A pregnant women who is 7 weeks from her LMP comes in to the office for her first prenatal visit. Her previous pregnancy ended in a missed abortion in the first trimester. The patient therefore is very anxious about the well-being of this pregnancy. Which of the following modalities will allow you to best document fetal heart action?
High-Yield Explanation
Vaginal ultrasound can detect fetal heart action as early as 5 weeks of amenorrhea. With a traditional, nonelectric fetal stethoscope, heart tones can be heard after 19 to 20 weeks gestational age. With appropriate Doppler equipment, fetal heart tones can be usually be detected by 10 weeks gestational age.