this is my second pregnancy, and i had a sonogram at 9weeks1day, and the baby measured perfectly. had a heartbeat. when i went back to the doctor the next week, he was unable to hear the heart beat on the doppler. he didnt seem worried, just scheduled me to be back next month. is this unusual? with my first dayghter i was able to hear a doppler heartbeat at my very first prenatal visit. at about 8 nd a half weeks.