With less than two weeks left to sign up for health insurance on Obamacare exchanges, women who are thinking of gambling on not getting coverage this year may want to consider a new study that suggests that coverage could mean more money in their pockets than if they remain uninsured.
Take the case of a 27-year-old woman who buys the least-expensive "bronze" Obamacare plan with an average cost of $1,116 annually. First off, she would not have to pay $115 in out-of-pocket costs for some standard women's health services, including contraceptives and pap smears, the NerdWallet analysis found.
The analysis suggests a woman might come out financially ahead even if she buys a pricier "silver" Obamacare plan, with an average annual cost of $1,740, provided she uses more than the handful of "standard" services that the price-comparison company used as a baseline for annual costs.
(Read more: Obamacare enrollment tops 5 million, two weeks out )
However, if she used only those few services and remained uninsured, that average 27-year-old in a silver plan would spend about $510 per year more on insurance premiums than on the total average of $1,231 in out-of-pocket costs.
But she would also have insurance that would cover a range of additional benefits if she needed them. The analysis assumed this 27-year-old earned $25,000 per year, qualifying her for government subsidies to offset the cost of Obamacare premiums.
Under Obamacare, a slew of preventative services and birth control including oral contraceptives are now covered by law by insurance plans, without any out-of-pocket costs to the insured person.
A recent Phoenix Marketing International survey of more than 3,000 women found that half of them were unaware that all forms of prescribed birth control are free to those with insurance. That's despite the fact that an estimated 99 percent of all women who engage in sexual intercourse between ages 15 and 44 will use some form of birth control.
(Read more: Eleventh-hour Obamacare rule juggling begins )
The NerdWallet cost analysis shows "it makes a tremendous amount of sense" for uninsured women to buy Obamacare coverage, said Christina LaMontagne, the analyst who did the study. "There's definitely a significant financial incentive for women to sign up."
LaMontagne said that incentive strongly contributes the fact that women so far make up 55 percent of the buyers of Affordable Care Act insurance plans sold on one of the government-run Obamacare exchanges.
She said her analysis was "pretty conservative" because it considered only the costs of a year's supply of birth control, a well-woman doctor's visit, a pap smear, an HIV screening and two blood draws.
LaMontagne noted that the study did not consider the potential costs of breast cancer screening or pregnancy. Nor did it factor in the penalty a woman would pay for choosing to remain uninsured, which in 2014 would be equal to $150 for the hypothetical 27-year-old earning $25,000 annually.
The analysis used a one-year supply of the brand Yasmin oral contraceptive, assuming a total cost of $744 per year. LaMontagne said NerdWallet chose that brand, which costs more than generic oral contraceptives, because it is widely prescribed.
Planned Parenthood said out-of-pocket costs for oral contraceptives total about $600 per year on average.
Alina Salganicoff, vice president and director for women's health policy at the nonprofit Kaiser Family Foundation, said the NerdWallet analysis was useful because it lays out how much sense it can make in pure dollars-and-cents terms for women to purchase insurance, particularly with the subsidies available to low- and moderate-income people on the Obamacare exchanges.
But Salganicoff said that even if the math shows that a woman would pay more in premiums than she would in out-of-pocket costs if she remained uninsured, under certain scenarios, it still makes sense for them to buy health coverage.
(Read more: All over the map: States' 'paid' Obamacare rates )
"Insurance is protection," Salganicoff said. "Protection from things that are not average. That's really important to think about ... as we know, things happen in life, people get an illness, they have a catastrophic accident, even something as simple as having a baby can be very expensive."
—By CNBC's Dan Mangan. Follow him on Twitter @_DanMangan.