When can pregnancy be considered a pre-existing condition when attempting to obtain health insurance?

I know certain things and meds your already on are considered pre-existing conditions typically. However, if someone is already pregnant and signs up for their insurance plan at work can they be denied coverage related to the pregnancy? What if the person marries and is added onto the husbands health insurance policy? The only thing I have heard for sure is if you obtain health insurance yourself independently and purchase the maternity rider, then you cannot become pregnant for a specific amount of time after you get it.
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Pre-existing conditions for group coverage from your work will be covered. If you're ever offered group short term disability, take it. It will cover your maternity leave. Just to clarify when you're eligible for enrolling: If you're a new employee, your first open enrollment period is when you've been at your job long enough to qualify for the benefits they offer. That is usually 3 or 6 months. The time period is set by your employer. Generally, they will give you the health insurance information when you become eligible and you can enroll then. Be sure to get your paperwork turned in before the deadline. If you didn't enroll during your new employee enrollment period, you will have to wait until open enrollment that comes once a year. It's common for large companies to have open enrollment in December for a January 1 start date. You'll need to ask your HR department when open enrollment is because it can vary. If your insurance premiums are deducted pre-tax, your employer is obligated to follow the rules above to stay in compliance with IRS regulations. So you need to pay attention to the enrollment periods. Saving tax dollars by pre-taxing means you have to follow IRS rules that say you can't make any changes until open enrollment except under certain conditions like marriage, divorce or having a child. If you get married and want to be added to your spouse's policy, you have 30 days to get that done. You'll also be able to add your new baby to the policy after birth.
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