New program

So I’m signed up to start a new HIIT workout program but just found out I’m pregnant. I’m in so-so shape and this program would kick my ass if I went all out. For most part I’ve seen as long as I don’t get super winded/raise my heart rate about 140-160 I should be able to continue.

They will and can modify the work outs for us, but I’m worried little bit to start a new program. I’m overweight and my last pregnancy I lost weight during my last trimester. I’d just like to start off better than last time.