Sinus tachycardia in pregnant women refers to an arrhythmia, and it is the mildest and most common type of arrhythmia, which is sinus tachycardia. A normal human heart rhythm is sinus rhythm, and the number should be 60 to 100 beats per minute. If it exceeds 100 beats per minute, it is called sinus tachycardia. In pregnant women, the presence of sinus tachycardia often indicates that the pregnant woman may have a heavy heart burden, especially in the late stages of pregnancy, which may lead to a faster heart rate. It is possible that in the late stages of pregnancy, more nutrition is needed and the nutrition cannot keep up and the body becomes anemic. Once anemia occurs, the heart becomes compensated. Sinus tachycardia will appear on the ECG. Therefore, if a pregnant woman develops sinus tachycardia, the first thing to consider is that it may be caused by a heavy heart burden. Another condition could be anemia caused by nutritional deficiency or inadequate nutrition, and the presence of in-motion tachycardia.