Can you tell me when I can expect my dogs next heat(approx)

She came into heat on March 1 and delivered her first litter on May 15th.....When can I expect her next heat???

How long does she usually go between seasons? My bitch had a litter on May 1st and came into season last month, but she came in on time as if she had never had puppies. It usually doesn't matter if they have had a litter or not, they usually come in at the same time.

still went for gollie to come in the last season she had was dec 9th 2006 then a litter in feb 2007,

one of my fcr was 4 months after her litter another bitch 6  to 8 months

With my own bitches I have found their seasons delayed by about a month to what they would have been expected if they had not had a litter.  Mine usually come in about every 6 months so if they had a season March I would expect the next season September, and if they had a litter then about October.  Or putting it another way by the time pups are five months old.