Employee joined on Jan -18, if she conceives in Mar '18 - Can she claim the hospital expenses through group health policy?

Dear team, If an female employee joined on Jan -18, if she conceives in Mar '18 And her expected date of delivery is Ex;-10-oct-18
My Doubt is she is not under ESI & Suppose we have taken Group health policy in sep-18 or Dec -18 can she claim the hospital expenses through group health policy ? Please suggest

Most of the general 'health/Mediclaim policies' under group insurance doesn't cover pregnancy/delivery authomatically. There should be special coverage by paying extra premium to cover these hospitalisation expenses. And how you can raise a query for an event of Sept.2018-Dec.2018. No chance at all now.
However if this female employee was not covered under ESI, having served Jan'18 to Mar'18 (minimum of 80 days) she could have been covered under the Maternity Benefits Act. Pl. check this aspect, I'm not sure.