AFAIK, (and I've looked!) ACOG doesn't have much to say about pregnant women and heavy strength training. ACOG puts out the guidelines that most US OB practices follow and they offer general exercise guidance.
In general:
For most healthy women it is okay to continue the exercises you are used to doing.
Stay hydrated
Avoid closed glottis lifting (in other words, breathe, don't hold your breath!)
Avoid lying flat on your back after the middle of pregnancy
Don't get hurt (common sense, let's not fall of the pull-up bar)
Know that in late pregnancy, your center of gravity will shift and your joints will be lax and things that you could do in the first trimester might be too uncomfortable in the third. (A power clean at 34 weeks might be a little uncomfortable....one should always listen to one's body)
All of these guidelines assume normal pregnancy. Previa, preterm labor, hypertension, etc., will obviously interfere.
These are general and nonspecific guidelines and do not replace your discussions with your own personal midwife (or OB/GYN if you must)