Women on a benefit who take up the Government's offer for free long-acting contraception will also be able to have their contraceptive device removed for free for either medical reasons or if they later decide against it.
The Government's announcement met with a strong reaction yesterday - ranging from calls to make it universal to claims the Government was "coercing" women into contraception to avoid losing their benefit.
Social Development Minister Paula Bennett said yesterday that it was voluntary and case managers would not be pushing women to take up the option.
Last night her office also confirmed the grants could also be used to remove a contraceptive device later, whether out of personal choice or because of medical reasons.
The initiative drew fire from National's ally - Maori Party co-leader Tariana Turia, who is also the associate social development minister. She said it was insulting to tell somebody how many children they should have.
"I've always supported the growing of our population, the growing of our hapu and iwi and so I'm certainly not one who's ever believed that we should be controlling people's fertility."
Labour leader David Shearer said it should be extended to all women in need of contraception rather than just beneficiaries.
And Green Party co-leader Metiria Turei said it would coerce women into taking up the offer out of fear they would otherwise lose their benefits.
"The Government has no right to intrude on a woman's choice to have a child. It should get its hands off our wombs."
Ms Bennett and Prime Minister John Key both defended the policy, which Mr Key said was "pragmatic and common sense". Ms Bennett said she would consider it insulting not to offer it, because that took away the choice for women who could not otherwise afford it.
While the idea of extending free contraceptive devices to all women had merit, her immediate focus was on those on benefits.
Mr Shearer also questioned why the responsibility was being put on women rather than men to get contraception.
Ms Bennett said Work and Income already paid for vasectomies for men when requested, and had done so since 1992. However, there were no other long-term options for men - and others, such as condoms, were already free.
She said she did not have a personal view on sterilisation, as it was a personal choice. Work and Income had funded permanent options such as vasectomies and tubal ligations, but they were dealt with on a case by case basis.