Slightly more contentious, are the precise reasons for these intergenerational shifts.Responses to the ONS statistics released on teen pregnancy this morning point towards social media as a leading cause. Pregnancy rates rapidly began to fall around the same time as Facebook became public, suggesting that teenagers are having less sex because they spend more time online.Economic instability could also be a factor in women choosing to have children later, dedicating more time to their careers. The Telegraph reported last year that the number of middle-aged mums has overtaken the number of young mums in the UK, throwing into question what "middle-aged" even means any more.And what else? Well, while the government would probably like to claim improved sex education as the reason teens are waiting to have kids, they'd struggle to claim better access to contraception. Budgets assigned to sexual health services have been dramatically cut in recent years.Dr Chris Wilkinson, President of sexual health service the FPA comments: "Reduced access to SRH services is likely to burden substantial costs on health and wider public services through large numbers of unintended pregnancies." In other words, if sexual health centres keep closing, rates of teenage pregnancy could stop falling in the near future.