Can A Fetal Heartbeat Disappear And Reappear?

By Sarah •  Updated: 08/05/22 •  6 min read

New mothers can be both excited and nervous about pregnancy. It is an experience none will ever forget and, for first-time mothers, it comes with extra anticipation as well as questions and concerns. 

Ultrasounds are particularly exciting because you can see how the baby is developing and the doctor gives you an update. However, it isn’t always good news. Sometimes, the doctor detects a problem and no news can be worse than failing to find a heartbeat. 

Can a fetal heartbeat disappear and reappear? Yes, a baby’s heartbeat can disappear and reappear during the early stages of pregnancy. Typically, this would happen when you are less than 12 weeks pregnant. It is rare but can happen. 

Can A Fetal Heartbeat Disappear And Reappear?

What Should You Do If The Fetal Heartbeat Disappears?

There are many logical reasons why an ultrasound may not detect a baby’s heartbeat. One thing to do is to remain calm. The second thing to do is to get another ultrasound done a few days or up to a week later. You may even want to get a second opinion from a different doctor.

One mother-to-be posted on a chat board about her experience. Her doctor found a good heartbeat at 6 weeks pregnant but found no heartbeat at 8 weeks. A D ; C was scheduled but the future mom wanted another ultrasound to be sure. One was done three days after the 8-week scan and they found a healthy heartbeat. 

Her advice was to always trust your intuition and challenge the doctor for a second opinion. 

Can An Ultrasound Miss A Baby’s Heartbeat?

Two types of ultrasounds exist. There’s the transvaginal ultrasound and the abdominal ultrasound. The transvaginal is an internal ultrasound so it is more accurate and can find a heartbeat at 6 weeks pregnant. However, there are cases where even the internal ultrasound can’t detect a heartbeat until you are 7 or 8 weeks pregnant.

The abdominal ultrasound does a better job at 8 weeks but can’t be completely accurate until your are 12 weeks pregnant.

The fact is that sometimes it’s too early into the pregnancy to detect a heartbeat.  That is the most common reason for failing to get a heartbeat. It doesn’t mean you will miscarry.

The chances of miscarriage are greater if your doctor doesn’t find a heartbeat a week later with another ultrasound but, even then, it doesn’t mean you will definitely have a miscarriage.

Reasons For Failing To Find A Fetal Hearbeat

Some common reasons the ultrasound may not get a heartbeat are:

Another common issue is the mother is overweight. That can cause problems using the ultrasound.

Can Being Overweight Be a Cause of Not Hearing a Heartbeat?

Weight problems can make doing an ultrasound challenging. There is an extra layer that can get in the way of hearing a heartbeat. The heavier you are, the more difficult it will be to get a good picture and sound of the baby. This is especially true when using an abdominal ultrasound. You may need a transvaginal ultrasound to get a good view and sound of the baby.

What Is a Missed Miscarriage?

A missed miscarriage is when there is a miscarriage but the woman hasn’t had any symptoms letting her know it’s happened. She doesn’t have any pain or any bleeding and feels fine just as she has so far in the pregnancy. 

This type of miscarriage can be an emotional shock for the woman because she didn’t know it happened until either the ultrasound shows the baby has died or until she has a the bleeding and pain that comes with miscarriage. 

She still feels pregnant and doesn’t understand why there haven’t been any symptoms. Feeling pregnant but knowing there isn’t a baby can take an emotional toll.

Is It Dangerous to Wait on Another Ultrasound?

Most doctors will recommend you get another ultrasound a week after the first one shows no fetal heartbeat. This is because sometimes you are too early in the pregnancy to hear it or maybe the baby is difficult to detect because of position or the uterus position. 

This is a conservative and practical route to take because waiting will not hurt the mother but a D ; C, which is an abortive procedure, will end the pregancy.

It isn’t dangerous to wait, according to all the medical research. You could miscarry before the next ultrasound but you may not. The second ultrasound is where there is more certainty. A lack of a baby heartbeat on the second ultrasound may provoke the doctor to ask whether you want to miscarry naturally on your own or have a D ; C scheduled. 

Most women going through this suggest getting a second opinion and waiting longer because of the high likelihood that you are too early in the pregnancy to find a heartbeat. While a heartbeat can be detected as early as 5.5 weeks into pregnancy, doctors say you can’t be sure about a heartbeat until you are 12 weeks pregnant. 

Some medical professionals suggest waiting until you are at 12 weeks before getting an ultrasound at all because having them done earlier causes anxiety with the increased chances of hit and miss in finding a heartbeat. Early ultrasounds may be exciting but tend to not be as revealing as new parents hope. 

Final Thoughts

There are many myths and mysteries surrounding pregnancies. One question that has puzzled many people is whether or not a fetal heartbeat can disappear and reappear. The answer to this question is yes, fetal heartbeats can disappear and reappear. However, there is not much known about why this happens and it’s usually in the early stages of pregnancy.

Sarah

Sarah is the driving force of Sweet Miles, a lifestyle blog that focuses on running, parenting, and food.