I am 22, 8 months pregnant. Very healthy, always have been. Weight is normal, don't use caffiene, alcohol, chocolate or any stimulants. Have had tachycardia since childhood, but was told early on not to worry about it since it won't hurt me. Since being pregnant, (first time), the incidences have increased and not unusual to last for 2-3 weeks, with rates near and over 200 bpm.