Hi Nut,
You sound like a very responsible rabbit slave. I have a rescue and see what happens when rabbits aren't spayed/neutered. We have a male that has survived testicular cancer.
In the hands of a skilled and experienced rabbit vet, rabbit surgeries have become much safer. But always remember there is risk in any medical prodecure so the key is to determine if the benefits outweighs the risks. We have done the spay/neuter thing hundreds of times. I have successfully sedated baby cottontails, and they are notoriously more delicate then domestics, at a fraction of the weight of your bunny. Spays can be done starting at about 6 months assuming she is in good health otherwise. There are some things to discuss with your vet prior to the procedure. I have been doing this a long time.....and if I see a new vet, this is what I am looking for.
Ask about removing food the night before. Many times the front desk people will tell you that out of habit or lack of education. Food and/or water should not be removed. Some vets will ask that pellets be removed at least two hours before the sedation but your rabbit should have access to hay and water at all times....we have had rabbits eating hay as they started the sedation. Ask about anesthesia. Most vets use an older gas inhalent known as Isoflourane. It is widely used and is safe. Some of the more modern clinics use a newer gas inhalent called Sevoflorane. If you have a choice...go with the Sevo. We have been very pleased with it and the rebound time after recovery is much faster. Some of the more progressive vets also use an injectable anesthesia. You will read in many articles that these are unsafe. Simply not true. In fact, this anesthesia can be reversed with an injection of a reversing agent. We normally use the injectable in longer duration procedures such as complex dental issues. Ask abou sutures. We insist on laser surgery. There is some debate in the vet community about the benefits versus additional cost of laser. We always take the laser with spays. The incision is clean and there is less blood loss. With the clean cut, our vet uses internal self-dissolving sutures and makes the final close with surgical glue. No sutures to chew on or become infected....or that need a follow up to be removed. Insist on aggressive post op pain management. Most vets offer metacam. While this is an excellent drug, in my non-professional opinion based on our many surgeries, it is insufficient. I insist on narcotics. My girls are always eating within hours after the procedure.
In my opinion, and as per our policy, we always feel it is in the best interests of the rabbit to have her spayed. We do not breed here at all so the our feeling of our vets and us is that if those parts are not there, they can't cause problems down the road. It will not affect her growth but might help her disposition after she becomes hormonal. Not only will it eliminate any possibility of female health issues, it will prevent her from the stressful events known as false pregnancies. Hope this helps with your decision.
Randy