Two loving people can be great partners during the day. But when the head hits the pillow, that connection can break. Research in labs with wearable trackers shows that couples who share a bed wake up more often. They also sleep less efficiently and get less total sleep than when they sleep apart.

Yet about half the pairs feel they sleep better together. Emotional safety, habit, and pressure to be a "good couple" play a big role in shaping these feelings.

So how can you dial up both sleep and sex without sacrificing either? Well, you can see sleep as the master dimmer switch for every hormone that makes sex enjoyable.

• Five nights of 5-hour sleep will tank a man’s testosterone to the level of someone a decade older.
• Similar sleep restrictions affect key female hormones like FSH, LH, and progesterone. This can reduce libido and physical sensation.
• Each extra hour a woman sleeps boosts her desire to have sex the next day by about 14 per cent. That comes close to the boost from prescription libido drugs.

Good sleep primes the body for better sex.

THE CLIMAX

Intercourse that leads to orgasm boosts self-rated sleep quality by 60–70% for both men and women. Solo sessions still clock a ~50% improvement. Climax causes a quick rise in sympathetic activity, which triggers fight or flight. This leads to a racing heart and higher blood pressure. A sharp drop in parasympathetic (rest and digest) activity follows this.

Together, these changes help you fall asleep quickly. Oxytocin and vasopressin then flood the brain, lowering cortisol and quietening emotional circuitry.

DOES SHARING A BED BACKFIRE?

"Sleep divorce," or sleeping in different rooms or beds, is becoming more popular. For many, avoiding a partner's snoring or duvet tugging leads to more sleep and a better mood. This should create a warmer attitude towards each other the next day. But others find that distance at night feels lonely or dampens spontaneous intimacy.

If separate rooms don’t work for you, try the Swedish setup. One double bed and two single duvets. This should put an end to the nightly tug-of-war, at least.

Technology is also helping. Some new bed brands, like Eight Sleep, have made a base that adjusts on its own. This base moves to reduce snoring as soon as it detects it. It also cools and heats both sides to improve sleep for you and your partner.

A sleep divorce doesn’t mean sleeping apart forever. Even when used a little, it can help both partners sleep better and stay in harmony. This is especially true when their natural sleep times and chronotypes differ a lot.

So, will sleeping in separate rooms lead to more sex? Only you can decide that. Biology loads the dice in different ways for men and women, but the house rules remain unchanged. Consistent, high-quality sleep is the cheapest aphrodisiac either sex can buy.