Take a look at the conditions required:
1) According to the IRDA you can port the policy only at the juncture of renewal. That is, the new insurance period will be with the new insurance company.
2) Apart from the waiting period credit, all other terms of the new policy including the premium are at the discretion of the new insurance company.
3) At least 45 days before your renewal is due you have to
a) Write to your old insurance company requesting a shift
b) Specify company to which you want to shift the policy
c) Renew your policy without a break (there is a 30 day grace period if porting is under process)
IRDA has created a web-based facility to get and maintain data about all health insurance policies issued by insurance companies to individuals so that it can be accessed by the new company to which a policyholder wishes to port his policy.
This enables the new insurer to obtain data on history of health insurance of the policyholder wishing to port his policy.