http://www.dailymail.co.uk/sciencetech/article-2069018/Teenage-sex-affects-mood-brain-development-reproductive-tissues-later-life.html
This article I found tries to show a link between early sexual activity and bad mood later on in life. To study and prove this correlation the researchers used hamsters as a replacement of humans. The problem with this experiment is that hamsters and humans have vastly different brain chemistry and humans are much more emotionally intelligent. Now besides this huge issue, we can also see that the correlation found (that when the younger hamsters had sex vs. the older, the young were more likely to act “depressed” or “anxious later on in life.”) does not imply causation.
While the researchers did observe a change in the younger hamsters behavior, there was no information on whether or not a control group was used to see if young hamsters without sexual activity were also anxious. Another factor playing into these hamsters moods and actions is simply age. The experiment followed a group of 40 day old hamsters and a group of 80 day old hamsters, therefore the 80 day old hamsters were always older. What should be considered is maybe younger hamsters are generally just more anxious than older hamsters, and activities such as swimming or running through a maze make younger hamsters act differently than any older hamster would, regardless of previous sexual activity.
Making this link with the hamsters and then also implying that “teenage sex leads to bad moods later in life” for humans is not only presumptuous but it is also bad experimenting. If a study wanted to prove this they should attempt to study humans or use an animal with a higher intelligence.
