Depo Shot Restart: Safety After a Delayed Injection & Abstinence

Question
Hello;
I am a 26 year old married female.  I have been on depo for nearly 3 years.  I was due for my shot at the begining of June.  I was going to go off of depo, so I did not have my shot last month as I normally would have.
I changed my mind and decided it would be best to stay on depo for now.  I had my depot shot today, about 1 month late.  I have abstained from intercorse for the past month (once depo was past 12 weeks).  
I would like to know if the depo is effective again right now or if there is some waiting period.  I have not had a period while on depo, and even durring the month I was late I did not have a period.  So I have no real way of knowing where I was in my cycle.
Thanks

Answer
Dear Karen,

If you were delayed in getting the injection, they definitely should have done a pregnancy test before giving you the Depo injection. If that was negative and you had not had unprotected sex in the 30 days prior to the test, you can be fairly certain you are not pregnant NOW.

As to the effectiveness of the Depo Provera injection - The first shot of Depo Provera is usually given during or a few days after the start of a menstrual period. After 24 hours, the shot is effective birth control for the next 13 weeks. However, if you are more than a week late for your shot, you should use a backup method of birth control for the next two weeks.

I hope this has helped you and answered your question. I wish you well.

Brenda