If you qualify for FMLA leave, yes — your company must continue to keep you on its health insurance plan while you’re on leave. But the company has the legal right to ask for the reimbursement of your health insurance premium payments if you do not return after your FMLA leave.
Also, keep in mind that FMLA doesn’t require employers to allow you to accrue benefits or time toward seniority when you’re out on leave. That means the clock may stop on things like vacation accrual and the amount of time you can say you’ve been with the company in order to qualify for things like raises based on seniority, participation in your company’s 401k plan or the vesting of your company’s matching investment, or stock options.
Finally, you won’t be able to contribute to your 401k or flexible spending account while you’re on leave because you’re not receiving a paycheck from your employer — which means you can’t contribute pre-tax dollars.
Most companies that offer fully-paid maternity leave (not through STD policies) also pay to cover your other employment benefits during this period.