Ultrasound in pregnancy

  1. Ultrasound: Sonogram
  2. There are basically seven different ultrasound exams, but the basic process is the same:
  3. How is an ultrasound performed?
  4. When are ultrasounds performed?
  5. What does the ultrasound look for?
  6. What are the risks and side effects to the mother or baby?
  7. If an ultrasound is done at 6 to 7 weeks and a heartbeat is not detected, does that mean there is a problem?
  8. How accurate are ultrasounds in calculating gestational age?
  9. Why do some healthcare providers schedule ultrasounds differently?
  10. How accurate are ultrasounds in determining the conception date to determine paternity?
  11. When can an ultrasound determine the sex of the baby?
  12. Are ultrasounds a necessary part of prenatal care?
  13. What You Need to Know About the Prenatal Ultrasound
  14. How Many Ultrasounds Do You Need During Pregnancy?
  15. What Are Ultrasounds?
  16. How Many Ultrasounds Do You Get During Pregnancy?
  17. Early Pregnancy Ultrasound (6-8 Weeks)
  18. Dating Ultrasound (10-13 Weeks)
  19. Nuchal Translucency Ultrasound (14-20 Weeks)
  20. Anatomical Survey (18-20 Weeks)
  21. Third Trimester Ultrasounds
  22. Doppler Fetal Monitoring
  23. How Many Ultrasounds Are Safe?
  24. Ultrasound for fetal assessment in early pregnancy
  25. Ultrasound During Pregnancy
  26. Who an ultrasound during pregnancy is for
  27. When an ultrasound during pregnancy is done
  28. First trimester ultrasound
  29. Second trimester ultrasound
  30. Additional ultrasounds during pregnancy
  31. How an ultrasound during pregnancy is done
  32. The difference between sonogram and ultrasound
  33. Risks of ultrasounds during pregnancy
  34. Pregnancy and birth: Ultrasound scans in pregnancy
  35. Sources

Ultrasound: Sonogram

Ultrasound in pregnancy

An ultrasound exam is a procedure that uses high-frequency sound waves to scan a woman’s abdomen and pelvic cavity, creating a picture (sonogram) of the baby and placenta. Although the terms ultrasound and sonogram are technically different, they are used interchangeably and refer to the same exam.

There are basically seven different ultrasound exams, but the basic process is the same:

Transvaginal Scans – Specially designed probe transducers are used inside the vagina to generate sonogram images. Most often used during the early stages of pregnancy.

Standard Ultrasound – Traditional ultrasound exam which uses a transducer over the abdomen to generate 2-D images of the developing fetus.

Advanced Ultrasound – This exam is similar to the standard ultrasound, but the exam targets a suspected problem and uses more sophisticated equipment.

Doppler Ultrasound – This imaging procedure measures slight changes in the frequency of the ultrasound waves as they bounce off moving objects, such as blood cells.

3-D Ultrasound – Uses specially designed probes and software to generate 3-D images of the developing fetus.

4-D or Dynamic 3-D Ultrasound – Uses specially designed scanners to look at the face and movements of the baby prior to delivery.

Fetal Echocardiography – Uses ultrasound waves to assess the baby’s heart anatomy and function. This is used to help assess suspected congenital heart defects.

How is an ultrasound performed?

The traditional procedure involves placing gel on your abdomen to work as a conductor for the sound waves. Your healthcare provider uses a transducer to produce sound waves into the uterus. The sound waves bounce off bones and tissue returning back to the transducer to generate black and white images of the fetus.

When are ultrasounds performed?

Ultrasounds may be performed at any point during pregnancy, and the results are seen immediately on a monitor during the procedure. Transvaginal scans may be used early in pregnancy to diagnose a potential ectopic or molar pregnancies.

There is not a recommended number of ultrasounds that should be performed during routine prenatal care. Because ultrasound should only be used when medically indicated, many healthy pregnancies will not require an ultrasound. The average number of ultrasounds varies with each healthcare provider.

