New details emerge about Beyonce's newborn twins' health condition.

Earlier this week, it emerged that a ‘minor issue’ has been keeping Beyonce and her newborn babies in hospital for a week since the birth.

Now, a new report has revealed exactly what’s been keeping them there.

TMZ reports Beyonce’s twin son and daughter were born prematurely and remain “under the lights” for treatment of jaundice, according to sources close to the family.

The ‘lights’ refer to ‘bili lights’, which act as a form of phototherapy involving shining blue fluorescent light onto bare skin at a specific wavelength.

Listen: Midwife Cath talks Hello Bump through what to expect in the first six weeks after meeting your baby (post continues after audio…)

Jaundice is a condition common to premature babies caused by an excess of bilirubin, created when the body replaces old red blood cells with new ones.

This build up manifests as a yellow colouring of the skin and eyes, and although dangerous if left untreated, is usually treatable.

Breaking the golden social media rule of baby announcements, Beyonce’s dad, Mathew Knowles was the first to confirm the arrival of his grandchildren on Twitter.

The parents themselves are yet to confirm the names of the babies.

We’re sending our very best to mum, dad and bubs.

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