I took my bitch for her annual health check and booster at 10 weeks post whelping, and asked the vet when she could be spayed. He said we should wait another 6 - 8 weeks, or she would come back into "full milk". My only concern about waiting that long is that she might come into season again. Is the next season usually delayed after whelping? And why would spaying cause her milk to return - logically, I would have thought it would have the reverse effect?
Cathy.

You say she's 10 weeks post-whelping. How long does she usually go between seasons? Longer than 20 weeks or so, I'd imagine. Even if she has regular 6 monthly seasons (unusual!) that would take her to 26 weeks. The reason your vet wants to wait is to make sure her hormones have completely settled down - any interference can throw everything haywire. Even an unmated bitch shouldn't be spayed till about 14 weeks after the start of her season.
:)

You are right Cathy a spay will stop her from producing milk as her ovaries are removed at the same time, it is always a risk with a C section any damage to the ovaries can cause a bitch to dry up or not produce milk at all.

I had my bitch spayed when the pups were 10 wks old as she was known to come into season again by the time her pups were 12 wks and my vet is happy to spay this close to a season, in fact he prefers it to a midseason spay. 

I rang the vet's again this morning to discuss this further. They are adamant they won't do it before 16 weeks post partum, as they say it could trigger a phantom pregnancy.
Cathy.

Trust your vet.
:)

I don't get theri maths at all.

16 weeks post partum plus 9 weeks pregnancy plus two weeks from start of season to amting would make that 27 weeks from the last season. 

Now my bitches come in season about every 27 weeks, so would be about due a season just when your vet would be willing to spay, don't sound right6 to me!!!!

My vet has said once pups are about 8 weeks (which gives the bitch at least 8 weeks before next season due).

Exactly, Brainless, that's what I'm worried about. I've rang two other vets who would do it now provided she's no longer feeding - and she's just about stopped, teats are shrinking nicely. So much as I don't like changing vets, I think I shall have to because I want this surgery done asap!
Cathy.

Update and happy ending! :) :) :). Maggie has been spayed today - at my usual vets. I rang them and said that I was thinking of going elsewhere....and, surprise, surprise, I got a message to say that they would be happy to do the op there. I'm SO relieved....I just didn't want to have to wait several more months if she had come into season again.

Now my only difficulty is keeping mischievous puppy occupied to give her some peace to recover...

Cathy.