Additional ultrasounds might be ordered separately if your healthcare provider suspects a complication or problem related to your pregnancy.

What does the ultrasound look for?

Ultrasounds are diagnostic procedures that detect or aid in the detection of abnormalities and conditions related to pregnancy. Ultrasounds are usually combined with other tests, such as triple tests, amniocentesis, or chorionic villus sampling, to validate a diagnosis.

An ultrasound exam may be performed throughout pregnancy for the following medically-necessary reasons:

First Trimester:

  • Confirm viable pregnancy
  • Confirm heartbeat
  • Measure the crown-rump length or gestational age
  • Confirm molar or ectopic pregnancies
  • Assess abnormal gestation

Second Trimester:

  • Diagnose fetal malformation
    • Weeks 13-14 for characteristics of potential Down syndrome
    • Weeks 18-20 for congenital malformations
  • Structural abnormalities
  • Confirm multiples pregnancy
  • Verify dates and growth
  • Confirm intrauterine death
  • Identify hydramnios or oligohydramnios – excessive or reduced levels of amniotic fluid
  • Evaluation of fetal well-being

Third Trimester:

  • Identify placental location
  • Confirm intrauterine death
  • Observe fetal presentation
  • Observe fetal movements
  • Identify uterine and pelvic abnormalities of the mother

What are the risks and side effects to the mother or baby?

The ultrasound is a noninvasive procedure which, when used properly, has not demonstrated fetal harm. The long-term effects of repeated ultrasound exposures on the fetus are not fully known. It is recommended that ultrasound only be used if medically indicated.

If an ultrasound is done at 6 to 7 weeks and a heartbeat is not detected, does that mean there is a problem?

No, it does not mean there is a problem. The heartbeat may not be detected for reasons that include: tipped uterus, larger abdomen, or inaccurate dating with last menstrual period. Heartbeats are best detected with transvaginal ultrasounds early in pregnancy.

Concern typically develops if there is no fetal heart activity in an embryo with a crown-rump length greater than 5mm. If you receive an ultrasound exam after week 6, your healthcare provider will begin to be concerned, if there is no gestational sac.

How accurate are ultrasounds in calculating gestational age?

Your healthcare provider will use hormone levels in your blood, the date of your last menstrual period and, in some cases, results from an ultrasound to generate an estimated gestational age. However, variations in each woman’s cycle and each pregnancy may hinder the accuracy of the gestational age calculation.

If your healthcare provider uses an ultrasound to get an estimated delivery date to base the timing of your prenatal care, the original estimated gestational age will not be changed.

Why do some healthcare providers schedule ultrasounds differently?

If there are any questions regarding gestational age, placenta location, or possible complications then more ultrasounds may be scheduled. Because ultrasound should only be used when medically indicated, many healthy pregnancies will not require an ultrasound. The average number of ultrasounds varies with each healthcare provider.

How accurate are ultrasounds in determining the conception date to determine paternity?

Your healthcare provider will use hormone levels in your blood, the date of your last menstrual period and, in some cases, results from an ultrasound to generate an expected date of conception. However, many differences in each woman’s cycle may hinder the accuracy of the conception date calculation.

The viability of sperm varies as well, which means intercourse three to five days prior to ovulation may result in conception. Ultrasound dating of conception is not reliable for determining paternity because the ultrasound can be off by at least 5-7 days in early pregnancy.

When can an ultrasound determine the sex of the baby?

You may have an ultrasound between 18 to 20 weeks to evaluate dates, a multiples pregnancy, placenta location or complications. It may also be possible to determine the gender of your baby during this ultrasound. Several factors, such as the stage of pregnancy and position of the fetus, will influence the accuracy of the gender prediction.

To be 100% sure you will have an anxious wait until birth!

Are ultrasounds a necessary part of prenatal care?

Ultrasounds are only necessary if there is a medical concern. As noted above, ultrasounds enable your healthcare provider to evaluate the baby’s well being as well as diagnose potential problems. For women with an uncomplicated pregnancy, an ultrasound is not a necessary part of prenatal care.

