My doctor recently prescribed me on cerazette which i havent started taking yet as i was due to next week when my perido came. A week after, i am due to go into hospital. I was wondering if it would be okay for me to start them after my operation (a week after i got my period) i know that if it was okay it would take 7 days for them to kick in but it is okay to start them after i got my period?

I think this is better answered by your doctor. I don't think any of us could give you a proper answer.

Nevertheless, If I had to take a guess, I would say it was a bad idea to take it a week after your period. The reason why they have to start either the day of or the Sunday after your period, is to keep your cycle more-or-less on the same schedule. When you start taking the pill at the wrong time, it can lead to a number of strange side effects, such as breakthrough bleeding, spotting, and any other weird things. That's why I personally wouldn't advise it.

I think you should definitely ask your doctor. If he/she says it's ok, then fine, but just know that the potention for weird effects to occur as a result is there, and don't be at all surprised if you experience those weird effects.