How often do you have ultrasound during pregnancy

Ultrasounds During Pregnancy: How Many and How Often?

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Ultrasounds are a regular part of prenatal medical care for most pregnant women, and also provide parents with their first glimpses of their developing baby. Although these photographs make for nice keepsakes, most women need very few scans, and medical guidelines firmly state that ultrasounds during pregnancy should be performed only when there is a valid medical indication.

According to the American Congress of Obstetricians and Gynecologists, there have been no reports of documented negative effects on the fetus from diagnostic ultrasound procedures. But, the ACOG discourages the use of ultrasounds for nonmedical purposes because while there are no confirmed biological effects caused by scans, there's always a possibility that some could be identified in the future.

"2D ultrasounds are the safest radiological modality offered to pregnant women, but as with everything, should be used in moderation," says Monica Mendiola, MD, a practicing physician in Women's Health at Beth Israel Deaconess HealthCare-Chelsea and an instructor in Obstetrics & Gynecology at Harvard Medical School.

Most healthy women receive two ultrasound scans during pregnancy.

"The first is, ideally, in the first trimester to confirm the due date, and the second is at 18-22 weeks to confirm normal anatomy and the sex of the baby," explains Mendiola. "As long as these ultrasounds are normal and mom's abdomen measures consistent with her gestation, then that is all most women need."

Mendiola notes that if there are any problems with these initial ultrasounds, or if there is a discrepancy in the fetus size along the way, a repeat ultrasound is warranted.

"Additionally, if moms have medical issues such as diabetes or hypertension, then they will also receive additional scans," she says.

Above content provided by Beth Israel Deaconess Medical Center. For advice about your medical care, consult your doctor.

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How Many Ultrasounds During Pregnancy Are Normal and What They're for

A healthy pregnancy typically requires two ultrasounds: one around 11 to 14 weeks and the other at about 18 to 20 weeks.
If any abnormalities or complications are detected during either of the routine ultrasounds, you might need more.
In high-risk pregnancies — usually due to the weight, age, or medical history — weekly ultrasounds may be recommended during the final month of pregnancy.
This article was reviewed by Olivia P. Myrick, MD, who is a clinical assistant professor with the Department of Obstetrics and Gynecology at NYU Langone.
Visit Insider's Health Reference library for more advice.

Ultrasounds are standard for every pregnancy because they're an effective way for doctors to monitor the health of both the growing fetus and mother-to-be.

In general, a healthy pregnancy should involve two ultrasounds: one in the first trimester and another mid-way through the second trimester.

However, each pregnancy is different and you may require more ultrasounds based on factors including age, weight, and medical history.

Here's what you need to know about when to get an ultrasound, what to expect during your appointment, and why you might need more than the standard two ultrasounds.

Ultrasound basics

True to its name, an ultrasound works by sending and detecting sound waves. An OB-GYN or an ultrasound technician uses a device called a transducer to send sound waves through the skin into the womb. The sound waves bounce off the fetus to create an image of the baby in the womb.

While getting ultrasound pictures is considered an early milestone for many parents, the primary purpose of an ultrasound is not for a keepsake. Doctors use this time to check on the baby's development, detect any genetic abnormalities, and examine the uterus, placenta, and amniotic fluid.

Generally speaking, ultrasounds are safe to perform during pregnancy, but in terms of how many to plan for, it's important to talk to your doctor to establish clear medical reasons as to why an ultrasound is needed.

"An ultrasound does not involve radiation, and, at the frequencies used for diagnostic imaging, poses no known risk to the mother or developing baby," says Dr. Stephen Chasen, director of obstetric imaging at NewYork-Presbyterian and Weill Cornell Medicine.

If you have a healthy pregnancy, you'll typically only need two ultrasounds. The first one is usually scheduled for late in the first trimester, around the 11 to 14-week mark. If the pregnancy has no major complications, the second ultrasound comes at about 18 to 20 weeks.

What to expect from the first trimester ultrasound

Many women experience their first ultrasound between 11 to 14 weeks into their pregnancy. With this examination, also known as a "dating ultrasound," the doctor will evaluate gestational age and rule out or identify any major abnormalities in early development.