Compiled using information from the following sources:

1. William’s Obstetrics Twenty-Second Ed. Cunningham, F. Gary, et al, Ch. 16.

2. American Institute of Ultrasound in Medicine


Source: https://americanpregnancy.org/prenatal-testing/ultrasound/

What You Need to Know About the Prenatal Ultrasound

Ultrasound in pregnancy

A prenatal ultrasound test uses high-frequency sound waves, inaudible to the human ear, that are transmitted through the abdomen via a device called a transducer to look at the inside of the abdomen. With prenatal ultrasound, the echoes are recorded and transformed into video or photographic images of your baby.

The ultrasound can be used during pregnancy to show images of the baby, amniotic sac, placenta, and ovaries. Major anatomical abnormalities or birth defects may be visible on an ultrasound.

Most prenatal ultrasound procedures are performed topically, or on the surface of the skin, using a gel as a conductive medium to aid in the image quality. However, a transvaginal ultrasound is an alternative procedure in which a tubular probe is inserted into the vaginal canal.

This method of ultrasound produces an image quality that is greatly enhanced. It may be used early in pregnancy to get a clearer view of the uterus or ovaries if a problem is suspected. It can also be used to determine how far along you are in your pregnancy (gestational age).

Transvaginal ultrasound is also used to evaluate the cervix for problems such as shortening which may increase your risk of early labor.

All medical procedures have risk. But, there's no evidence to show a prenatal ultrasound done properly will harm a mother or her unborn child. Done properly means it's performed by a physician or a trained technician, called a sonographer. Ultrasound does not use radiation, as other procedures, such as X-rays, do.

An ultrasound is generally performed for all pregnant women around 20 weeks into her pregnancy. During this ultrasound, the doctor will confirm that the placenta is healthy and that your baby is growing properly in the uterus. The baby's heartbeat and movement of its body, arms and legs can also be seen on the ultrasound.

If you wish to know the gender of your baby, it can usually be determined by 20 weeks. Be sure to tell the health care provider performing the ultrasound whether or not you want to know the gender of your baby. Please note that ultrasound is not a foolproof method to determine your baby's gender; there is a chance that the ultrasound images can be misinterpreted.

An ultrasound may be performed earlier in your pregnancy to determine:

Later in pregnancy, ultrasound may be used to determine the:

  • Health of the baby
  • Placenta location
  • Amount of amniotic fluid around the baby
  • Position of the baby
  • Baby's expected weight

Newer ultrasounds are now available that show a three-dimensional view of the fetus. A moving picture interpretation is referred to as a 4-D ultrasound. This is similar in clarity to a photograph and can be useful in detecting birth defects when performed in a medical center.

Some facilities are providing this scan at the parents' request without a specific medical indication.

According to the March of Dimes, the FDA, and other experts, the use of these non-medical ultrasounds is discouraged, because untrained personnel may provide inaccurate or harmful information.

There is no special preparation for the ultrasound test. Some doctors require you to drink 4-6 glasses of water before the test, so your bladder is full. This will help the doctor view the baby better on the ultrasound. You will be asked to refrain from urinating until after the test.

Some doctors allow you to videotape the ultrasound so that you can take it home. Ask your doctor if this is an option. If it is, you will need to bring a blank videotape or DVD to your appointment.

You will lie on a padded examining table during the test and a small amount of water-soluble gel is applied to the skin over your abdomen. The gel does not harm your skin or stain your clothes.

A small device, called a transducer, is gently applied against the skin on your abdomen.

The transducer sends high-frequency sound waves into the body, which reflect off internal structures, including your baby.

The sound waves or echoes that reflect back are received by the transducer and transformed into a picture on a screen. These pictures can be printed out or sometimes recorded on a videotape.

There is virtually no discomfort during the test. If a full bladder is required for the test, you may feel some discomfort when the probe is applied over the bladder.

You may be asked to hold your breath briefly several times.

The ultrasound test takes about 30 minutes to complete.

