This evening after I flushed the toilet I heard a couple of gurgle sounds then noticed water on the bathroom floor. I tried flushing the toilet again and the water came to the top without going down. There was also sewage at the bottom of the bathtub. I was also doing laundry at the time and turned the washing machine off. I called a plumber. A couple of hours later, still waiting on the plumber, I attempted to flush the toilet again. It flushed without incident. I flushed a couple more times, no problem. I cleaned the shower and canceled the plumber, thinking whatever the blockage was, it worked itself out. I turned the washing machine back on... within 5 - 10 minutes I heard the gurgling sound again, water again on the floor and sewage back in the shower. We have city water. My house is 30 years old; we've lived here for 3 without any plumbing issues. I only have issues in the bathroom. The bathroom sink is not leaking or backing up. There is no water around the washing machine. There is no backup in the kitchen.

Thanks for your assistance.
Follow up: Last night I decided to take a shower thinking everything was fine. After about 5 min the bathtub began filling up with water (mayber an inch at the most). I got out of the shower and let the water drain (it drained, but slowly). While the bathtub was draining, I flushed the toilet to see what would happen. I heard noise coming from the shower (which I never heard before only the toilet made noise). Water filled to the top of the toilet, but did not overflow. There was a small of amount of backup in the shower. The washing machine was not running during any of this. I'm calling a plumber this morning. To Kayakinggirl, we don't have a basement. I don't know if this makes a difference or not, but thanks for responding. Good luck on your situation!

We're having the same problem-the main trap in the basement from the plumbing trunk line is lower than the pipe to the sewer line and that is what is causing the backup in our house. My husband is raising the trap.

This evening after I flushed the toilet I heard a couple of gurgle sounds then noticed water on the bathroom floor. I tried flushing the toilet again and the water came to the top without going down. There was also sewage at the bottom of the bathtub. I was also doing laundry at the time and turned the washing machine off. I called a plumber. A couple of hours later, still waiting on the plumber, I attempted to flush the toilet again. It flushed without incident. I flushed a couple more times, no problem. I cleaned the shower and canceled the plumber, thinking whatever the blockage was, it worked itself out. I turned the washing machine back on...within 5 - 10 minutes I heard the gurgling sound again, water again on the floor and sewage back in the shower. We have city water. My house is 30 years old; we've lived here for 3 without any plumbing issues. I only have issues in the bathroom. The bathroom sink is not leaking or backing up. There is no water around the washing machine. There is no backup in the kitchen.

Thanks for your assistance.
Follow up: Last night I decided to take a shower thinking everything was fine. After about 5 min the bathtub began filling up with water (mayber an inch at the most). I got out of the shower and let the water drain (it drained, but slowly). While the bathtub was draining, I flushed the toilet to see what would happen. I heard noise coming from the shower (which I never heard before only the toilet made noise). Water filled to the top of the toilet, but did not overflow. There was a small of amount of backup in the shower. The washing machine was not running during any of this. I'm calling a plumber this morning. To Kayakinggirl, we don't have a basement. I don't know if this makes a difference or not, but thanks for responding. Good luck on your situation!
We had a plumber finally come out this afternoon and it appears the problem is fixed! The reason for our plumbing issues was roots. He broke all the roots up and everything is working perfectly. He only charged $150!