During this early ultrasound, you can expect the doctor to:

Confirm the pregnancy: This is done by checking the fetal heartbeat.
Establish a due date: By measuring the fetus, doctors are able to confirm the gestational age — or how far along the pregnancy is — and establish an estimated due date.
Detect the number of babies: If there is more than one fetus, the doctor should be able to see it.
Check for ectopic pregnancy: A doctor can evaluate if the pregnancy is developing where it's supposed to. An ectopic pregnancy is when a fertilized egg attaches outside the uterus.
Screen for genetic orders: This exam typically includes a nuchal translucency screening, which is used to rule out Down Syndrome and physical defects of the heart like congenital heart disease.

What to expect from the second trimester ultrasound

The second ultrasound comes around 18 to 20 weeks. Also known as the "anatomy scan," the second trimester ultrasound is administered to check on the growth of the baby's vital organs and the position of the placenta. And yes, for those of you eager to start planning or choosing names, "fetal genitalia can also be imaged," says Chasen.

During the second ultrasound, you can expect the doctor to:

Examine the fetal anatomy: At this point, a doctor can detect any abnormalities in structures like the spine, heart, kidneys, brain, face, and limbs.
Check the biological sex: If you don't want to know the biological sex of the baby, be sure to let your health care provider know beforehand.
The position of the placenta: A low-lying placenta, or placenta previa is when a woman's placenta covers the cervix and can block the fetus's path through the birth canal during labor. In this case, your obstetrician will suggest at least one additional ultrasound to see if the placenta reorients and clears the way. If it doesn't, a cesarean delivery is required.

Additional ultrasounds may be needed

While two standard ultrasounds are considered routine, there are many reasons why an expecting parent may need more.

Some patients may have their first ultrasound prior to 11 weeks. The start of an intrauterine pregnancy is visible around 6 weeks, so an ultrasound that occurs any time after six weeks is generally reliable for determining how far along a patient may be. If you have an early ultrasound, you still will need an ultrasound at the 11 to 14 week period to properly assess development.

If any abnormalities or complications are detected during either of the routine ultrasounds, such as the position of the placenta, you might need more, says Chasen.

You may also need additional ultrasounds if your baby's at risk of birth defects or is extremely under or overweight by the time you reach term. The following can increase your baby's risk:

If you smoke or drink alcohol while pregnant, or have a family history of birth defects, it can increase your baby's risk of birth defects.
If you have asthma, inadequate weight gain during pregnancy, or high blood pressure, it can increase your baby's risk of being underweight.
If you're overweight or develop gestational diabetes during pregnancy, it can increase your baby's risk of being overweight come delivery time.

In high-risk populations — usually due to weight, age, or medical problems — weekly ultrasounds may be recommended during the final month of pregnancy. For these patients, these quick ultrasounds are used to assess amniotic fluid and fetal movement to make sure all is well with the pregnancy.

How much does an ultrasound cost?

An ultrasound may cost several hundred to over one thousand dollars, but you usually should not have to pay the entire bill.

Normally, your health insurance will cover most, or all of, the cost of an ultrasound if it deems the scan to be medically necessary. However, depending on your insurance plan, you may have to pay for the scan as part of your deductible.

The cost also depends on where you get an ultrasound and in what region. For example, an ultrasound at a hospital could run over $1,000. Whereas you can visit your local Planned Parenthood health center for low-cost ultrasounds whether you have health insurance, or not.

And an ultrasound in central Ohio can be as high as $1,205 while the max cost in NYC is $2,315. That's according to the free online tool HealthcareBluebook, which collects prices from large health plans nationwide. You can look up cost estimates for your specific area on HealthcareBluebook.com.

Insider's takeaway

While most women can expect at least two ultrasounds during pregnancy — in their first and second trimesters respectively — there are many reasons why your doctor may advise for more.

Ultrasound exams are important when monitoring the development of your baby, and it's normal to feel anxiety with the idea of needing more screenings beyond the routine checkups. Be sure to ask your healthcare provider questions, as well as for resources pertaining to any unforeseen issues that may arise.

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Jennifer Larson

Jennifer Larson is a freelance writer for Insider.

