Hello,
Thanks for posting your query.
Whenever we are over exerted or the heart has to work harder due to any cause the blood flows forcefully in the major blood vessels like aorta , subclavian etc which might be felt as throbbing pulsations .
Like the palpitations of the heart beat these might be physiologically felt on exertion and pregnancy which causes a hemodynamic overload on the heart .
However painful pulsations also might be suggestive of an underlying serious cardiovascular condition like aneurysm or arteritis , hence should be further evaluated.

Most probably it can just be palpitations or exaggerated pulsations that you feel due to the hormonal and hemodynamic changes of pregnancy . This can be felt as feeling of an impulse travelling through the body. Palpitations may be normally felt if you are overexerted. Chemicals like adrenaline, alcohol, caffeine, amphetamines, and other drugs all cause palpitations. Disease (such as hyperthyroidism and pheochromocytoma) or mitral stenosis, panic disorder all cause a feeling of an impulse travelling through the body. Palpitations may be associated with heart problems, anemias and low blood pressure.
Go over these possibilities with your doctor. It is difficult to comment beyond this without examining.
Considering you have been examined by your doctor and assuming that you have been evaluated thoroughly like blood pressure , lipid profile , thyroid profile , ECG etc I would most probably attribute it to the physiologic changes in pregnancy and would go for further evaluation ( Doppler ultrasound etc ) only if the problem persists post delivery or if it worsens progressively.
Till then I do think that avoiding stress , strenuous physical activity and avoiding alcohol would be most beneficial in decreasing such episodes.
Hope I have answered your query.
Kindly accept my answer in case you have no further queries.
Regards

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