A 48-year-old Melbourne woman, who already has 10 children, is due to give birth to quintuplets.
There will be a team of more than 30 medical staff on hand when the woman, who wants to remain anonymous, gives birth to the five babies at Clayton’s Monash Medical Centre in the next few weeks.
Little is known about the women, but it's believed she fell pregnant without IVF or the use of fertility drugs – the chances of which are about one in 60 million.
Fertility naturally declines with age, and Melbourne obstetrician Dr Len Kliman told Seven News that to even have a multiple pregnancy after the age of 45 is “particularly uncommon”.
Australia's first recorded case of quintuplets was in 1967, and the Australian Multiple Births Association believes there are only 11 sets of quins in the country.
In 2011, Brisbane couple Melissa Keevers and Rosemary Nolan became parents to Noah, Charlie, Eireann, Evie and Abby.
The babies were born more than 13 weeks' premature at 26 weeks and four days, at an average weight of 869g each.
The quins all survived and are now living in Queensland.
A spokesperson from Monash Medical Centre confirmed that a multiple birth was scheduled at the hospital in the next few weeks but declined further comment.