Health insurance is a formal agreement to provide and/or pay for medical care. The health insurance policy describes what medical services are "covered" by the insurance company. There are medical services that are not "covered" and will not be paid by your insurance company.
There are a variety of private and public health insurance programs. Most women obtain health insurance through their employer or as a "dependent" in a family plan. There also are public health insurance plans funded by the federal and state governments.
This information is based on source information from the National Women's Health Information Center.