Understanding the Normal Fetal Heart Rate
If you are pregnant, you probably know that monitoring your baby’s heart beat is one of the best ways of ensuring that he/she is healthy and developing normally.
There are several ways of calculating the baby heart rate: going to your obstetrician for an ultrasound check up, having your doctor listening to the fetal heartbeat by using a stethoscope or buying (renting) a fetal heart monitor for home use.
While medical facilities use different types of fetal monitors (external and internal), the devices designed for home use are user-friendly and non-invasive. Their functioning is based on the Doppler effect – they use ultrasound waves in order to detect and amplify the sound of the heart beat so everyone in the room could hear it. The fetal Doppler (also called pregnancy Doppler, baby Doppler or home fetal Doppler) will allow expecting parents to monitor the fetal heart beat as often as they want, this way being reassured that their child is safe.
However, one problem arises: monitoring the fetal heart tones is useless unless we can correctly interpret the fetal heart rate range.
What is the normal fetal heart rate?
Actually, the normal heart rate of an unborn baby fluctuates depending on the stage of the pregnancy.
Specialists say that it’s possible to hear the beating of a baby’s heart by the 5th week of pregnancy. At this moment, the normal fetal heart rate oscillates between 80 and 85 beats per minute (BPM), being very close to the mother’s heart rate. From week 5 to week 9 (for about one month) the baby’s heart rate will gradually increase with about 3 – 3.3 BPM every day. When you reach the 9th week of pregnancy, the normal fetal heart rate should range between 155 and 195 BPM.
After the 9th week of gestation, the baby’s heart rate begins to decelerate until it reaches a rate of 120 – 180 BPM (in the middle of your pregnancy).
In the last 10 weeks of pregnancy, a slowing of the heart rate is normal as well.
Just as your heart rate varies depending on various factors (active and resting phases, sleep, stress etc.), so does your baby’s. Small oscillations are normal. It has been proven that stress and chronic anxiety along with changes in the heart rate and blood pressure of the pregnant woman can affect the heart rate of her baby as well. If you begin to worry too much because of your baby’s heart rate, speak to your doctor about your concerns.
For hearing the heartbeat of the unborn child at home, without the help of a medical professional, many expectant mothers use Doppler fetal heart monitors. However, don’t forget that this device will not ‘hear’ the heartbeat before the 9th or 10th week of pregnancy. Some parents wonder if a baby Doppler is safe for the child and the mother. While it’s very difficult to state without a shadow of a doubt that ultrasound waves are 100% safe for the human body, most specialists agree that there are no risks associated with the use of a fetal Doppler.
If you’re using the fetal monitor for the first time, you should know that hearing the heart beat depends on many factors. For example, if you’re slim it will be easier to ‘catch’ the heartbeat, while overweight women find it harder to hear it.
A home baby heart monitor cannot heart the heart beats before the 9th week of pregnancy, However, the ultrasound can ‘see’ the beating sooner – at 4 or 5 weeks after conception.
During each prenatal visit to your doctor, he or she should check your baby’s heart rate. This monitoring method is one of the best ways of checking the condition of your unborn child. There are two ways of monitoring the heart beat:
- Counting the heart beats during one minute
- Counting the heart beats for 15 seconds and multiplying them by 4.
It’s not very hard to interpret a fetal heart rate. You can find online many useful charts that display the normal range of a baby’s heart rate. However, it’s not advisable to monitor your baby too often: every minor change (which could be perfectly normal) can make you anxious, being the cause of unnecessary stress. You can use your own fetal heart monitor from time to time, but allow the specialist to decide which is the condition of your child – after all, there are so many factors that could influence the heart rate of your baby!
