NEET BIOLOGY

Detailed explanation-1: -The average fetal heart rate is between 110 and 160 beats per minute. It can vary by 5 to 25 beats per minute. The fetal heart rate may change as your baby responds to conditions in your uterus. An abnormal fetal heart rate may mean that your baby is not getting enough oxygen or that there are other problems.

Detailed explanation-2: -By 20 weeks the average (SD) fetal heart rate is 140 (20) bpm with a gradual decrease to 130 (20) bpm by term. In the healthy fetus the heart rate is regular, usually remains between 110 and 180 bpm, and has a beat‐to‐beat variation of 5–15 bpm.

Detailed explanation-3: -The average heart rate for baby boys in the first trimester was 154.9 bpm (plus or minus 22.8 bpm) and for baby girls it was 151.7 bpm (plus or minus 22.7 bpm). In other words, this myth is busted. There was not a significant difference between male and female heart rates during early pregnancy.

Detailed explanation-4: -A very fast heart rate may be caused by abnormal firing of the nerves that are responsible for the heartbeat. If the heart beats too fast, contractions are shallow and not enough blood is pumped with each heartbeat. As a result, the fetus can go into heart failure.

Detailed explanation-5: -21 Weeks Pregnant: Your Baby’s Development This week, your baby’s heartbeat is now loud enough to be heard through a simple stethoscope, but the beat can be difficult to distinguish from your own. Listen for the faster rhythm-a baby’s heartbeat is 120 to 160 beats per minute, about twice as fast as yours.