The 18 companies and numerous other religious and quasi-religious institutions that have filed lawsuits challenging the birth control mandate of the Affordable Care Act are challenging it on First Amendment freedom of religion grounds. Some have argued that this mandate protects women's rights by taking the choice away from employers and forcing upon them the will of the majority for the "common good."
Their argument goes that by not allowing private companies operating in the public sector to decide what type of insurance they are willing to purchase for their employees, we would be advancing democracy and upholding the separation of church and state. Of course, privately owned corporations are neither church nor state, so these arguments must fail. The argument that this advances democracy must also fail, as it is unconstitutional and completely ignores the entire premise of the Bill of Rights, which is to protect individual liberties from arbitrary whims of the majority.
Some point to the fact that 70% of Americans want birth control to be free and covered by employers as evidence that we should accept this desire as being for the "common good." What they overlook is the fact that there is no such thing as a free lunch. The extra cost of providing birth control will be borne by all of us in the form of higher taxes, higher insurance premiums, higher unemployment, and cost of moral hazard. Moral hazard could manifest itself financially when more women use expensive hormonal birth control rather than other methods of prophylaxis; we could also see detrimental health effects in the form of STIs if there is a large shift from condoms to birth control pills.
Advocates of mandating birth control coverage do make one correct assertion though: eliminating full coverage of birth control would disproportionately effect women of lower socio-economic status. By eliminating this mandate, more jobs would become available to those women if employers were not forced to consider limiting the size of their staff or the number of hours an employee could work based on the Obamacare mandate.
Rather than seeking to impose financial and moral costs on employers for the sake of the "common good," it would better serve advocates to push for the deregulation of birth control pills and to have them made available over the counter, which would create a competitive market and drive prices down to the same levels of other (potentially more dangerous) over the counter drugs, such as aspirin. In this way we could achieve the result of increased access to birth control for women, without the unintended economic or legal consequences.