"Why should, say, a 70-year-old who's had one partner all their life be paying for a young woman to sleep around?
"We are the country with the most promiscuous young women in the world. This does nothing to help us at all."
Mr Craig said international research showed young Kiwi women are sleeping around and living what he called a "destructive lifestyle".
"We are faced with a reality that the constant changing of partners is a decision young women are making. It's a destructive decision on a lot of levels. Health is one of those, and it is a big cost to us."
However Mr Key has said today he hasn't seen anything to back up Mr Craig's claim.
He told reporters in Porirua this morning that providing longterm contraception was a logical thing for the Government to do ''which is to provide support to young vulnerable women, give them a voluntary option, to employ a doctor to give them advice and support in that area."
Asked if he could work with someone like Mr Craig, Mr Key said he was not going to critique every statement of someone who wasn't even in Parliament.
"At the end of the day we work with lots of partners and we don't always agree with everything they say and they don't always agree with us.
"It doesn't mean that we cant work constructively so I'm not in the process of ruling them out but I just hasten to add we are two and a half years away from an election and I wouldn't worry about it too much."
Maori co-leader Tariana Turia said it was outrageous for anyone to talk about promiscuity of New Zealand women when they probably knew nothing about anywhere else in the world.
"We do try to operate on evidence and we don't lie in the bedrooms of other people."
Minister of Education Hekia Parata said she didn't agree with Mr Craig's comments.
"That hasn't been my experience.''
She said she was an aunt, a mother and a cousin and hadn't found women to be more promiscuous in New Zealand.
Winston Peters also dismissed the comments.
"I am not worried about Colin Craig and his conservative party. Everybody knows that they trawled through our manifesto last election, stole most of it and can't defend it,'' he said.
"It just demonstrates how desperate that National party is.''