Atenolol is usually avoided during pregnancy. It CAN be taken, but it will significantly raise the risk of growth development issues while in the womb. In other words, the baby's growth may be slowed due to atenolol. I was taking it when I conceived my son, and even though they switched me to propranolol during the 2nd trimester, I spend the entire pregnancy under the care of a Maternal Fetal Medicine specialist who monitored my son's growth to make sure it wasn't affected.
It wasn't :-). I took beta-blockers for the same reason as you...my resting heartrate used to always be about 110-125, but the bb's brought it down into about 80-90.
other options considered safe during pregnancy are metoprolol and propranolol. propranolol is preferred because it has the highest reported cases of usage during pregnancy without complication. so I would ask to switch to that NOW...let your doctor know that you are trying to conceive.
good luck in January! I hope you will keep coming back and update us with your progress!
(in case you wonder my son was born 7lbs 10oz and 20 inches...not small at all :-) ).