I was told mid cycle was the best time to have a smear test but i realise that this can affect ttc.
I had a smear in July which was inconclusive as they had not collected enough cells. I had to wait six weeks for result and then another couple of weeks before it was a good time to have another smear test. I am due to start tx in december and my smear result is not due back until the end of November. Just thought I would mention this as like you I put it off a few times because i didn't want to 'waste' a month. Now i realise how long the results take i would say it would be best to get it out of the way as soon as you can then you can just forget about it.
my clinic would not do tx without an up to date smear test because if there is a problem it needs to be treated before fertilty treament otherwise any abnormal smear result will not be treated until after the baby was born assuming a pregnancy which is nine months , thats a long time to wait to treat an abnormal smear
I have just had a smear test last week. The nurse was very adamant that she wouldn't do it if there were any chance of me being pg, i was advised to go mid cycle but a couple of days before hand shouldn't be a problem, i have to wait 4 weeks for my result.