When you are with a girl for a long time and you know every corner of her in details, she does not make you get off as hard as she used to. You are still having the best time of your life, but when you spot a hot lass or just a super sexy porn video, your juices start flowing more vigorously. It happened to all of us so no need to hide and say it never happened to you. If another girl makes you epically horny, that does not mean you lack in feelings to your partner, we men just are that way*. A study was made at The College of Wooster, showing increase in men’s ejaculation and a higher quality sperm when jerking off to a new babe. However, the study is not aiming to prove that men are built so they can cheat their girls/wives. Furthermore, the study has nothing to do with monogamy, study’s co-author, Dr. Laura K. Sirot said.
It was a 15 days long study where 21 men participated by watching seven porn videos from the “Intimate Passion” series. First six XXX movies featured same actor and actress while the seventh featured different actress. Before each masturbation session participants needed to abstain from alcohol and sexual activity for 48 hours. With other words, they needed to be alcohol and sex free for 15 days straight. After each session they collected sperm to further investigate ejaculation and sperm quality. Study showed that ejaculated volume increased and ejaculated time decreased while semen became, surprisingly, of better quality after watching seventh video featuring different pornstar.
Not only did this (mini) study provide new insights into evolutionary biology, it may also contribute to a better awareness and treatment of male infertility.
A study, published in 2015 June issue of Evolutionary Psychological Science journal, as small as this one may not prove anything right. Way more men should participate in the study to get a proper answer. On the other hand, it may be a start off a new approach to better understand (analyze) male infertility and of course male masturbation.
Men, do not use this study as an excuse for cheating. Instead, use it as your own personal research. With porn, of course! Learn about the power of your ejaculation and the amount of your sperm when switching between pornstars.

*Who said women are any different?