I can answer this from another perspective...
I don't want to ovulate at the moment, due to endo. I was on desogestrel POP for 9 years which totally stopped ovulation and all was very quiet on the ovary front.
Starting HRT, I tried stopping desogestrel and taking 100mg utrogestan continuously. But after 5 weeks, the ovaries woke up from their long sleep
and started firing shooting pains everywhere in the process (which faded away) but then I got my endo twinges back again. I gave it a few weeks to settle but no luck.
I restarted desogestrel which stopped it all within a week. Continued desogestrel for 6 weeks to shut it all up again...
Then stopped desogestrel again and now trying 200mg continuous utrogestan. So far I'm at 2 weeks and all is good.... My estrogen is also lower this time round - it was at 50 then and I've had to reduce to 37.5 now.
So - my conclusion from this so far is that 100mg even continuously isn't enough to stop ovulation. But 200mg hopefully is. Unless you want to go on continuous at a higher dose, or to add in the desogestrel POP, I'm not sure you can stop ovulation. You can use the POP at the same time by the way, some women use it for contraception whilst on HRT.
By the way, Lara Briden is a huge fan of ovulation and reckons we should all be ovulating for as long as we can. If I didn't have endo (mildly) I'd be trying to do that. I am sorely tempted anyway but it would probably be a stupid thing for me to attempt...