For women suffering from back pain, spooning - a sexual intercourse position where couples lie on their sides curled in the same direction - may not be the best option.
According to a study from the University of Waterloo, Ontario, in Canada, spooning can actually be one of the worst positions for aggravating certain types of back pain in women.
The new recommendations follow on the heels of comparable guidelines for men released last month.
Traditionally, spooning was recommended by physicians to people with back pain because it was thought to reduce nerve tension and load on the tissues.
"But when we examined spine motion and muscle activity, we found that this is not the case," said lead researcher Natalie Sidorkewicz.
During the study, researchers used combined infrared and electromagnetic motion capture systems to track how 10 couples' spines moved when attempting five common sex positions.
The findings were used to create guidelines, which recommend different sex positions based on which movements trigger pain.
According to the guidelines, women whose back pain is made worse by arching their backs or lying on their stomachs should replace spooning with the missionary position.
Adding a low-back support such as a pillow could also help keep the spine in a more neutral position.
For women whose back pain is made worse by touching their toes or sitting for long periods of time, the guidelines recommend doggy-style sex.
The study appeared in the European Spine Journal.
