themselves in the space of a few hours and there are zero side effects.

The 54-year-old's brain scans showed nothing unusual and by the time she left the hospital her memory had almost completely returned.