The gel will be wiped off your skin and your health care provider will discuss the test results with you.

Insurance will pay for the ultrasound if it is deemed medically necessary. If you have an ultrasound that is not medically necessary (for example, to simply see the baby or find out the baby's sex), your insurance company may not pay for the ultrasound.

The March of Dimes.

© 2018 WebMD, LLC. All rights reserved.

Source: https://www.webmd.com/baby/ultrasound

How Many Ultrasounds Do You Need During Pregnancy?

Ultrasound in pregnancy

Pregnancy ultrasounds provide your doctor with plenty of valuable information.

The results allow him to monitor your baby's growth, detect abnormalities, predict your due date, determine whether you're carrying multiples, see the position of your placenta, and make out the sex of your baby.

But how many ultrasounds are safe during pregnancy, and when should you schedule the exams? We have the information you need to know.

What Are Ultrasounds?

During an ultrasound, your doctor or a skilled technician uses a plastic transducer to transmit high-frequency sound waves through your uterus. These sound waves send signals back to a machine that converts them into images of your baby. 

  • RELATED: Your Guide to Baby Ultrasound Exams

The test doesn't hurt, although gel (used to guide the transducer on the stomach) may feel cold and be messy. You should wear two-piece clothing to allow easy access to your tummy. 

Note that it will be hard to see much during the first few weeks of pregnancy, but a clearer photo will come around 13 weeks, which is the ideal time to share your exciting news.

How Many Ultrasounds Do You Get During Pregnancy?

Wondering how many times you’ll need to undergo an ultrasound? This varies the woman and her pregnancy. Here are some ultrasound exams you might have while expecting. 

Early Pregnancy Ultrasound (6-8 Weeks)

Your first ultrasound, also known as a sonogram, may take place when you're around 6 to 8 weeks pregnant. However, some doctors only conduct this exam if you have certain high-risk pregnancy conditions. These include bleeding, abdominal pain, and history of birth defects or miscarriage. 

  • RELATED: Ultrasound Pictures Throughout Pregnancy

This first exam may be conducted transgvaginally so doctors get a clearer picture of your baby. In this case, you OB-GYN will place a thin wand- transducer probe—which transmits high-frequency sound waves through your uterus—in your vagina. The sound waves bounce off the fetus and send signals back to a machine that converts these reflections into a black and white image of your baby.  

At 6 weeks' gestation, it's possible to see the baby's heartbeat. Your practitioner will also predict your baby’s due date, track milestones, determine the number of babies in the womb, and see whether you have an ectopic pregnancy.  

Dating Ultrasound (10-13 Weeks)

Those who forgo the 6-8 week ultrasound might have  a”dating ultrasound” around weeks 10-13. This gives parents the same type of information: due date, your baby’s “crown-rump length” (measurement from head to bottom), the number of babies in the womb, and fetal heartbeat. 

Nuchal Translucency Ultrasound (14-20 Weeks)

Between 14 and 20 weeks, you may also have a nuchal translucency (NT) test to check for Down syndrome and other chromosomal abnormalities, says Joanne Stone, M.D., a professor of obstetrics, gynecology, and reproductive Science at Mount Sinai School of Medicine in New York.

Women whose screening test revealed a potential problem, who are 35 or older, or who have a family history of certain birth defects should consider it.  Doctors will measure hormones and proteins with a blood test, and they'll also gauge the thickness at the back of the baby's neck with an ultrasound.

A thicker neck may indicate an increased risk for birth defects Down syndrome and trisomy 18.

  • RELATED: What to Expect at Your First Ultrasound

Anatomical Survey (18-20 Weeks)

This detailed ultrasound, generally between weeks 18 to 20 of pregnancy, lasts 20 to 45 minutes if you're having one baby and longer if you're having multiples. This is the most thorough checkup your baby will have before she is born. 

The doctor will check your baby's heart rate and look for abnormalities in her brain, heart, kidneys, and liver, says Jane Chueh, M.D., director of prenatal diagnosis and therapy at Lucile Children's Hospital Stanford, in Palo Alto, California.

