A friends bitch is due in season in a month or two and they are planning on giving her the injection to stop her coming into season, how long before her season should the injection be given, and how long should it prolong it for? Are there any complications?
It can cause a lot of problems and I'd never do it again. I did it because of an important show -silly. The bitch never had a normal season again. Eventually (after more than a year) she had a totally silent season, developed a mammary tumour and hyper thyroidism and had to be spayed. Thankfully it was after she'd finished having pups anyway, but even so. I know of another bitch who didn't have a season for 2 years.
Done it once, 10 years ago, when we had just moved house & she came in season & we had a male but would never do it again. Luckily the bitch did have proper seasoons & had a litter but it can cause infertillity & as others have said irregular seasons, amoungst other complications.