Hi,
It's a really tough one making these decisions about whether to share.
Luckily for me, I work in the civil service and my dept gives paid leave for fertility related appointments. I've been very open with my manager (who actually had IVF herself so is incredibly understanding) but I also know it's not going to impact my job security/promotion prospects, which I appreciate is a concern for some.
I would say working from home when you start stims injections is a good idea. You can get very bloated towards the end and sitting or standing can be uncomfortable, some people can get upset stomachs or excess gas, and I think generally your emotions are a bit all over the place. You'll have lots of scans and you won't be able to plan your egg collection date perfectly as it could change depending on scan outcomes, you may only have 48 hours notice.
You will need the day of egg collection off work because of sedation, and I'd plan to be off sick the following day too as you'll be sore and bloated and maybe still suffering from sedation after effects. The bloating can take a while to go down (my first round I couldn't sit up comfortably for 4 days afterwards due to the swelling so I didn't work those days). I'd also bear in mind that the updates from the embryology team in the 5 days post egg collection can be upsetting if not what you want to hear, so again working from home can help give you the space to process this.
I took the day after transfer as holiday to chill out as I was upset we only had one embryo to transfer, but then carried on working after during the 2ww. If you're in an office job I really think you'd be okay working unless you feel unwell, you want the time to pass quickly! If you do need sick leave after transfer, telling your employer will help as they have to record it as pregnancy-related (same as for the 2 week period after a negative test - same as with a miscarriage) so it can't be held against you if you have attendance monitoring processes.
I hope all goes well and I hope if you do tell work that they are supportive.