If you are wondering at how many weeks the baby begins to beat in the womb, when the heart develops in the fetus, the baby’s heartbeat is heard from 7 weeks and older, read on.
Fetal heart development continues throughout pregnancy and even after a short period of time. At 5 weeks, the embryo forms two heart tubes that fuse together. Blood flows through this tubular “heart” and cardiac activity begins. Parts of this tube will go on to form all the structures of the future heart. There are things you can do to protect your baby’s developing heart, like avoiding cigarette smoke, alcohol, and certain medications.
When does your baby’s heart start beating?
A baby’s heartbeat begins 4 weeks after conception, or 6 weeks after the first day of the last menstrual period.
Seeing your baby’s heartbeat when you find out you’re pregnant may be one of the first milestones you’ve been looking forward to. You don’t have to wait long. A baby’s developing heart starts to work quickly because it is needed to deliver oxygenated blood and nutrients to other developing organs.
But at 6 weeks of pregnancy, the heart is not fully developed. For this reason, the cells in the embryonic heart tube are described as “cardiac activity” rather than a heartbeat.
When can you see your baby’s heartbeat?
About 4 weeks after conception, or 6 weeks after your last menstrual period, the rapid pulsation of the embryo’s developing heart tube can be seen on an ultrasound.
If you have a first-trimester ultrasound (perhaps because you had a complication from a previous pregnancy), it’s possible to see heart activity that early. This ultrasound can also be used to check for heart problems; this can be valuable if there is a family history of congenital heart problems.
If your doctor can’t see your heartbeat in the future on your first ultrasound, it may be too soon to see your heart move. (This is common!) If there is a “fetal pole” (embryo visible) and no heart movement, you may have a miscarriage. Your obstetrician or midwife will talk to you about what your personal ultrasound means and what your next steps are.
When can you hear your baby’s heartbeat?
If you don’t have an early ultrasound, you’ll likely hear your baby’s heartbeat at a prenatal visit between 10 and 16 weeks. Your doctor will use a fetal Doppler, a small handheld device that is pressed against your abdomen with an impression gel. Sometimes the position of your uterus, your baby, and the shape of your belly can make it hard to find your heartbeat.
If you’ve been waiting to hear the familiar steady “lub-dub” sound of an adult heartbeat, you’re in for a surprise. Many women describe the sound of their baby’s heartbeat as like a galloping horse. This is because your baby’s heart beats much faster than yours, averaging between 110 and 160 beats per minute. (The typical resting heart rate for adults is 60 to 100 beats per minute.)
Around 20 weeks of pregnancy, you can listen to your baby’s heartbeat with a stethoscope.
How can you help your baby’s heart before and during pregnancy?
It’s worth doing everything you can to stay healthy before and during your pregnancy. But that is no guarantee that something will go wrong. Some things, like some congenital heart defects, are largely out of your control. Some congenital heart defects may be related to a maternal disease, such as diabetes. In other cases, heart problems may run in families.
Some special things you can do:
- Avoid cigarette smoking and passive smoking.Several studies have shown a strong association between cigarette smoke and congenital heart (and other) defects.
- Be careful with drugs. If you are taking systemic medications, talk to your health care provider before trying to get pregnant. Certain medications increase the risk of heart defects, including ACE inhibitors, the acne medication isotretinoin, lithium (a psychiatric drug), and warfarin (a blood thinner). You and your doctor may decide together that managing your underlying health problems with this particular drug is worth the small risk of a fetal heart defect. However, safer alternatives often exist, so explore your options with your doctor.
- Manage any chronic health conditions. For example, if you had diabetes before conception, take steps to control your blood sugar level before and during pregnancy. Uncontrolled diabetes before pregnancy is one of the leading causes of congenital heart defects.
- Don’t drink alcohol. Studies have shown that alcohol exposure during pregnancy is significantly linked to heart defects. There is no known reliable measure of alcohol during pregnancy.
- If needed, get your rubella vaccine before you get pregnant. When you see your doctor for a pre-pregnancy visit, you can check to see if you’re still immune to your childhood MMR vaccine. Sometimes immunity is lowered and women benefit from MMR boosting before pregnancy. (You should not be vaccinated during pregnancy). Getting rubella during pregnancy can affect the development of your baby’s heart.
- Tell your doctor if you have a family history of congenital heart problems.Special ultrasounds may be ordered to monitor the development of your baby’s heart.
