Mum at loss to explain weight gain

Courtney Tauranga gained 46kg while she was pregnant with her fifth child, son Michael Punga, who is now three weeks old. Photo / Greg Bowker

Courtney Tauranga has put on a "huge" amount of weight when pregnant with each of her five children, but soon gets back to her usual size.

"I'm normally 70 to 75kg when I'm not pregnant," said the 32-year-old stay-at-home, breastfeeding mum, who lives in Manurewa with her partner and children.

"When I'm pregnant I have been up to 136kg. I don't change the way I eat - I eat normally. I just get really, really huge. No one knows why I put on so much weight.

"I'm physically fit - I coach rugby league and I do a triathlon at the end of every year. I take pride in my appearance," she added.

"The baby I just had - Michael - he was 8 pounds 6 ounces [3.8kg] and I was 116kg. Before getting pregnant, I was 70. He's 3 weeks old and I'm down to 92kg.

"I was diagnosed with gestational [pregnancy-related] diabetes. It was the first time I have been diagnosed. I had to cut down on bread. I don't overindulge in food," said Ms Tauranga.

Her usual, non-pregnant weight is technically overweight, but she says she doesn't consider herself overweight "because most of it turns into muscle after a while".

Having had a bout of gestational diabetes, she is at increased risk of developing type 2 diabetes and believes the disease is "in my genes".

Two of her siblings have diabetes and her father died of kidney failure related to diabetes.

Ms Tauranga said all her babies had been born big. The largest was 4.99kg and the day he was born she was 136kg. He had remained big, but was not fat.