When to do the first ultrasound during pregnancy - "happy days" for screening of the 1st trimester

The world of a modern woman is always full of important events, meetings and an endless series of pre-planned things. When pregnancy occurs, many planned events can be moved from “expected” to “impossible” or simply postponed indefinitely. It is quite difficult to worry in advance and reschedule an important event at the most appropriate time, because planning events against the backdrop of pregnancy is a very difficult science. nine0003

Therefore, when pregnancy occurs, it is advisable to draw up at least an approximate “life plan for 9 months”. For example, it is known that maternity leave is most often preceded by unspent regular leave, and registration for pregnancy is preceded by the fact that a pregnancy has occurred and is developing normally.

Many events will now depend on how the new life develops. So, when a multiple pregnancy is diagnosed, not only the estimated due date will change, but maternity leave will come 14 days earlier, and the beginning of unspent leave will move with it. Therefore, one of the first steps in the event of a desired pregnancy is the passage of an ultrasound examination (ultrasound). Scientific and technological progress is rapidly changing the whole world, including the state of the prenatal ultrasound diagnostic service. Opportunities are changing, and with them the timing of the passage of research, which I would like to dwell on in more detail. nine0003

When to do an ultrasound scan during pregnancy

In 2012, the regulation “Decree of the Health Committee of the Government of St. Petersburg No. 39-r”1 came into force in St. Petersburg. Based on the above document, for a full-fledged ultrasound screening, it is desirable to undergo a study in “... the first trimester: 11 + 0-13 + 6 weeks; 18+0-20+6 weeks; and 32+0-34+6 weeks of pregnancy. ” However, these terms apply only to uncomplicated singleton pregnancies. At the same time, early registration is limited to up to 12 weeks of pregnancy with the ensuing consequences (payment of a lump-sum allowance to women registered in medical institutions in the early stages of pregnancy, clause 2-c of Decree of the Government of the Russian Federation of October 15, 2001 N 727 (as amended on 04.09.2012).

Therefore, at 11 weeks, a pregnant woman can be registered when establishing the fact of a developing pregnancy , for which ultrasound "... in the first trimester" is recommended. Most doctors recommend doing it at terms 7-8 weeks of pregnancy , because it is at this time that the heartbeat of a developing embryo is always determined as a sign of the physiological development of pregnancy.

The next obligatory steps in the ultrasound are screening. The entire pregnancy is divided into three periods (trimesters) and ultrasound plays an important role in each. nine0003

What is the diagnostic window for ultrasound during pregnancy

The first screening study is carried out from 11 weeks 0 days of pregnancy to 13 weeks 6 days of pregnancy. These limits are adopted for the timely detection of pathological conditions that determine the prognosis for the health of the fetus. Theoretically, any pregnant woman can apply for an ultrasound both at the beginning of the eleventh and at the end of the thirteenth week - the entire period is screening. However, among doctors who have dedicated their lives to prenatal ultrasound diagnostics, there is an opinion about the most preferable period in each screening period - the so-called " diagnostic window" or "happy days" .

Terms of fetal ultrasound examination

Legally regulated period (order KZ SPb No. 39-r dated 02/01/12)	Optimal timing/happy days
-	7-8
11 weeks 0 days – 13 weeks 6 days	12 weeks 2 days - 12 weeks 4 days
18 weeks 0 days – 20 weeks 6 days	20 weeks 0 days - 20 weeks 6 days
32 weeks 0 days – 34 weeks 6 days	32 weeks 0 days - 33 weeks 3 days

Diagnostic window in the 1st trimester of pregnancy

For the first screening study, these days include the interval from 12 weeks to 12 weeks. 2 days to 12 weeks 4 days . It is in this interval that the fetus has already grown enough to evaluate the smallest organs (eye lenses, heart), and the probability of ascertaining the most important morphological changes is significantly higher than at 11 weeks 0 days. On the other hand, each day lived by the baby increases not only the height and weight of the body, but the quality of the picture on the ultrasound machine.

