What if recently recieved health insurance and were pregnant but didnt know? Coverage void?

My question is what if you recoently purchased health insurance and you were only a few weeks pregnant and found out after the fact. Will the health insurance company void coverage on maternity care?
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That's why there are waiting periods for maternity riders. Normally, when you purchase a private maternity policy in the US, it won't actually cover any maternity expenses for a specified waiting period (usually 10 months to a year). This is to prevent any possibility of covering a pregnancy that existed when the policy was purchased. So, the health insurance portion of your policy should still be valid. But you wouldn't have coverage for maternity expenses. You should review your policy and/or contact your insurance company to confirm what the waiting period on your policy is.
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