Being well-endowed may have many upsides, however researchers have found it has one major drawback – that your wife is more likely to cheat.

A study published in the journal PLOS One has found that men with larger penises are more likely to be cuckolded by their wives.

Led by researchers from the US and Kenya, the researchers looked at extra-marital affairs of women married to fishermen living along Lake Victoria in Kisumu County, Kenya.

Findings showed that women were more likely to cheat on husbands who had longer penises, and that size correlated to cheating risk.

The authors had been looking at predictors for extra-marital affairs and found several factors caused them, including when a husband had a "longer erect penis".

"Domestic violence, denial of a preferred sex positions, longer erect penis, younger age and increased sexual satisfaction were the main predictors of women's involvement in extra-marital partnerships," they wrote.

"Surprisingly, [having a] spouse [with a] longer fully erect penis was associated with increased likelihood of the women having extra-marital partnerships. From these results, every one inch longer penis increased the likelihood of women being involved in extra-marital partnership by almost one-and-half times.

"Similarly, our qualitative data also support this finding. Women associated large penises with pain and discomfort during sex which precludes the enjoyment and sexual satisfaction that women are supposed to feel."

Research shows that the longer the penis, the more sexual discomfort women suffered during sex. Some women interviewed said that painful sex had led them to seek sex elsewhere so they could enjoy it.

Concluding, the authors say men need to understand that a larger penis does not necessarily make them better lovers and should not seek out penile enhancement procedures to enhance their genitals.

"If results from this study are anything to go by, it may be counterproductive for men to seek penile augmentation while their sexual partners are running away from the same and seeking sexual satisfaction elsewhere."