(WASHINGTON) -- Wednesday is a big day for birth control. Under President Obama's health care reform, private insurance companies have to start providing contraception for free on Aug. 1. That means no more co-pays for birth control.
But while the law goes into effect, only a tiny fraction of the 97 million American women between the ages of 18 and 64 will be able to snag any co-pay free contraception.
First, only women with private insurance plans will be affected. About 65 percent of women between the ages of 18 and 64 -- those that are old enough to be adults but too young enough to qualify for Medicare -- have private health insurance, which they get from their employer or pay for out of pocket, according to the Kaiser Family Foundation.
That means the 19 million women between the ages of 18 and 64 who are uninsured will still have to pay for contraception out of pocket.
The 17 million women on Medicaid also may not feel the effects. Each state gets to decide whether their Medicaid plans will provide at no cost the contraception and seven other women's health services that are covered under the no-cost-sharing law taking effect on Wednesday.
While the federal government provides cost incentives for states that drop contraception co-pays for Medicaid enrollees, states are not required to. Some Medicaid programs already provide these services for free.
Even for the 57 million women that have private health insurance, if their plan has not changed since the Affordable Care Act was enacted in March 2010, it can be grandfathered in and does not have to adhere to the co-pay free rules.
The administration estimates that by 2013 about half of large employer insurance plans and about one-third of small employer plans will still fall under this grandfather clause and therefore not be required to provide free contraception.
Women whose plans have changed may not see their co-pay free benefits go into effect for almost a year, depending on when their most recent plan started. The law stipulates that any plan starting on or after Aug. 1 has to offer birth control along with seven other women's health services for free.
So if your plan started on July 1, you may have to pay co-pays for nearly a year until your new plan begins on July 1, 2013, although some insurances plans have said they will implement the law early.
Women who get their insurance through their religiously-affiliated employer will have to keep paying those contraception co-pays for the next year as well.
The Obama administration gave religiously-affiliated employers, such as some universities and hospitals, a one-year exemption to the free birth control requirement after many raised religious objections to paying for something they consider a sin.
Those religious organizations still have to provide insurance that offers the seven other services cited in the women's health rule taking effect on Wednesday at no cost to employees. Those co-pay free services include: a yearly well-woman doctors visit, HPV testing, gestational diabetes testing for pregnant women, counseling for sexually transmitted diseases, HIV screening and counseling, breast pumps and domestic violence counseling.
Copyright 2012 ABC News Radio