The 'orgasm gap', as it's known, has highlighted for years that men are more likely to reach climax while having sex with women, than women are with men.

Sounds unfair, but why exactly is this? A YouGov study last year provided some more insight into the disparity, comparing the chances of reaching climax between people of different sexual orientations.

Overall, three in 10 British women (30%) say they orgasm every time they have sex, including 11% who who enjoy multiple orgasms each time.

While a further one in four women (27%) say they orgasm on most occasions, this leaves a third who say climaxes only happen sometimes (15%), rarely (10%) or not at all.

In stark contrast to this, three in five British men overall (61%) say they orgasm every time they have sex, with another 23% reporting they do on most occasions. Only 10% say they do so sometimes, rarely or never.

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Comparing the data across two surveys – one representative of heterosexual Britons, and another representative of Britons who are lesbian, gay, bisexual or other sexualities – shows that straight women are the least likely to always orgasm, at 30%.

While this is closely followed by bisexual women at 32%, lesbian women are more likely to report always orgasming at 40%.

On the flip side to straight women being the least likely, straight men are by far the most likely to climax during sex, with 63% saying they always orgasm. This is slightly lower for gay men at 56%, and bisexual men at 54%.

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As well as this, the data also unearths that some straight men seem oblivious to their partner's lack of orgasms, or, arguably worse, are disinterested.

Fewer than half of straight men (42%) insist their partner usually climaxes every time and a fifth (22%) claimed to witness multiple orgasms, but this appears to be an overestimate, considering only 30% of straight women say they reach climax every time and just 11% say they orgasm more than once.

It appears straight women are more able to accurately predict the pleasure of their partner, with two-thirds (67%) saying the man they're sleeping with orgasms every time, a figure close to the 63% of straight men who report having consistent orgasms.

Among bisexual people, there are similar trends in terms of men being more likely to say they orgasm than they think their partner does, and the opposite with women.

But gay men appear to be more aligned with their partners' enjoyment levels than straight men, with the figure of those who say they orgasm every time coming close to the 63% who say their partner always does.

However, lesbian women are more likely to think their partner is orgasming more than they are – 53% say their partner always orgasms, but only 40% report doing so themselves.

It's worth taking into consideration that it's easier to assess how often male sex partners climax.

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So, while it's also important to remember that some find it easier to climax than others, the big question – why aren't more women reaching climax and what techniques are those who do orgasm using?

Analysing straight women, 38% of those who orgasm at least once every time they have sex say they have clitoral stimulation during their sexual encounters, while just 18% of those who don't always orgasm say the same.

While both groups are more likely to report that vaginal penetration happens every time they have sex, it's a different story among bisexual women. In fact, bi-women who orgasm consistently are less likely to say vaginal penetration is a constant feature in the bedroom.

Many women aren't able to orgasm due to their anatomy, so the fact vaginal penetration happens more often than clitoral stimulation among straight women who always orgasm is likely more down to the fact vaginal penetration is the core component of intercourse, than it is specifically responsible for whether or not a woman orgasms, the YouGov data points out.

The findings are similar in lesbian women, with little difference in how often orgasms occur among those who receive vaginal penetration (16-18%), but far more likelihood of climaxing every time among those who always receive clitoral stimulation (58%) than those who don't (35%). In short: focusing on the clitoris is key to your chances of climaxing.

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Lesbian women who orgasm every time they have sex are also more likely to say they always receive oral sex (27%) than those who don't orgasm every time (8%).

The type of sexual acts people indulge in is clearly a contributing factor to pleasure, with almost two-thirds of lesbian women (65%), and 62% of bisexual women, receiving clitoral stimulation every or most times they have sex, whereas this only applies to half of straight women.

Similarly, lesbian and bisexual women are much more likely to receive oral sex (37% and 35% respectively) every or most times they have intercourse, compared to 20% of straight women.

On top of this, nearly three-quarters of straight women (72%) and bisexual women (75%) say they are on the receiving end of vaginal penetration every or most times they have sex, compared with one in three lesbian women (36%).

Meanwhile, while straight men are overestimating their partners' pleasure, they are also overestimating on their sexual variety. For example, two-thirds (67%) say they always or mostly include clitoral stimulation when having sex with their partner (17 points higher than the number of straight women who report this), and 33% say the same in terms of giving oral sex (13 points higher than straight women report).

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These types of discrepancies among gay men and lesbian women are smaller, where they exist at all. As a side note, the survey also set straight a misconception some may have about sex among gay men, that anal sex is a constant feature. It finds that only 23-24% of gay men say they give or receive anal sex most or all of the times they have sex.

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