WHY DO MEN PREFER 'MORNING GLORY' WHILE WOMEN GET FRISKY AT NIGHT

Blokes tend to wake up feeling amorous, while their partners get in the mood late in the evening - so why can't we synchronise our biological clocks?

Why is it that a man feels at his sexiest when he wakes up in the morning but a woman wants to go back to sleep?

And why, late at night, when a woman is in the mood for love, is her man just lying there, snoring? It all comes down to hormones. Here’s why our sex clocks don’t always tick in time.

5am

Even before a man has opened his eyes in the morning, his level of testosterone is at its peak – between 25% to 50% more than at any other time of the day.

That’s because the pituitary gland in his brain – which governs the production of the male sex hormone – has been switched on in the night and levels have been steadily rising until dawn.

Women also make ­testosterone – the main sex drive hormone – but produce a fraction of the amount and it rises by only a tiny bit overnight. It is also kept in balance by oestrogen and progesterone.

“Men need only a normal amount of testosterone to feel like sex,” says Ashley Grossman, neuroendocrinology professor at St Bartholomew’s Hospital, London. “The raised levels in the morning means most men will wake up two to three times a week with erections.”

6am

Slept well? A good kip is another reason a man may feel even more amorous in the morning. Studies found the longer and deeper a man has slept, the higher his testosterone levels. Research in the Journal of the American Medical Association shows getting more than five hours’ sleep can raise male levels by an extra 15%.

7am

While a man’s levels of sex hormones are at their highest when he wakes up, a woman’s are at their lowest. “Male and female testosterone levels are at their highest at opposite ends of the day, so they are out of synch,” says consultant gynaecologist Gabrielle Downey, of the Sandwell and West Birmingham Hospitals NHS Trust.

“It takes more than hormones to get a woman in the mood, so men need to make an active effort.”

Instead, women’s hormones rise and fall more over their monthly cycle than through the course of a day.

At their height – midway through her cycle – a woman’s levels of testosterone will be 30 times higher than at the start.