How many times ultrasound in 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 basicsTrue 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 ultrasoundMany 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.
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.
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 takeawayWhile 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.
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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.
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.
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.
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.
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.
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. ) .
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.
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
▶Ultrasound during pregnancy✅ ADONIS Medical Center in Kyiv
Ultrasound (ultrasound) during pregnancy is the gold standard for diagnosis. It is included in the program of mandatory prenatal screening, which is carried out in the first, second and third trimester. Ultrasound provides accurate information about the course of pregnancy and the development of the fetus. This is one of the most informative studies, which is desirable to be carried out on high-quality equipment and by an experienced specialist.
When to have an ultrasound during pregnancy
According to the state pregnancy protocols, a planned ultrasound is done:
- At 12-14 weeks;
- At 20-24 weeks;
- 32-34 weeks.
The obstetrician-gynecologist who monitors the pregnancy determines the exact timing of when to do an ultrasound scan. If there are indications, he may prescribe unscheduled studies.
During the first prenatal screening, an ultrasound checks that the pregnancy is proceeding normally, determines the duration of the pregnancy, and excludes chromosomal abnormalities and malformations in the fetus. At this time, Down syndrome, Edwards and Patau are detected, as well as pathologies that are incompatible with life and lead to disability.
At 12-14 weeks of gestation, the specialist assesses such parameters of the fetus as:
- The thickness of the collar space, which should normally be 1.6-1.7 mm. Its increase indicates the risk of chromosomal pathologies;
- The distance of the fetus from the crown to the coccyx, which is normally 43-65 mm. Shorter length is considered a sign of genetic pathologies or delayed development;
- Nasal bones, to be between 2 and 4. 2 mm in length;
- Fetal heart rate and strength;
The second ultrasound, which is done at 20-24 weeks, examines the anatomy of the fetus. At this time, all organs and systems should already be formed in him. In addition, they study how the pregnancy itself proceeds, whether there is placental abruption, shortening of the cervix, or another disorder that carries the risk of abortion or premature birth.
At 20-24 weeks of pregnancy check:
- Fruit size;
- Sex of fetus;
- Location and development of all internal organs and systems;
- Fetal heart rate and strength;
- Condition of the placenta and amniotic fluid;
- Uterine muscle tone and other indicators.
Many couples wonder when the sex of the baby can be seen on the ultrasound? As a rule, it is determined precisely at the second planned study. However, you can find out the sex earlier, starting at 16 weeks.
The last scheduled ultrasound allows you to assess the size of the fetus, its motor activity and position in the uterus. Also, for a period of 32-34 weeks, a Doppler study of the blood flow of the mother and child is carried out. During studies, indications for early induction of labor or caesarean section may be identified, in particular entanglement of the umbilical cord of the fetus, breech presentation, oligohydramnios, or placental abruption.
At 32-34 weeks during ultrasound check:
- Condition of the child's spine and internal organs;
- Fetal heart rate and strength;
- Head and body size;
- Approximate weight;
- Condition of the umbilical cord, placenta, amniotic fluid and cervix.
It is quite common for women to have more than 3 ultrasounds. For example, the ADONIS pregnancy management program provides for a minimum of 5-6 ultrasounds, which are performed at different times.
A woman can also have an ultrasound at any time of her choice to find out the sex of the baby or to make sure that the pregnancy is proceeding normally, but the main thing is not to do this too often.
Is it harmful to have an ultrasound during pregnancy
Most OB/GYNs believe that it is not harmful to have an ultrasound during pregnancy. However, to date, there is not a single scientific study that would confirm the safety or, conversely, the harmful effects of ultrasound on the development of a child.
At the same time, it is still advised to conduct a study only according to indications. The International Society for Ultrasound in Obstetrics and Gynecology recommends adhering to the ALARA principle, that is, minimizing the degree of exposure and the time of ultrasound to minimize possible risks.
Accuracy of diagnosis
Prenatal ultrasound shows only the likelihood of developing a pathology in the fetus, therefore, additional examinations are always carried out to clarify the diagnosis.