At 10 weeks of pregnancy, most women have a transvaginal ultrasound, where a slim probe is inserted into the vagina to capture close-up images of the uterus. A transabdominal ultrasound (the kind on your belly) may also be used, and sometimes both are done in the same visit. The type depends on your body, the position of your uterus, and what your provider needs to see.
Transvaginal vs. Transabdominal at 10 Weeks
Transvaginal ultrasound is considered the preferred method for evaluating pregnancies in the first trimester. Because the probe sits closer to the uterus, it produces sharper, more detailed images than a transabdominal scan at this stage. In a study comparing both approaches in 120 patients, transvaginal ultrasound delivered better image clarity in 63% of cases and was superior for obtaining measurements in 43% of cases. The advantage was especially pronounced in pregnancies at or before 10 weeks, in women with a higher body weight, and in women whose uterus tilts backward (a retroverted uterus).
That said, transabdominal ultrasound isn’t off the table. Some clinics start with a transabdominal scan and switch to transvaginal only if the images aren’t clear enough. Others go straight to transvaginal at 10 weeks because they know the image quality will be better at this early stage. Neither approach is painful, though the transvaginal scan can feel mildly uncomfortable. It typically lasts 15 to 30 minutes.
How to Prepare for the Scan
If you’re less than 14 weeks pregnant, you’ll likely be asked to drink 28 to 32 ounces of water about an hour before your appointment and avoid using the bathroom beforehand. A full bladder pushes the uterus into a better position for imaging, which is especially helpful if the scan starts transabdominally. If your provider switches to a transvaginal scan partway through, you may be allowed to empty your bladder first, since that approach doesn’t require it.
What the Ultrasound Checks
A 10-week ultrasound has several goals, and confirming that the pregnancy is progressing normally is the main one. Your provider will look for a heartbeat, verify the pregnancy is located inside the uterus, and check whether you’re carrying one baby or more. Multiple pregnancies are identified by the presence of separate gestational sacs or a visible membrane between twins.
The scan is also used to date the pregnancy accurately. The key measurement at this stage is the crown-rump length (CRL), which is the distance from the top of the baby’s head to its bottom. At exactly 10 weeks, the CRL typically falls between about 24 and 41 millimeters, roughly the size of a strawberry. This measurement is the most accurate way to estimate gestational age during the first trimester, and it may adjust your due date if it differs from what was calculated based on your last period.
If the CRL reaches at least 7 millimeters and no heartbeat is detected, that can indicate a pregnancy loss. But at 10 weeks, the embryo is well past that threshold, so a heartbeat is expected and usually easy to spot.
What You Can See at 10 Weeks
Ten weeks marks the end of the embryonic period, and the baby now has a distinctly human appearance on the screen. You can often make out the head, body, and developing limbs. Fingers and toes are separating at this point, bone cells are beginning to replace softer cartilage, and the jawbone is forming. Tooth buds are developing inside the gums, though those obviously won’t be visible on the scan.
You may also see the baby moving. Small arm and leg movements are common at 10 weeks, even though you won’t feel them for several more weeks. The yolk sac, a small round structure that nourished the embryo early on, is often still visible next to the baby at this stage.
Why It’s Too Early for Some Screenings
If you’ve heard about the nuchal translucency (NT) scan, which measures a small pocket of fluid at the back of the baby’s neck to screen for chromosomal conditions like Down syndrome, 10 weeks is slightly too early. The NT measurement is only considered reliable between 11 and 14 weeks, when the CRL measures between 45 and 84 millimeters. At 10 weeks, the baby hasn’t quite reached that size range. If your provider notices anything unusual at the back of the neck during a 10-week scan, the standard recommendation is to repeat the measurement at the correct gestational window.
However, 10 weeks is early enough for a blood-based screening called noninvasive prenatal testing (NIPT), which analyzes fragments of the baby’s DNA circulating in your blood. NIPT can be performed starting at 10 weeks and screens for common chromosomal conditions with high accuracy. Some providers coordinate the timing so the NIPT blood draw and the 10-week ultrasound happen at the same visit, though this varies by practice.
Dating Scan vs. Later Anatomy Scan
The 10-week ultrasound is sometimes called a dating scan or viability scan. It’s a focused look at the basics: Is the baby alive, how far along are you, and are there any early concerns? It’s not the same as the detailed anatomy scan, which happens around 18 to 22 weeks and examines the baby’s organs, spine, brain, and other structures in depth. That later scan is almost always transabdominal because the baby is large enough to image clearly through the abdomen by then.
At 10 weeks, the baby’s organs are still forming and far too small to evaluate in detail, so don’t expect the same level of anatomical information you’ll get later. The scan’s value at this stage is in confirming a healthy, properly dated pregnancy and giving you that first clear look at your baby.