Unfortunately for the mothers of teenage children, bed time routines no longer revolve around a bath and a story, but often feature a battle over the use of handheld devices and an argument regarding the time spent on social media,

However, if your children's protests have started to cast doubt on the concern you feel regarding their use of social media, a recent study may remind you that your worries have considerable merit.

According to research from University College London, experts in the field have determined that teenagers who use social media websites 30 minutes before sleeping do not perform as well in school as their counterparts who don't.

Scientists, who explored the impact social media usage and lack of sleep has on a child's academic ability, ascertained that 70% of 16-19-year-olds who used social media before bed achieved 20% worse grades than fellow pupils who removed the phone from their night time routine.

With teenagers requiring approximately 10 hours of sleep in order to function properly, the use of handheld devices and a reliance on social media tends to disrupt this requirement resulting in poor academic performance.

Elaborating on this issue, the study's lead author, Dr. Dagmara Dimitriou, insisted: "Sleep is essential for processes such as memory consolidation and academic performance."

Using 48 pupils from an independent sixth form college in London, researchers established that our teens are only averaging seven hours of sleep a night - a discovery which raises concern among experts who insist sufficient sleep is vital for optimal brain development.

Suggesting a reason for the considerable lack of sleep, researchers surmised that "the introduction of television sets, games consoles, mobile phones, laptops and tablets into the bedroom" play a role.

Concluding their findings, researchers explained: "As adolescents have greater access to technology use in their bedrooms, several studies have noted the link between this modern day phenomenon and the reducing hours of sleep."

The study has been published in Frontiers in Psychology.