Births in Masterton over the past decade are down on the previous 10 years, but the stork has steadily increased visits to Carterton and South Wairarapa.
According to Statistics New Zealand, an average of 298 babies were born in Masterton each year over the past decade. During the previous decade an average of 320 babies were born each year.
In Carterton, the average births per year increased from 87 to 96. In South Wairarapa, they increased from 117 to 120.
Wairarapa midwife Birgit Mitchell, who started work last year, said she struggled to get enough clients due to low birth numbers. She had about two clients a month, and would like to have three or four, however she said things would usually pick up from June.
She worked all over Wairarapa - including South Wairarapa, Masterton and Carterton - and said some of the families she worked with commuted between Wairarapa and Wellington, which could make things difficult.
Nationally there were 57,476 births from March last year to March 2015 - the lowest since 2004.
Emeritus professor Ian Pool of the University of Waikato said the decline was due to the increased age of child-bearing women. The most common child-bearing ages are between 25 and 34, and there has also been an increase in women giving birth between the ages of 35 and 44.
Since the mid-1970s, New Zealand's total fertility - or number of births per woman - remained static at two births per woman, but the age of first-time mothers has shifted massively.
While woman had children at older ages in the past, those women often already had children, where as people now were having their first child at an older age, Dr Pool said.
However, Statistics New Zealand analyst Anne Howard didn't think New Zealand's birth figures would continue to drop. She said births per year had been fluctuating at about the 60,000 per year mark, and this was expected to continue.
The large number of women born in the 1960s were past having children, but a relatively large group of women born around 1990 are reaching prime age for having children.
"The picture's a little bit complicated," Ms Howard said
She noted there had been a marked drop in teenagers having children over the past six years, though it was hard to say whether this trend would be permanent.