She'll count your baby's fingers and toes, check for birth defects, examine the placenta, and measure the amniotic fluid level. And she'll probably be able to determine your baby’s sex, although it's not a slam dunk; an experienced tech gets it right more than 95 percent of the time.

(If you don't want to know your baby's sex, let her know ahead of time.) 

Third Trimester Ultrasounds

Many moms-to-be don't need an ultrasound in the third trimester.

But if your pregnancy is considered high-risk—for example, if you have high blood pressure, bleeding, low levels of amniotic fluid, preterm contractions, or are over age 35 —your doctor may perform in-office, low-resolution ultrasounds during your prenatal visits for reassurance, says Dr. Chueh. You'll also get a follow-up scan if your cervix was covered by the placenta at your 20-week scan.

Doppler Fetal Monitoring

This test is typically performed during the last trimester on women who suffer from gestational diabetes. A regular ultrasound uses sound waves to produce images; this one bounces high-frequency sound waves off circulating red blood cells to measure blood flow and blood pressure. The test will determine if Baby is getting enough blood.

  • RELATED: Gender Ultrasound: Are You Having a Boy or Girl?

How Many Ultrasounds Are Safe?

An ultrasound is considered safe for both you and your baby when it's used for medical purposes. Although ultrasounds require no radition, only a trained professional who can interpret the results with accuracy should perform them. Your technician should be schooled in obstetrical ultrasound, preferably at a center accredited by the American Institute of Ultrasound in Medicine. 

Some medical practices now offer 3D (high quality and life) and 4D (moving picture) ultrasounds, which may help doctors detect certain fetal abnormalities and birth defects.

However, these types of exams are also available at fetal portrait studios in places shopping malls. Experts discourage these “keepsake” ultrasounds since untrained personnel may give out inaccurate information, says Michele Hakakha, M.D.

, an OB-GYN in Beverly Hills and author of Expecting 411.

Plus, although ultrasounds are safe in medical settings, they might heat tissues or produce bubbles (cavitation) during use.

Experts aren’t sure about the long-term effects of heated tissues or cavitation when ultrasounds are conducted outside of a medical need with non-trained professionals.

“Therefore, ultrasound scans should be done only when there is a medical need, a prescription, and performed by appropriately-trained operators,” according to the FDA in a December 2014 statement

  • RELATED: Are Ultrasounds Safe for Babies?

Source: https://www.parents.com/pregnancy/stages/ultrasound/ultrasound-a-trimester-by-trimester-guide/

Ultrasound for fetal assessment in early pregnancy

Ultrasound in pregnancy

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Ultrasound During Pregnancy

Ultrasound in pregnancy

Ultrasounds have become a regular — and very welcome — part of prenatal care. Early in pregnancy, ultrasounds are used to confirm the fetal heartbeat and a uterine (as opposed to ectopic or tubular) pregnancy.

Later, ultrasounds screen for fetal growth, placenta location and umbilical cord, as well as the baby's general health and anatomy.

Ultrasounds can also be useful for checking the length of your cervix, if there is any suspicion that you may be in preterm labor.

Who an ultrasound during pregnancy is for

All pregnant women should receive more than one ultrasound during pregnancy.

When an ultrasound during pregnancy is done

Usually, a woman gets a minimum of two sonograms during her pregnancy, one in the first trimester and one in the second trimester.

First trimester ultrasound

In the first trimester of pregnancy, an early ultrasound is a routine part of prenatal care at 6 to 9 weeks, allowing parents a welcome first glance of their tiny baby bean. The American Congress of Obstetricians and Gynecologists (ACOG) recommends that all moms get a first trimester ultrasound. It's used to:

  • Confirm your estimated due date more accurately by measuring the fetus (after the first trimester, ultrasound measurements of the fetus are less accurate)
  • Confirm the fetal heartbeat.
  • Make sure the pregnancy is taking place where it's supposed to, in the uterus (and to rule out a tubular or ectopic pregnancy)
  • Determine the number of fetuses

While most practitioners wait until at least 6 weeks to perform the first ultrasound, a gestational sac can be seen as early as 4 1/2 weeks after your last period; a heartbeat can be detected as early as 5 to 6 weeks (though it might not be detected that early in all cases).

