>I'm looking at other places to get progesterone done but cytology was another option.
Progesterone and cytology complement each other but they don't really replace each other as far as timing goes.
Cytology tells us when we are in proestrus, estrus or diestrus. Ovulation occurs during estrus, but cytology can't tell us when exactly, during estrus.
The first part of any heat cycle is proestrus and this can be as short as a few days or as long as 20 days. On her last cycle, my bitch was only in proestrus up to day 5. After that, comes estrus. At some point during estrus, she will ovulate - but we don't know when exactly and can't tell with cytology. She may be in estrus for some time before ovulating, or she may come into estrus and ovulate right away. So cytology still leaves a lot unexplained.
Although my bitch was in estrus from day 5 last time, she wouldn't stand and flag properly for the stud until day 11. So cytology wasn't much help for me - after just one or two slides, she was in estrus and it couldn't help me further with ovulation. If I had a bitch with a really long proestrus, on the other hand, then cytology is incredibly useful because you can track that this is what's happening and not attempt to breed or even do any progesterone until she goes into estrus.
And then there is some variation on the slides between bitches - some bitches show progression in the slides, with the cells becoming further crystalised and opaque and the nuclei disappearing (cells becoming anuclear) - whilst other bitches ovulate without those additional changes. So you ideally need to know your bitch as well and to have followed her on a cycle you're not breeding on.
Actually doing the swab and preparing the slide is not very difficult. The skill lies in looking at the slide and interpreting it. That's where having access to many other people who are all very experienced at doing cytology (Avidog) is invaluable.
If you were doing to use cytology 'properly', the way to use it is to use it during proestrus to determine when proestrus is over and you're into estrus. When you see that you're into estrus, then you can start doing progesterone (with a reliable lab!). This reduces the overall number of progesterone tests substantially because you are not doing all those early tests which aren't showing much happening. Then, after breeding, you resume cytology to determine diestrus and get an accurate whelping date to within 24 hours.
Other things to think about are nutrition - foods containing flaxseed, green beans, peas and other plant phytoestrogens have been shown to disrupt hormone levels. BPA can also. Water contamination if on well water or similar. And so on. Again, Avidog is brilliant for diagnosing all this and provides guidelines on optimal diet for breeding.