All of the answers provided are great! In addition to what’s already been said I just want to share my own experience w/ being pregnant & working out… I was already conditioned to high intensity exercise & my doctor told me I could continue doing what I had already been doing w/ the exception after the 1st trimester no lying flat on my back exercises. I remember a man at the gym telling me my baby would be strong b/c of my working out – at the time I thought he was being funny but sure enough my little girl came out strong & 3 yrs later still strong. She even has nice definition in her shoulders it’s awesome! After the 1st trimester was over I did a lot of mid-line cable chops for abs & let me tell you my obliques were crazy strong (lol) I also did standing cable crunches w/ the rope attachment. I’m sure my strong core played into my easy birth. I had my daughter at home w/ NO complications! With all that being said if your client has been training before pregnancy continue to train her as usual just adjusting her positioning as she moves through her trimesters!