A team of British and Norwegian researchers have suggested that women whose elder sisters had children in their teenage were more likely to do the same as compared to other women. To conclude the findings, they analyzed thousands of women and their families over decades.

While explaining the study, Is Teenage Motherhood Contagious?, the co-author of the study, Professor Carol Propper, from the University of Bristol's, said there are a number of evidences to show that family environment and education are key factors to affect the rates of teenage pregnancy.

"However, these findings reveal the positive sibling effect (on conception rates) still dwarfs the negative effect of education. These findings provide strong evidence that the contagious effect of teen motherhood in siblings is larger than the general effect of being better educated”, added Professor Carol Propper. "This suggests that more policies aimed directly at decreasing teenage pregnancy may be needed in order to reduce teen births”.

In addition, experts have notified that they deeply analyzed the sister-to-sister relationships as sisters spend more time together and therefore get influenced by each other’s behavior. Further, the sibling effect was observed more among women from poor background.