Growth plates, spaying and cancer risks

[Glitchymn1]

I have a staffie, she’s 7 months and started her first heat 12/10/25 and still going, so imagine it’ll last until this weekend.

So we’ve waited for this one heat so that her body matures. I’d hoped it would have been closer to the 9 month mark, so I could get her spayed before the second season but after 12 -15 months old ideally.
I’m now wondering whether to wait for the second season to lessen the chance of joint issues or pay to have her x-rayed and the growth plates checked? I know waiting for a second season increases chances of mammary cancer from 8% to 26%. So I’m tying myself up in knots. I don’t know what to do for the best, obviously will see a vet for advice but hoping to get some advice from here too.

Has anyone had their dogs growth plates checked?
I’m wondering if the vet will think I’m insane asking for this. (Our last dog was neutered at 12 months and had cruciate disease, cruciate tear, arthritis from age 7 which we did have an operation and meds for but it really did change his life afterwards so I’m cautious).

So for her breed, the big risks are jumping and twisting when chasing balls. She's powerful, and cruciates are really prone to twisting so the force she can put through her knees can cause issues. I would spay at about 11 months (you should still be in the clear re the second season, as long as she's not showing signs on the day it can go ahead but ideally would be at the mid point between seasons). So in short, I'd take the benefits of reduced mammary cancers by spaying before her second season but the crucial thing is no ball chasing and minimising harsh stops and turns.

A paper in 2012 concluded that the evidence on the impact of neuter on mammary cancer was weak and 'not a sound basis for firm recommendations.'

There also isn't much really conclusive evidence of the impact of age at neuter on cancer risk and the chance of joint disease, though there is evidence that it varies by breed and sex. Some researchers recommend delaying neutering for some breeds.

Personally I now wait until my dogs are mentally and socially mature, so age 2 at minimum. My younger dog was four before I had her spayed, as she was slow to mature.

@Sillysoggyspaniel thank you - we don’t throw balls at all. She’s an absolute bugger for jumping off furniture though and onto rugs, at least it isn’t direct onto wooden flooring I suppose. I don’t let her off lead, we have a large garden which she sort of potters in. The zoomies have stopped and she’s actually a chill puppy unless visiting humans come over, then she gets very excited but will settle if you cuddle her.

@EdithStourton thank you too. I feel like I’m doomed either way at the moment, worried about pyrometra and phantom pregnancies. Maybe I’m overthinking.