According to various authors, the frequency of congenital pathology reaches 5%, and for patients in this group it is especially important to identify the problem at an early stage. In such special cases, it may be necessary to expand the range of diagnostic procedures, including prenatal karyotyping (obtaining samples of fetal tissue or amniotic structures in order to determine its karyotype). It takes time to carry out these procedures, from preparing the necessary tests for a pregnant woman, ending with directly invasive diagnostics and obtaining results about the health of the fetus. nine0003

In some cases, the established disease of the fetus raises the question of the impossibility of prolonging the pregnancy. According to the current legislation of the Russian Federation, the procedure of medical termination of pregnancy by the decision of the woman can be performed ". .. no later than the end of the twelfth week of pregnancy", but "... not earlier than 48 hours from the moment the woman applied to the medical organization for artificial termination of pregnancy" (clause 3.1, clause 3-b of article 56. Federal Law No. 323 of November 21, 2012)2. In other words, if a patient goes for an ultrasound scan at 12 weeks 5 days, if a serious pathology is detected, she is no longer sent for an artificial medical abortion, but for an abortion, which is a more complex and traumatic procedure. Therefore, when asked about the best rock for the first screening, almost any practitioner will answer: "up to 12 weeks 4 days" .

Diagnostic window in the 2nd trimester of pregnancy

The second screening period occurs at 18 weeks. 0 days and ends at 20 weeks 6 days pregnant . "Lucky days" is considered the entire twentieth week: 20 weeks. 0 days - 20 weeks 6 days . Not all the subtleties of the architectonics of the main organs can be considered so successfully, especially in pregnant women with increased body weight at 18 weeks of pregnancy. If so-called "markers of chromosomal problems" are detected, it may be necessary to perform prenatal karyotyping (obtaining fetal blood or amniotic fluid), which may take some time. nine0003

The collection of the material itself takes several minutes, but the preparation of the pregnant woman (examination, obtaining the results of blood and urine tests, etc.), transporting the material to the laboratory, examination and obtaining the results can take several days. If serious deviations in the state of health of the fetus are detected, in order to resolve the issue of further management tactics, the pregnant woman is sent to undergo a prenatal consultation consisting of an ultrasound doctor, a specialist in the field to which the identified disease belongs (for example, a surgeon, neurosurgeon, cardiologist, etc. ) . nine0003

Prior to the new regulation, the second screening period ranged from 18-22 weeks, even earlier than 18-24 weeks of pregnancy. According to WHO recommendations, the fetus becomes viable from the 22nd week of pregnancy, therefore, before this period it is very important to obtain all possible information about its condition and form a prognosis for health and later life. That is why now there is a restriction regulated by law, so that if serious problems with the health of the fetus are detected, all additional diagnostic procedures should be carried out in a timely manner and, if necessary, terminate the pregnancy without violating the Legislation of the Russian Federation2. nine0003

Diagnostic window in the 3rd trimester of pregnancy

The third screening period (32 weeks 0 days - 34 weeks 6 days of pregnancy) has two main objectives: the exclusion of congenital malformations with late manifestation and assessment of the fetal condition. Issuance of a referral for the passage of the third ultrasound along with maternity leave of 30 weeks. 0 days of pregnancy potentiates untimely early appeal of pregnant women for the third screening ultrasound before the period of 32 weeks 0 days, which in turn may require a second planned ultrasound in the "scheduled time". A later turnout (after 34 weeks) reduces the quality of the ultrasound picture obtained by changing the relationship between the amount of amniotic fluid and the volume of the fetal body towards the latter. Therefore " happy days" the third trimester can be considered the period 32 weeks 0 days - 33 weeks 3 days of pregnancy .

Unscheduled ultrasound at any stage is required, as a rule, only in case of complicated pregnancy, therefore, it is prescribed only according to indications and is performed regardless of the gestational age.

