At 14 weeks, a fetus is about the size of a lemon, measuring roughly 86 millimeters (3.4 inches) from crown to rump. It has a distinctly human appearance, with a proportionally large head, visible facial features, and limbs that are growing longer and more defined. This is the start of the second trimester, and the fetus has moved well past the embryonic stage into a period of rapid growth and refinement.
Size and Proportions
The head still makes up a large portion of the body, but the rest is catching up. The neck has lengthened enough that the head is now upright rather than curled against the chest. Arms and legs are longer and more proportional, though the legs still lag behind the arms in development. The body is slim and lean, with very little fat underneath the skin.
Facial Features
The face looks increasingly human at this stage. The eyes, which started on the sides of the head, have migrated closer to the front, though the eyelids are fused shut and will stay that way for several more months. The ears are close to reaching their final position on the sides of the head. A small nose bridge is forming, and the mouth and lips are well defined. The fetus can make facial expressions, including squinting and frowning, as the facial muscles develop and the brain begins sending signals to them.
Skin and Body Surface
The skin at 14 weeks is extremely thin and nearly translucent. Blood vessels are visible beneath the surface. The fine, downy hair called lanugo hasn’t appeared yet (it typically develops between 16 and 20 weeks), so the skin is still smooth. Later, lanugo will coat the body in a layer of soft, feathery fuzz that helps protect the skin from the amniotic fluid.
What the Fetus Can Do
A 14-week fetus is surprisingly active, though most pregnant people won’t feel movement for several more weeks. The fetus can stretch, turn, kick, and curl its fingers and toes. Basic sucking and swallowing reflexes are developing, and the fetus is already swallowing small amounts of amniotic fluid. This swallowing isn’t just practice: it plays a role in regulating amniotic fluid levels in the uterus.
Internal Development
The kidneys are fully functional by this point, having started producing urine around 10 weeks. By 14 weeks, fetal urine is a major contributor to the volume of amniotic fluid, with the lungs producing roughly one-third. The kidneys will continue developing new filtering units all the way until birth, but the basic plumbing is working.
The skeletal system is transitioning from soft cartilage to harder bone. Ossification, the process of cartilage hardening into bone, is underway in the long bones of the arms and legs, the ribs, and parts of the skull. The nasal bone is typically visible on ultrasound by this stage, and its presence is sometimes evaluated during screening for chromosomal conditions.
Reproductive Organs and Sex
External genitalia are forming, and in many cases a skilled ultrasound technician can identify the sex. Accuracy improves significantly after 14 weeks. One study found that predictions made after 14 weeks were correct 100% of the time, compared to only about 54% accuracy at 11 weeks. That said, the baby’s position during the scan matters a lot. If the fetus isn’t angled cooperatively, even an experienced technician may not be able to get a clear view.
What You Might Notice
At 14 weeks, the uterus has filled the pelvis and is starting to rise into the lower abdomen. Some people notice a small, firm bump forming just above the pubic bone. This is also the stage when early pregnancy symptoms like nausea and fatigue often start to ease, though that varies widely from person to person. You won’t feel the fetus move yet. Most people notice the first flutters between 16 and 22 weeks, with first-time pregnancies tending toward the later end of that range.
What It Looks Like on Ultrasound
On a 14-week ultrasound, you can see the head, body, and all four limbs clearly. The profile view often shows the forehead, nose, and chin in silhouette. You may be able to watch the fetus move in real time, opening and closing its hands or shifting position. The heartbeat is visible and audible, typically beating between 150 and 170 times per minute. Compared to a first-trimester scan, where the embryo looked more like a small blob with a flickering heartbeat, a 14-week ultrasound shows something that looks unmistakably like a baby.