I have a one year old purebred husky who recently got spayed a week ago. After having a friend watch her for a day I found out she was pregnant about a month later. It is a long story but she ended up having her first litter at about 9 months of age. After about two months I decided it was time to get her spayed to prevent this from happening again.
She recovered well, didn't show signs of pain and gained back her energy a day after surgery, she never even licked the area.
Elsa has always been a very friendly dog, never barked or bite. When I take her on walks other dogs would growl at her but she would just look and not say a word. A couple of days ago I brushed her and a majority of her hair fell off. It was so alarming I took her to the vet and was told it was due to hormonal imbalance from having her litter and getting spayed.
I took her on a walk today, and the moment she saw a dog she starting pulling trying to escape from her leash. As the dog approached she started growling and charging. It happened everytime a dog passed by. I've never seen her do this before, and all the dogs she growled at were smaller breeds.
After the encounters she would start pulling much harder and basically misbehaving.
Has any had this problem before? I've searched but never found answers from legitimate veterinary articles, only alot post from concerned owners like me.

I do not personally have this problem with my girl. However we do have a member here who has a rescue, that she believed had a litter just prior to being spayed, who is leash aggressive/reactive. She is normally on the forum during the day, if she does not see this thread I'll give her a pm. I do know that she did have a trainer come in and help address the problem. I'd rather have her help you, rather than myself, but I wanted you to know that somebody has seen this and I know others will want to help.

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Thank you very much for your help! I did seek out a trainer but won't be able to get on her schedule until two weeks from now, so I am still looking to see what I can do for the time being. I am now very cautious when walking her and don't know if I should take her to a dog park she used to frequent.

Elsa, would you mind updating your profile, please. As you can see, we're scattered across a good part of the globe and having some idea of where you are can help us help you better Okay, maybe not with this particular problem, but it's always nice to know the location of the people we're talking with - who knows, maybe you're close enough to others for a play date?

The trick to leash reactivity and aggression is trying to get to the root of what causes it. What has changed since she started having issues. A hormonal imbalance can change the way she perceives other dogs and the way they perceive her. During her mating something could have happened that scared her causing her to harbor nerves she didn't have prior. Or the imbalance she currently suffers has triggered issues in other dogs and problems have arisen from it. has she had any scraps with other dogs recently or since the mating. Does the friend recall how the mating went? Was it violent? has she been near the father of the pups since the mating? if so, how did it go? A lot of trauma has happened to her recently between having puppies and then getting spayed. As her routine goes back to normal and you get the hormonal imbalance under control she may settle back into her old self. If she doesn't though then a trainer is a good way to help you work through finding her triggers and getting her back to positive standing with other dogs.

I am curious what the vet's answer to dealing with her hormonal imbalance was? A med? Just waiting it out?