Brief Answer:
Mostly physiological.

Detailed Answer:
Hello,

Thanks for posting your query.

Racing heart or 'palpitation' as it is called is an usual phenomenon during pregnancy and can be due one of these several causes---

---anemia
---tiredness
---anxiety
---dehydration
---associated thyroid anomalies
---hypertension
---heart disease.

During the early second trimester as you are in, hypertension and heart disease do not cause much symptoms; in fact, symptoms appear when the fetal demands increase as in the mid-trimester toward the late trimester. These can easily be identified through clinical exam and lab tests. Previous history is also significant.

After trying to identify the notable causes, holter monitoring may be done to look for the specific type of abnormality and relate it to a specific cause.

Please see a cardiologist in consultation with your obstetrician to evaluate the condition further. Most often, this palpitation in pregnancy is physiological.

Hope your query has been answered. Please feel free to contact for further clarifications. I will be happy to help.

regards,
Shanti.V.

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