HCF private health insurance cover

I have signed up to the My Fam Silv hospital cover. I have recently fallen pregnant but my due date is within the 12 month waiting period.

Will I be able to backdate my cover by 2 weeks?

If not, what exactly does the private health give you? Will I be at disadvantage or out of pocket a lot?

Does private health cover any obstetrician fees? What vicinity are the obstetrician fees likely to be in?

Thanks