"The hospital seems busier, and the birth centre."
She suggested this could be due to a decrease in the number of midwives and fewer resources.
Deaths were also down in the region, by 4.5 per cent between 2015 and 2016. There were 114 fewer deaths last year than in 2015.
There were 1600 more births than deaths in the Bay of Plenty, although the population rose by an estimated 6400.
Immigration into the country has reached a record high, with 5370 people from other countries permanently settling in the Bay of Plenty region alone.
The net gain in migration for the whole of New Zealand - the number of immigrants minus the number of people leaving - was 71,300 in the year to March 2017.
Mr Dolan said there were fewer departures, but this was not the primary reason for the rise.
"This was mainly due to the rising number of migrant arrivals to New Zealand."
Births to teen mothers, in particular, decreased last year, at least at a national level.
In 2016, there were 16 births per 1000 women aged between 15 and 19 in New Zealand, and 33 in 2008.
The teen pregnancy rate peaked in 1972 at 69 births per 1000 women aged 15-19.
"The teen birth rate has also fallen across the Tasman, but Australia's rate remains lower than New Zealand's," Statistics New Zealand spokesman Peter Dolan said.
Family Planning chief executive Jackie Edmond said increased access to contraception was likely part of the reason for the decline in teen pregnancy.
"It's probably a mixture of things. There's no definitive evidence of what it is," she said.
The most common age group for new mothers last year was 30-34.
There were also fewer deaths and fewer births at a national level than in 2015.
New Zealand registered just over 59,000 live births in 2016, and 31,000 deaths.
The fertility rate dropped to 1.87 births per woman. The annual average between 1980 and 2015 was 2.02, Statistics New Zealand said.
There were more births than deaths in every region in 2016.