My AMH is below 4, NHs here done measure if it falls below 4 and they just give you the highest amount of drugs that they do for ivf.
I am pregnant on m first attempt. I got 12 eggs all looked great and dh's sperm looked good, but only 1 fertilised. We were advised that future goes would need to be icsi. They basically couldn't give us a reason for almost complete failure. However they did say, sometimes the sperm looks fine...
I'm of the opinion that due to that we'd never have conceived naturally. A friend of mine had very low AMH and got pregnant naturally having failed ivf a few times. I think you really need to be having lots of regular sex, and the sperm must be fantastic. Dh had never had a problem with his and it was considered fine. The morphology was always below 9 but the WHO says that's fine. His count was always around 30million, which is fine but not amazing wither. I also had the endo scratch which is said to improve implantation but up to 20% and I also had acupuncture weekly and twice in the day of transfer.