The scan is optional and not everyone will have it. You can discuss whether you want or need a dating scan with your doctor or midwife. If you choose to have a dating scan, it will most probably be your first scan. You will need to get a referral from your doctor or midwife for a dating scan. Most women can instead have their first scan at 11 to 13 weeks — this is usually called the week scan.
A dating scan is carried out by ultrasound. A sonographer, who is usually a radiographer or a midwife trained in ultrasound, will complete your scan. If the scan is after 10 weeks, ultrasound recordings are usually made through your abdomen. The sonographer will put gel on your abdomen and move a hand-held device called a transducer, back and forward over your skin.
In some situations, such as when the scan is completed before 10 weeks of gestation or you are overweight, you may also need a vaginal scan. Your sonographer will let you know if this is needed. For an abdominal dating ultrasound, you will need to have a full bladder.
You may be asked to drink some water and not go to the toilet beforehand because a full bladder helps to push your womb up to give a better picture.
For a vaginal scan, you can have an empty bladder. This will provide a fairly accurate estimate of how many weeks pregnant you are. But it is important to remember that only a few women go into labour on their due date, so it can be more helpful to think about the month in which you are expecting your baby, rather than the exact day.
Learn more here about the development and quality assurance of healthdirect content. In order to get a close enough view of your uterus and fetus, the dating ultrasound is done transvaginally. Most would say it feels less invasive than a gynecological exam that uses a speculum. To perform this ultrasound, your OBGYN or ultrasound tech will gently insert a narrow ultrasound wand just inside your vagina. The transvaginal ultrasound wand is also called a transducer.
It will be covered by a condom and lubricant. The wand will not reach your cervix and is safe for your baby. You may be asked to arrive at your first ultrasound with a full bladder.
Having a fuller bladder helps to put your uterus in a better position for the ultrasound. This ultrasound is also called nuchal translucency screening. This genetic screening ultrasound is optional. During this ultrasound, your doctor will look for indicators of chromosomal disorders. Chromosomal disorders mean that the baby received an extra chromosome at conception and could have moderate to extreme physical or mental challenges.
These disorders include:. Read more about carrier screening and prenatal genetic testing. This ultrasound will be an anatomical scan. At the same time, experts caution against unnecessary ultrasounds, pointing out that while there are no known negative effects to date, ultrasounds are a form of energy, and it's conceivable that they affect a developing baby.
This may be especially true during the first trimester, when the embryo or fetus is more vulnerable to external factors. Some centers often found in malls and private offices sell packages of 3D ultrasounds and 4D ultrasounds as keepsakes.
While it can be tempting to get realistic photos and videos of your baby in a non-medical setting, experts recommend against it. There's no guarantee that staff at these clinics are trained properly — or that the ultrasound operator will be qualified to help you if you have questions, or if your ultrasound reveals a problem.
If problems are suspected in your pregnancy, or there's something concerning in your ultrasound results, you may be referred for a more detailed ultrasound that will be interpreted by a radiologist or maternal-fetal medicine specialist MFM. In the unlikely event that your baby has a health problem, information from your ultrasound can help you and your provider determine how to give your baby the best outcome possible.
For example, serious heart rhythm problems can be treated with medication while a baby is still in the womb. Other abnormalities, such as a urinary tract blockage, can be treated with surgery even before birth. And knowing about any birth defects can help your provider deliver your baby safely and determine what care your baby will need right after birth. If your baby has a dire health problem, being informed allows you to consider all the options, whether that means making the difficult decision to terminate a pregnancy , intervene medically, or prepare for the birth of a baby who needs special care.
There are people who can help you navigate the results of a concerning ultrasound. A genetic counselor can help answer a lot of your questions and guide you through your decision-making process.
Many high-risk pregnancy providers can refer you to a social worker for guidance, too. Prenatal tests: An overview. BabyCenter's editorial team is committed to providing the most helpful and trustworthy pregnancy and parenting information in the world.
When creating and updating content, we rely on credible sources: respected health organizations, professional groups of doctors and other experts, and published studies in peer-reviewed journals.
We believe you should always know the source of the information you're seeing. Learn more about our editorial and medical review policies. Abramowicz JS. Ultrasound in reproductive medicine: Is it safe?
Transvaginal Probe: If you need an ultrasound early in pregnancy , it may be necessary to use a transvaginal probe a transducer placed in the vagina. The fetus is deep in the mother's pelvis in early pregnancy—and since sound waves don't pass through bone, a transvaginal ultrasound lets your technologist to view your uterus through the cervix. This method may also be used later in pregnancy to locate your placenta if it's over the cervix or to measure the length of the cervix.
A transvaginal ultrasound is done with a wand-shaped probe covered with a latex sheath like a condom. The doctor will apply some lubricant and gently insert the ultrasound into your vagina. She will move the device to form the picture she needs on the ultrasound screen. The procedure doesn't hurt, but you might find it uncomfortable in the same way you might find a pelvic exam uncomfortable.
Transabdominal Ultrasound: After the first few weeks, most doctors will do an ultrasound on the abdomen. After arriving at your appointment , the doctor will smear a clear gel on the skin.
The gel allows the transducer a handheld device that looks like a microphone to slide more easily over your belly, and it improves the transmission of sound waves into your body.
Some doctors warm the gel, but if not, you might get a chilly sensation from the cold gel on your skin. Next the doctor moves the transducer along your abdomen, applying some gentle pressure. The transducer transmits sound waves that create a picture of the baby inside. If you're ticklish, you might find yourself challenged during this procedure. Take a deep breath and try to relax! Some doctors perform the first ultrasound exam around 6 to 8 weeks of pregnancy , often during the first prenatal visit.
Others only recommend this exam if a woman has symptoms of a high-risk pregnancy—for example, bleeding, abdominal pain, or a history of miscarriage , birth defects , or pregnancy complications. During this time, your baby is very small and your uterus and fallopian tubes are closer to your birth canal than to your abdomen, so your OB-GYN might conduct the test transvaginally to get a clearer picture.
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