If you are doing the injection, yes, don't take while on TOM, but for drops, I was told that these days, those who are taking hcg drops continuously taking them during TOM and it did not affect their weight loss.
I took the hcg drops on my Tom and it made me so hungry and tired I had to stop them. I restated them the last day of my cycle without that effect. I literally could not stop eating when taking drops while on Tom. I would recommend skipping it then. I think everyone is different but that was my experience with it .