Having sex every day could help you conceive – but not for the reason you think

But a new study suggests there could be more to it than timing alone. According to the study, the more sex a woman has at any time in her cycle, the higher her levels of cytokines. These molecules reduce the 'foreignness' of sperm and embryos, and stops her body attacking them.

It's vital that the body has a strong immune system in order to stop sperm being 'attacked' or to prevent a fertilised egg from implanting into the womb, lead author of the report, Tierney Lorenz from the Kinsey Institute, says. He believes that frequent sex sends a signal to your body that it's ready to get pregnant.

"It's a common recommendation that partners trying to have a baby should engage in regular intercourse to increase the woman’s chances of getting pregnant - even during so-called 'non-fertile' periods - although it’s unclear how this works," he says. "This research is the first to show that the sexual activity may cause the body to promote types of immunity that support conception. It’s a new answer to an old riddle: 'How does sex that doesn’t happen during the fertile window still improve fertility?'"

However to say the study suggests daily sex increases your fertility isn't accurate. Instead Lorenz advises that couples do what's right for them in their relationship.

NICE (National Institute for Clinical Excellence) suggests couples trying to conceive have sex two to three times a week to up their chances of having sex at the optimal time – and to remind the immune system to be super-friendly to incoming sperm.

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