About 65% of babies born in Dunedin Hospital last year were of an optimal birth weight, defined as between 3kg and 4kg, Ministry of Health data reveals.
Of the 1701 babies born in Dunedin Hospital last year, 1097 weighed between 3kg and 3.999kg.
After a 42-hour labour, Bridget Dawson (29) gave birth to a 3.74kg (8lb 4oz) baby girl in the Queen Mary Maternity Centre in Dunedin Hospital on May 20.
The 51cm baby – Alyth Wentworth – was in the centre when The Star visited the day after her delivery.
Miss Dawson, of Cromwell, said she had expected a big baby because her partner, beekeeper Justin Wentworth (27), was 5.95kg when he was born and was now about 2m tall.
Dunedin School of Medicine dean Prof Barry Taylor said parents being overweight had more of an effect on the size of a baby than the amount of bone and muscle the parents had.
The optimal size for babies was between 3kg and 4kg, he said.
The latest ministry data on birth weights in New Zealand is for the 2016 year.
A comparison of the national data with Dunedin Hospital data for 2016 reveals a greater percentage of babies born in Dunedin Hospital were lighter than 2kg than across New Zealand.
Pregnant women with small babies “not growing well in the womb” in the Dunedin Hospital catchment were referred to Dunedin Hospital for the delivery of their baby, Prof Taylor said.
Consequently, the percentage of smaller babies born in Dunedin Hospital was greater than the national average, he said.
The ministry data also reveals Dunedin Hospital had a smaller percentage of babies weighing more than 4.5kg than the national average in 2016.
Prof Taylor said he believed fewer babies weighing more than 4.5kg were being born in Dunedin Hospital because it dealt with smaller numbers of certain ethnic groups than other hospitals in New Zealand.
Parents in some ethnic groups were bigger because of genetics and being overweight, and consequently, had bigger babies.
About 60% of Pacific Island women giving birth in South Auckland were obese, he said.
“It has an effect on the birth weight of the baby.”
It was important for women to eat a healthy diet with limited sugar intake and lots of vegetables both before conception and during pregnancy to ensure a healthy birth weight for their newborn.