"It is very concerning for us. One of our goals is to have babies still being breastfed at six months. The benefits of breastfeeding are clearly documented," Dr Benn said.
She said the WDHB had excellent rates of women breastfeeding their babies when they left hospital - around 95 per cent.
"But when a woman has had a baby in hospital, she will usually only stay there for a day or two. Then she has to face the reality of perhaps having to go back to work or school and trying to feed her baby.
"Or maybe she is having problems breastfeeding and it's just easier for her to stop."
Dr Benn said it was likely many women did not know there was a lactation consultant at Wanganui Hospital who could assist with any breastfeeding problems mothers had.
"The support is there, but it seems the message is not getting through."
Dr Benn said she had been talking to midwifery staff at the Gisborne-based Tairawhiti District Health Board.
In that region 37 per cent of 6-month old babies are being breastfed, both Maori and the general population - the best rate in the country.
Dr Benn said Tairawhiti has a number of initiatives for assisting breastfeeding women, particularly young women who are breastfeeding for the first time. These include a programme called Aroha Mama, which sees young mums matched with a "breastfeeding buddy", a mother of a similar age who can provide peer support for her.
"That seems to work very well, and I would say that peer to peer support is so important. There is also a strong La Leche League in Gisborne."
Wanganui does not have a buddy system, and there is no active La Leche League in Wanganui, although there is one in Marton.
The La Leche League is a non-profit organisation that actively promotes breastfeeding.
Whanganui District Health Board's director of Maori health, Gilbert Taurua, said a community-based approach was necessary to turn Wanganui's poor figures around.
"This is not just a DHB problem. There's this societal expectation that young mums will just go back to work, and of course that makes it harder for them to breastfeed. Babies may also spend a lot of time with extended family and again, that makes it harder."
Mr Taurua said plenty of community support was needed, as well as comprehensive antenatal care for mothers.
He said although Wanganui's breastfeeding rates were concerning, it was valuable to be able to compare them to those of other districts in the central region.