Few days back my neighbor came to my home and she complained that she is having fatigue, breathlessness, palpitations, when I measured her B. P it was 118/76 mm of Hg and her pulse rate was 124 pulse per minute. She was in 3rd trimester.
Remember tachycardia in pregnancy is normal, no need to worry about it much, however there are few conditions where you need to worry which I will tell you later in this article, normally 20-25 heart beat increases in pregnancy, it all happens due to changes taking place in pregnancy.
So tachycardia in pregnancy can be due to Anemia ( in this patient haemoglobin was 9 so obviously she was anemic in pregnancy Hb 11 or below is considered anaemic. Other causes are may be sepsis, fever, anxiety, thyroid problems, dehydration, pulmonary embolism, rupture of placenta or uterus but here you will have other signs and symptoms, heart disease, respiratory diseases like asthma, etc. So there is no harm in visiting your doctor once if you have all these symptoms.