They jumped from 1.9 per cent in 2013 to 4.4 per cent in 2017 in Hawke's Bay.
The West Coast had a home birth rate of 12.5 per cent in 2011.
Grey said water births had been popular since the late 1990s.
Her advice was to birth in the environment you feel most comfortable in with people you trust and want to have there.
Having low stress will help the labour progress smoothly.
She said the newest birthing trend was encapsulating the placenta.
The placenta is freeze-dried, ground and put into capsules, which the mother takes for the nutrients. It had really picked up in the past five years, particularly within the Asian community.
Christchurch midwife and adviser Jacqui Anderson believed Maori culture had influenced New Zealand women with regard to the handling of the placenta.
Many opted to keep theirs and bury it in a special place.
One of the biggest changes after 1990, when midwifery regained its status as an autonomous profession, was continuity of care. Instead of sometimes seeing more than 50 healthcare professionals during her pregnancy, a woman was assigned one midwife
"In the last 20 years, women have become more comfortable in being able to identify what they want and expect," says Anderson.
"[For midwives] it's much more about walking alongside the woman and her family as opposed to saying, 'You're pregnant and these are the things you have to do'."
Anderson, who estimated she had seen up to 2000 births in her 34-year career, said support for women who chose to home birth had increased dramatically.
Two or three decades ago, women were chided when they had to go into hospital after trying to give birth at home.
"Now it's, 'Okay, you need some extra help and here we are'.
It's about a birth being a much more personalised experience rather than something just done to a woman. You're not just a number."
In the past 10-15 years, hospitals had incorporated more friendly tools, such as birthing rooms, pools and birthing stools.
Using a birthing pool to provide pain relief during labour and birth was common.
Anderson said there were benefits, backed up by evidence, that having a natural birth with minimal intervention was best for mother and child.
However, for some at-risk mums, a caesarean outweighed a vaginal birth.
"Women are quite hard on themselves ... In the end the best outcome is a healthy mum and healthy baby," says Anderson.
New Zealand's record low fertility rate shows women might also have more control on getting pregnant.
Data from Statistics New Zealand showed our national fertility rate was down to 1.81 births per woman — the lowest level since records started in the 1920s.
The lower fertility rate could lead to reduced population growth if it stayed below the replacement level of about 2.1.