First Ultrasound In 3 Words

Second trimester ultrasound

Midway through your pregnancy, usually between week 18 and week 22, a detailed anatomy scan called a level 2 ultrasound is performed.

It's generally done by a trained sonographer in a hospital or specialized clinic, where the equipment is more sophisticated.

The second trimester ultrasound is not only fun for you to watch, it gives you and your practitioner a clear picture of the overall health of your baby and your pregnancy. It's a way to:

  • See how baby's developing and offer reassurance that everything is going exactly the way it should be, by measuring the size of your baby and checking all the major organs, measuring the level of amniotic fluid to make sure there's the right amount, and looking at the location of your placenta
  • Tell you your baby's sex, if you want to know
  • Give you a sneak peek at your baby (especially now that she looks a baby!) — ask the sonographer to point out your baby's hands, feet, face and tiny organs the stomach and kidneys

Routine second trimester ultrasounds are usually done in 2D; most practitioners reserve the more detailed 3D and 4D ultrasounds for only when medically necessary, to more closely examine a fetus for a suspected anomaly, since there are mixed opinions on the safety of the ultrasound technology.

Additional ultrasounds during pregnancy

Sometimes a mom-to-be will have additional ultrasounds over the course of her pregnancy if she's considered high-risk. If you have any spotting during pregnancy, your practitioner will usually perform an ultrasound to confirm that all is well. If you are carrying multiples, you will have frequent ultrasounds to monitor their growth.

You may receive an ultrasound to check for changes in the cervix (thinning, opening or shortening) if your doctor thinks you may be at risk of preterm labor.

Additionally, ultrasounds are a part of several other tests, including:

How an ultrasound during pregnancy is done

If you're getting an ultrasound before week 6 or 7, your practitioner will ly perform a transvaginal ultrasound. A small, long transducer (or wand) is wrapped in a condom- cover and sterile lubricant and inserted into the vagina. The practitioner will move the wand within the vaginal cavity to scan your uterus.

The transducer emits sound waves, which bounce off structures (otherwise known as your baby) to produce an image you can see on a computer or video screen. You'll be able to watch along with your practitioner (though you'll ly need help to understand what you're seeing).

You can probably even take home a small printout as a souvenir.

Later on, you'll get a transabdominal ultrasound examination, where a gel is rubbed onto your belly and then the wand is rubbed over your belly to produce images of your baby.

Ultrasounds can last from five to 30 minutes and are painless, except for the discomfort of the full bladder necessary for the first-trimester transabdominal exam. They can be somewhat uncomfortable if the sonographer needs to press hard on your abdomen to see a particular part of your baby more clearly.

The difference between sonogram and ultrasound

Though the words sonogram and ultrasound are often used interchangeably, there is a distinction. Ultrasound is the actual technology of using sound to produce sonogram pictures, including the one that you'll take home.

Risks of ultrasounds during pregnancy

Ultrasounds are noninvasive and very low-risk. That said, medical guidelines caution against unnecessary exposure.

Because no researcher would willingly put a fetus in harm's way in the name of science, it's difficult to study the long-term effects of ultrasound use — which means there is the possibility of unintended consequences with overuse.

What's more, though ultrasounds are usually relatively accurate at estimating a baby's size, they can under- or over-estimate weight, especially if they're overused, which may occasionally result in unnecessary C-sections or premature deliveries. 

That's why ACOG along with the Food and Drug Administration (FDA) urge practitioners and patients to only use ultrasounds if they're medically necessary. These groups also recommend that pregnant women avoid keepsake 3-D and 4-D sonograms during pregnancy advertised by private companies along with at-home fetal monitors. 

