The normal heart rate in non-pregnant women is between 60 and 100 beats per minute. During pregnancy the heart rate increases an average of 15 beats per minute. Most of this increase comes at the beginning of the 3rd trimester and remains for the remainder of the pregnancy. Therefore, to know your estimated heart rate at 22 weeks, you would need to know your resting heart rate before becoming pregnant and adding 5 to 20 beats per minute. Your doctor is the best one to advise you on any abnormality of your heart rate.
Dr. David Stewart, Medical Director, Heart and Vascular Institute, Providence Everett Medical Center
found on www.providence.org