Six women who work in the 16-strong mortgage collection team at the building society's Moulton Park office fell pregnant within five months of each other, with Samuel, the youngest Nationwide baby, born four weeks ago.

From August of last year the members of the team – who have had 14 children between them – were announcing their pregnancies on an almost monthly basis.

Two of the friends – Alison Buttress, aged 29 and 28-year-old Michelle Nock – even broke the news to the office on the same day.

Tina Matty, whose daughter Georgia Emily is now six months old, was the first to tell her colleagues she was expecting, followed by Alison, mum to 19-week-old Libbie, and Michelle, mum to five-month-old Teagan.

Stacey Bulmer, aged 28, who now has a 16-week-old daughter Emily, was next to make the announcement.

Tina, aged 37, said: "By the point Stacey told us she was pregnant we were starting to think about who would be next. "

Katie Rake, mum to Samuel, was next to tell her colleagues about her pregnancy with 37-year-old Sarah Robinson, now mum to 10-week-old Zachary, sharing the news of her impending arrival at the beginning of the year.

Katie, age 25, said: "When our bosses found out they were gobsmacked!

They've joked about putting the Pill into the water."

All six women took the jobs at Nationwide because of the flexible hours, which allowed those with children to spend time with them during the day.

Members of the mortgage collection team even started swotting up on first aid as the women's due dates grew nearer.

Alison said: "They really wanted someone to go into labour!"

The women will return to work at Nationwide next year.

A spokesman for the building society said: "We wish them all well and hope to be able to welcome them back to the team in the future."