At 10 weeks of pregnancy, the baby is about the size of a strawberry, measuring roughly 3.1 centimeters (just over an inch) from head to rump and weighing around 4 grams. Despite that tiny size, it already looks remarkably human. This is actually the week the developing baby officially transitions from being called an embryo to being called a fetus, a milestone that reflects just how much has taken shape.
Overall Shape and Proportions
The head is still disproportionately large compared to the rest of the body, making up close to half the total length. The torso has straightened out from its earlier curled, comma-like shape, and a recognizable neck now separates the head from the shoulders. The overall silhouette is starting to look less like a cluster of cells and more like a miniature person, though the head-to-body ratio won’t even out for several more weeks.
Face and Ears
Facial features are becoming distinct. The eyes are formed but still set wide apart on the sides of the head, covered by eyelids that are continuing to develop and will stay fused shut for months. A small nose, mouth, and jaw are visible in profile. The outer parts of the ears are forming, though they sit lower on the head than they will at birth. Over the coming weeks, they’ll migrate upward to their final position.
Arms, Legs, Fingers, and Toes
This is a big week for limbs. The arms, hands, fingers, feet, and toes are fully formed, with no remaining webbing between the digits. Tiny fingernails and toenails are just beginning to develop. The arms and legs can bend at the elbows and knees, and the baby has started making small, spontaneous movements, though you won’t feel any of that for a while. Most first-time mothers don’t notice movement until around 20 weeks, and even experienced mothers typically feel it no earlier than 16 weeks.
Bones and Teeth
The skeleton is in the process of transitioning from soft cartilage to actual bone. This hardening process, which began a few weeks earlier, is now reaching the vertebrae. The spine is becoming more defined as individual vertebrae begin to solidify. Tooth buds won’t form for another few weeks (closer to weeks 14 through 16), but the jawbone is already taking shape to accommodate them later.
What You’ll See on an Ultrasound
If you have a scan at 10 weeks, you’ll likely see a small, bright figure on the screen with a visible head, body, and limb buds. Don’t be surprised if it’s hard to make out the details on your own. The sonographer will point out what you’re looking at. A heartbeat is typically visible and may also be audible, especially with a transvaginal ultrasound, which provides a clearer image at this early stage. An abdominal ultrasound can sometimes pick up the heartbeat too, though the picture may be less detailed.
Seeing a strong heartbeat at this point is a reassuring sign of a healthy pregnancy. For many parents, this scan is the first time the pregnancy feels real.
Prenatal Screening at 10 Weeks
Ten weeks is also the earliest point at which non-invasive prenatal testing (NIPT) becomes available. This is a simple blood draw from your arm that screens for certain chromosomal conditions. It works by analyzing small fragments of the baby’s DNA that circulate in your bloodstream. Before 10 weeks, there isn’t enough of that DNA present for the test to be reliable. If your provider recommends NIPT, it can be done anytime from this point through the rest of pregnancy. This is also the blood test that can reveal the baby’s sex, if you want to know early.