"When it comes to a woman's right to make her own health care choices, they want to take us back to the policies more suited to the 1950s than the 21st century," Obama said at a campaign speech in Colorado.
Obama is on a two-day visit to Colorado, which is considered to be a key swing State in the November presidential elections.
"You've got to make sure it does not happen. The decisions that affect a woman's health, they're not up to politicians, they're not up to insurance companies," he said.
Romney, he said, is running as the candidate of conservative values.
"There's nothing conservative about a government that prevents a woman from making her own health care decisions," he said.
"He says he's the candidate of freedom. But freedom is the chance, the opportunity to determine for yourself the care that you need, when you need it. It's the ability to change jobs or start your own business without fear of losing your health insurance," Obama said in another criticism of his Republican rival.
"We're not going back to the days when it was acceptable to charge women more than men for health care. We are not going back to the days when women with preexisting conditions, like being a cancer survivor, were denied affordable care.
We're not going to kick more than a million young women off their parent's plan. We are not going backwards, Denver. We're moving forward. That's why I'm running for President again," he said amidst a round of applause.
"When my opponent's campaign was asked if he'd fight to guarantee an equal day's pay for an equal day