Some research has found that the average number of ultrasounds women are receiving is much higher — more than five over the course of pregnancy, on average. So if your doctor recommends more than two ultrasounds when you're expecting, ask questions to ensure that what you're receiving is medically required and in the best interests of the health of your baby.

Source: https://www.whattoexpect.com/pregnancy/pregnancy-health/prenatal-testing-ultrasound/

Pregnancy and birth: Ultrasound scans in pregnancy

Ultrasound in pregnancy

Created: August 16, 2012; Last Update: March 25, 2015; Next update: 2021.

Many pregnant women and their partners look forward to ultrasound scans. But getting that all-important first picture of your child is, of course, not the reason why pregnant women in Germany are offered ultrasound scans. Instead, the aim is to make sure that the pregnancy is progressing normally and the child is developing well.

In Germany, pregnant women with statutory health insurance are usually offered three standard ultrasound scans at no extra cost. They are sometimes also referred to as screening examinations.

The main purpose of these three standard ultrasound scans is to determine whether the pregnancy and the child's development are progressing normally. Generally speaking, 96 to 98 100 pregnant women give birth to a healthy child. But the ultrasound sometimes detects abnormalities that lead to further examinations – and maybe some difficult decisions as well.

Doctors are required to discuss the advantages and disadvantages of ultrasounds before carrying them out. Germany's Federal Joint Committee (G-BA) has published a detailed information booklet as a guide. Every pregnant woman has the right not to have one or all of the ultrasound scans without giving a reason. Deciding not to have a scan doesn’t affect your insurance coverage.

It’s best to talk with your doctor before the scan to discuss whether you want to see the ultrasound images and which results you want to know. If you don’t want to know the sex of your child or other things they might see, it’s important to make that clear beforehand.

In Germany, women with statutory insurance who are not considered to have a high-risk pregnancy are offered three standard ultrasound scans. These scans provide basic information about the progression of the pregnancy and the child's development.

During the scan, the gynecologist checks the location of the placenta and the amount of amniotic fluid. The child's size is measured and plotted on a graph in your maternity records. The results of the scan can help to prepare for the birth of the child.

If an ultrasound scan finds abnormalities or delivers unclear results, further examinations can be carried out to clarify them.

The first ultrasound serves mainly to confirm that you are pregnant. The doctor checks to see if the fertilized egg cell has lodged in the womb and developed into an embryo or fetus. The term embryo is used in the early stages of pregnancy, the term fetus after the 10th week.

The length of the baby and the diameter of the embryo’s head can already be measured during the first ultrasound. The results help to estimate how far pregnant you are and when the baby is expected. The doctor also listens for a heartbeat and checks for a multiple pregnancy.

Pregnant women have two choices for the second ultrasound:

  1. Standard ultrasound examination

  2. Extensive ultrasound examination

During the basic ultrasound scan, the child's head, belly and thigh bone are measured. The position of the placenta in the womb is also determined. If the placenta is too low, special measures might have to be taken during the rest of the pregnancy and childbirth.

The extensive ultrasound examines the following body parts more closely:

  • Head: Are the head and the cerebral ventricles (brain cavities) the right shape? Is the cerebellum visible?

  • Neck and back: Have they developed normally?

  • Chest: Are the heart and ribcage in proportion? Is the heart visible on the left-hand side? Is the heart beating rhythmically? Can the four chambers of the heart be identified?

  • Torso: Is the front abdominal wall closed? Are the stomach and bladder visible?

The extensive ultrasound may only be performed by gynecologists with a special qualification.

During the third ultrasound scan, the baby's head, belly and thigh bone are measured again. The baby's position and heartbeat are also checked.

If there are particular medical reasons, statutory health insurance will also cover additional ultrasound scans. Standard ultrasound does not include an ultrasound scan of the organs by specialist gynecologists. That can be a good idea if a pregnancy is considered higher risk or if other scans produced unclear results.

You can ask to have this kind of scan without a medical recommendation. In that case it counts as an individual health care service (in German: Individuelle Gesundheitsleistung, or IGeL for short), which you have to pay for yourself. All other ultrasound scans for which there is no specific medical reason also have to be paid for pocket.

