Under a federal law known as HIPAA, health insurance providers cannot consider pregnancy a pre-existing condition, so you should be able to take out insurance, and file pregnancy-related claims, even after you're already pregnant. However, there are some exceptions: if you have never had health insurance, your new provider may classify your pregnancy as a pre-existing condition; some companies have a one-month waiting period. HIPAA only applies to group health plans, not individual plans. However, there are companies designed specifically for maternity insurance that you can use if you are not eligible anywhere else.