Dr Marilyn Glenville claims one sex position, more than any other, will boost a couple's chances of getting pregnant
As sex positions go, missionary is probably considered the most traditional.
But if you're trying to get pregnant, it's the way to go.
At least that's the view of fertility expert Dr Marilyn Glenville.
Increasingly, couples are waiting later to start families, choosing instead to focus on their careers in their 20s and 30s.
But as women hit their fertile peak between the ages of 23 and 31, one in four couples now have problems conceiving.
So, they need all the help they can get.
Improving your diet, abstaining from drinking alcohol and avoiding caffeine will all help your chances, say experts.
However, Dr Glenville says your choice of sex position plays a part, too.
She told Daily Mail Online : "The man-on-top position has the best chance of getting a woman pregnant.
"The rationale is that this position allows for deep penetration so the man's sperm can be ejaculated as close to the cervix (the opening of the womb) as possible."
"This gives the sperm cells a flying start on their long journey."
Although there is no scientific proof backing Dr Glenville's claims, she offers an explanation, saying the closer the sperm cells are to the egg boosts their chances of reaching it.
Citing logic, she says that any position that "goes against gravity" - the woman on top, or having sex sitting or standing up - will "discourage" the sperm's journey.
Another option is the man entering the woman from behind, with her kneeling in front of him and her bottom higher than her head, according to Dr Glenville.
However, 'spooning' is a no-go because the "penetration angle is not so deep".
Other experts, including biologists Robin Baker and Mark Bellis, claim the woman's ability to orgasm can make a difference when it comes to conceiving.
