Sharing a bed with a partner can be problematic when it comes to high quality sleep. Most people have different sleep routines and habits. Women are more likely to be light-sleepers and are often more adversely affected by bed-sharing with a partner. Men as a rule often sleep more soundly with a companion. Reasons for this may lie in the evolutionary advantage of female alertness during the night for good child rearing and offspring protection.
There is also the issue of heat. Men are generally hotter than women. The basic general physiological differences between the sexes such as size, weight and bodily proportions affect the way men and women conserve heat.
Women typically have a higher ratio of surface area to volume, which causes a loss of heat. Men tend to have a greater muscle mass and this helps them to generate heat.
Even at rest, muscles produce around 25% of your body’s normal temperature, so more muscle mass means a greater heat production. It is believed that women evolved a system to protect their core body temperature against freezing weather — in response to cold surroundings, a woman’s body reduces blood flow to the skin and extremities to maintain their core temperature at 37C. This means that women are better than men at conserving core body heat when the weather cools.
Becoming boiling hot in the night, or getting a sudden chill, can cause sleep disturbances and this can manifest as nightmares or even night terrors.
Falling asleep in the arms of your lover can be bliss, but staying asleep with them all night long is often a different story. Dream content is less individual, and sleep quality is likely to be lower. You’re more likely to get disturbed in the night. For long term bed-sharers, it can often be difficult to fall asleep without their partner once a co-dependent comfort zone has developed. At the end of a long-term relationship, many people have great difficulty falling asleep alone. Learning to enjoy sleeping and dreaming alone, may help the individuation process.
It’s estimated that around 40% of couples living together, sleep in separate rooms. It may be the very best way to get the high quality sleep you deserve, especially if you are a woman.