At five months of pregnancy (roughly 20 weeks), a fetus is about the size of a small banana, measuring around 6 to 7 inches from head to rump and weighing close to 10 ounces. It looks unmistakably human at this point, with defined facial features, working limbs, and skin covered in a fine layer of hair and a waxy protective coating.
Size and Proportions
By the midpoint of pregnancy, the fetus’s head is still relatively large compared to the rest of the body, but the limbs have caught up significantly from earlier months. The legs and arms are now proportional enough to move freely, and the body has a lean, slender look because fat deposits haven’t built up yet. Without that insulating layer of fat, the skin appears thin and somewhat translucent, with blood vessels visible beneath the surface. The fetus looks red or pinkish because of this transparency.
Skin, Hair, and Protective Layers
Two distinctive features define the skin at five months. The first is lanugo, a soft, fine hair that develops between 16 and 20 weeks. Lanugo covers most of the body and serves a practical purpose: it helps a waxy, cheese-like substance called vernix caseosa stick to the skin. Vernix acts as a barrier between the fetus and the surrounding amniotic fluid, which would otherwise irritate and damage delicate skin over months of constant exposure. Together, lanugo and vernix also help insulate the body and regulate temperature until enough body fat develops later in pregnancy to take over that job.
The skin itself is wrinkled and loose at this stage, draped over a frame that hasn’t filled out yet. It will thicken and smooth out gradually over the remaining months as fat accumulates underneath.
Facial Features
The face at five months has recognizable structure. The nose, lips, and ears are well formed and positioned. Eyebrows and some hair on the scalp are starting to become visible around 20 weeks after conception, though they’re still very fine. The eyelids are fully formed but remain fused shut. They won’t open for roughly another two months, but the eyes behind them are developing quickly. By 21 weeks after conception, the fetus begins making rapid eye movements behind those closed lids.
Toenails have been developing since around week 17, and fingernails are visible as well. Around 21 weeks after conception, ridges begin forming on the palms of the hands and soles of the feet. These ridges are the foundation for fingerprints and footprints, patterns that are already unique to this individual.
What You’d See on Ultrasound
Five months is when most people have their mid-pregnancy anatomy scan, typically scheduled around 20 weeks. This is often the most detailed ultrasound of the entire pregnancy, and it gives a clear picture of what the fetus looks like from the outside and inside. The sonographer examines the bones, heart, brain, spinal cord, face, kidneys, and abdomen. They also check the placenta and blood flow in the uterus.
On the screen, you can usually see the fetus moving, stretching, and even sucking its thumb. The profile view of the face is often surprisingly detailed, showing the slope of the nose, the curve of the lips, and the shape of the forehead. If the fetus cooperates by positioning itself well, the biological sex is typically visible at this scan, as the external genitalia are developed enough to distinguish.
Movement You Can Feel
At five months, the fetus is active. It can kick, stretch, roll, and flex its developing muscles. Most pregnant people begin feeling movement between 16 and 24 weeks, though first-time mothers often don’t notice it until after 20 weeks. Early movements typically feel like a gentle swirling or fluttering, sometimes described as bubbles or a light tapping. As the weeks progress, those sensations become more distinct kicks and jerky movements that are harder to miss.
The fetus isn’t moving constantly. It cycles between periods of activity and rest, though its sleep-wake patterns are still irregular and don’t yet follow a predictable schedule.
What’s Happening Inside
Internally, the organs are maturing rapidly at five months. The digestive system is active in a limited way: the fetus swallows amniotic fluid, which passes through the intestines. The water portion gets absorbed, and the remaining debris, a sticky, tar-like substance called meconium, lines the large intestine. This builds up throughout the rest of pregnancy and becomes the baby’s first bowel movement after birth.
The ears have developed enough that the fetus can begin hearing some sounds around 20 weeks. The amniotic fluid and surrounding tissue muffle most noise, so what reaches the fetus is limited primarily to low-frequency sounds: the rhythm of the mother’s heartbeat, the rush of blood flow, the low tones of voices nearby. This filtered sound environment actually plays a role in how the auditory system wires itself during development.
The heart is fully formed and pumping blood through a growing circulatory system. It beats fast, typically between 120 and 160 beats per minute, and is clearly audible on a Doppler device at prenatal appointments. The brain is in a period of rapid growth, developing the complex network of connections that will continue expanding well after birth.
How It Compares to Earlier Months
The difference between a five-month fetus and what it looked like just weeks earlier is dramatic. At three months, the fetus was about the size of a lime, with a head that made up nearly half its total length and limbs that were still stubby. By four months, it had grown to roughly the size of an avocado and began looking more proportional, but the skin was still paper-thin and features were less defined.
At five months, the leap in detail is striking. The fetus has fingerprints forming, hair growing, functioning ears, and a face that can make expressions as the facial muscles develop. It responds to stimuli, moves with purpose, and is large enough that its activity is felt from the outside. It still has significant growing to do, typically tripling or quadrupling its weight before birth, but its overall form at this stage looks like a smaller, thinner version of a newborn.