Scans that look specially for signs of congenital abnormalities are subject to the German Genetic Diagnostics Act. One example is the nuchal translucency scan that uses ultrasound to look for signs of Down syndrome.

Before carrying out these kinds of scans, doctors are required to provide special information and genetic advice.

This not only means clarifying medical questions, but also any psychological and social concerns that may be relevant to the scan and the results.

Abnormalities of a genetic nature can also be detected during a standard ultrasound scan. Special support is then also offered.

Standard ultrasound scans can detect some developmental disorders in children straight away, while they can only find less conclusive signs of some other health problems or anomalies. There are some problems and developmental disorders than cannot be identified at all by ultrasound.

As with all examinations, ultrasound scans can produce false results. Two types of errors are possible:

  1. The ultrasound finds signs of developmental disorders even though the child is developing normally.

  2. The ultrasound results are normal even though the unborn child does have health problems or anomalies.

It is not possible to say exactly how often ultrasound scans in Germany deliver false results.

The frequency of errors depends on factors such as how much amniotic fluid is in the amniotic sac, the child's position and how thick the mother’s abdominal wall is.

The quality of the ultrasound device and the operator's expertise can also influence the result. According to international statistics, about 1 100 pregnant women can expect to receive a false result.

The sounds waves used in standard ultrasound scans are not known to be harmful to either mother or child. But ultrasound can be harmful if it finds unclear results or abnormalities.

This can make people feel anxious and worried and may also mean that more examinations are needed.

These additional examinations can be intensive and sometimes have serious effects that are difficult for the parents-to-be to cope with.

But the ultrasound scan can also give the impression that the unborn child is developing normally even though it does have health problems. The expectant parents falsely assume that their child is healthy. It can then be quite a shock if their child is born fully unexpectedly with serious health problems or anomalies.

Furthermore, not all scan results are clear and not all problems that are identified during an ultrasound examination can be treated. This can be unsettling, difficult to deal with and call for tough decisions to be made.

If there are signs that the unborn child might be physically or mentally disabled, the question of whether to abort or continue the pregnancy might arise. This can lead to inner conflict.

Some women say later that they wouldn't have had the scan if they had thought about the potential consequences beforehand.

Every woman has the right to opt having any of the ultrasound scans. Perhaps you only want to know if your child is developing at a normal rate, but not if there are any anomalies.

Or you decide against ultrasound scans completely because you do not want to be confronted with the associated uncertainties and potentially difficult decisions.

Deciding to continue your pregnancy in any case, regardless of how your child is developing, can also be a reason not to have ultrasound scans.

But opting ultrasound scans or not wanting particular information can have disadvantages.

It could mean that abnormalities in the unborn child remain undetected and untreated, even though treatment may have been possible in the womb. Possible risks for the mother, the placenta being too low, may go unnoticed.

Some scan results can also provide reasons for going to a specialist clinic or practice for the remainder of the pregnancy and for childbirth.

Maternity support centers are on hand to help you with any questions you might have about pregnancy and giving birth. Your right to support also includes pregnancy-related check-ups. This support is usually free of charge.

Many other advice centers can provide help with questions about pregnancy and childbirth. You can find their locations and more information (in German) on the website run by Germany’s Federal Centre for Health Education (BZgA) at www.familienplanung.de/schwangerschaft.


  • IQWiG health information is written with the aim of helpingpeople understand the advantages and disadvantages of the main treatment options and healthcare services.

    Because IQWiG is a German institute, some of the information provided here is specific to theGerman health care system. The suitability of any of the described options in an individualcase can be determined by talking to a doctor. We do not offer individual consultations.

    Our information is the results of good-quality studies. It is written by ateam ofhealth care professionals, scientists and editors, and reviewed by external experts. You canfind a detailed description of how our health information is produced and updated inour methods.

Source: https://www.ncbi.nlm.nih.gov/books/NBK343308/