People will always have certain "types" when it comes to choosing partners and this also extends to a woman's choice of sperm donor, researchers from the Queensland University of Technology have found.

In a study published in the journal Applied Economic Letters, the researchers showed that women choosing sperm donors on the internet have a preference for intellectual, methodical, calm and shy candidates, resulting in more children being produced by non-extroverted men. Called "Determinants of online sperm donor success: how women chose," the study was carried out by Benno Torgler and Stephen Whyte from the QUT Queensland Behavioral Economics Group.

According to Whyte, demand for sperm donors has risen throughout the world to the point that an informal online market has sprung, allowing children to be born outside of the more formal setting of a fertility clinic. Sperm donors do have to promote or sell themselves to women so it was easy to assume that the task will be a walk in the park for extroverted men. However, as the study showed, extroverted men are actually not at the top of the pack.

At the other end of the spectrum, men who are socially awkward or fretful are also less likely to be chosen by women looking for sperm donors.

Researchers believe that this study was to the first to involve males donating sperm completely through unregulated forums and websites. It included interviews and data gathered from 2012 to 2013. With ages between 23 and 66, the 56 men in the study hailed from the U.S. Canada, Australia, Sweden, the U.K. and Italy. Because the online donor market follows a different dynamic compared to what fertility clinics have, it promotes interaction between the sperm donor and a recipient.

"This allows us to explore individual donor personality characteristics and how likely they are to be chosen by women as their donor," added Whyte.

The results of the study supports findings from previous research noting that humans are good at assessing personality traits and intelligence levels even with minimal exposure to behavior and appearance. Additionally, the results also showed that 73 percent of participants in the study have kept in touch with at least one of the children they produced via email, phone, video chats and even in person.

Photo: Kyle Adams | Flickr