Notes: 1 - Order of the Health Committee of the Government of St. Petersburg dated February 1, 2012 N 39-r "On measures to reduce hereditary and congenital diseases in children in St. Petersburg".
2- Article 56 "Artificial termination of pregnancy". Federal Law of the Russian Federation of November 21, 2011 N 323-FZ "On the basics of protecting the health of citizens in the Russian Federation", entered into force: November 22, 2011, published on November 23, 2011 in "RG" - Federal issue No. 5639

The effect of ultrasound on the fetus: is ultrasound harmful to the baby

Table of contents

How ultrasound works
Effect of ultrasound on the fetus
The effect of ultrasound on a woman
Conclusion

Ultrasound has been used in the diagnosis of pregnancy since the 1960s. During this time, this method constantly confirms its reliability and effectiveness in terms of monitoring the condition of the baby and identifying possible violations. At the same time, many expectant mothers naturally have a question - what is the effect of ultrasound on the fetus and is there a risk to his health from exposure to ultrasonic waves? nine0003

How ultrasound works

To understand whether there is a risk of ultrasound affecting the baby or the mother's body, you need to consider the very principle of ultrasound. Sonography (or echography) is based on the high penetrating power of ultrashort sound waves. Penetrating into various tissues of the human body, they change their characteristics. These changes are captured by a sensor that picks up the reflected signal and converts it into a visual image. To date, there are 3 types of ultrasound: nine0003

2D - displays a two-dimensional image;
3D - displays a 3-dimensional model of the object under study;
4D - Shows a 3D model in motion.

The latter method is the most informative, as it allows assessing not only the morphological features of the fetus (size, structure of the body and limbs, the width of the cervical-collar space, etc.), but also its motor activity, heart rate. Using it, the doctor can determine such life-threatening conditions for the child as hypoxia, breech presentation, etc. Ultrasound also allows you to assess the condition of the amniotic membranes and the uterus itself. nine0003

As part of the management of pregnancy in accordance with the order of the Ministry of Health of the Russian Federation “On approval of the Procedure for the provision of medical care in the profile “Obstetrics and Gynecology”), a planned ultrasound is performed 3 times:

1 screening - at 11-14 weeks;
2 screening - at 19-21 weeks;
3 screening - at 30-34 weeks.

Also, the doctor may prescribe additional unscheduled ultrasounds if there are certain indications - for example, for women at risk. nine0003

Effect of ultrasound on the fetus

Numerous medical studies have been devoted to the impact of ultrasonic waves on the condition of the fetus, designed to objectively assess the safety of this method. None of the scientific papers available today provide evidence in favor of the fact that ultrasound negatively affects the child.

However, it cannot be argued that ultrasound has no effect on the human body. High-frequency sound waves heat tissues, for 1 hour of continuous exposure their temperature can rise by 2-5ᵒС. Hyperthermia potentially has a teratogenic effect - that is, it is capable of causing fetal developmental disorders when certain factors are combined. nine0003

Ultrasound carries the greatest potential risk for the baby at an early stage of pregnancy, when embryonic cells are actively dividing, and the organs and systems of the unborn child are just beginning to form. During this period, prolonged exposure to ultrasound and heating of tissues can disrupt the process of this formation and provoke congenital anomalies of the fetus.

The FDA (US Federal Food and Drug Administration) guidelines indicate an upper allowable threshold for ultrasonic exposure of 720 mW/cm ² . In obstetric practice, ultrasound is used with a power of more than 2 times lower than this threshold of 310 mW/cm ² . In other words, when examined in licensed medical institutions, overheating of the fetus during ultrasound with long-term consequences for its body is excluded.

The effect of ultrasound on a woman

The mother's body is obviously more resistant to external influences than the fetus. However, intense or prolonged exposure to ultrasound in early pregnancy can provoke contractile activity of the uterine muscles, and this creates a risk of miscarriage. nine0003

At the same time, ultrasound used in diagnostics does not reach values at which such an outcome is likely. Therefore, for the body of the woman herself, diagnostic ultrasound in a licensed medical institution does not carry any risk.

Conclusion

Based on the data of available studies, it can be argued that it was not possible to trace the relationship between ultrasound and abnormalities in the development of the fetus. Evidence that sometimes appears in the media that ultrasound causes autism or other developmental problems is not confirmed by other researchers. nine0003

To completely eliminate the possible negative impact of ultrasound on the fetus, it is recommended:

undergo an examination in a medical institution that has a state license to provide obstetric and gynecological care;
to undergo examination only as prescribed by a doctor - if a woman is not at risk and she has no problems with bearing, 3 fetal screening ultrasounds are enough for her during the entire period of pregnancy.

All pregnant women undergo ultrasound, and in the entire world practice of using this method, not a single case has been registered that clearly indicates its danger.