Keto diet vs 21 day fix diet

Hi everyone, I am just looking for input on diets for weight loss. I will be starting HIIT in 2 weeks and will be starting home work outs next week before hand which include kettlebell, yoga, sit-ups, and push-ups. I am unsure how long it will take to conceive since my ectopic my first period will be here shortly (hopefully). I have done the 21 day fix in the past and found it easy to follow and cheap. But I have heard of great results with keto. I am 5'6 and weight 180 so my bmi is obese ( I carry in my stomach). Which diet would you recommend? Is keto even safe once pregnant?? If it isn't will there be a big change/impact on my body switching from keto to clean eating which includes healthy carbs: whole grain rice, quinoa etc. Thanks for your help!