At 8 weeks pregnant, the embryo is roughly 15 to 20 millimeters long, about the size of a raspberry, and has already developed recognizable features like eyes, a nose, an upper lip, and the beginnings of fingers. Your body, meanwhile, probably looks the same to everyone else, but your uterus has already doubled in size and your clothes may feel tighter around the waist.
What the Embryo Looks Like
By week 8, the embryo has come a long way from the tiny cluster of cells it was just a few weeks earlier. The trunk and neck have started to straighten out, which means it’s losing the curled, C-shaped posture of earlier weeks. The leg buds have taken on a paddle-like shape, and fingers have begun to form, though toes are still behind. Small swellings that will become the outer ears are developing, and the eyes are now noticeable as dark spots on either side of the head. The upper lip and nose have formed, giving the face its first recognizably human profile.
Crown-rump length, which measures from the top of the head to the bottom of the torso, ranges from about 15 mm at the start of week 8 to about 20 mm by the end. That’s smaller than a coin. Despite this tiny size, the major organ systems are already taking shape. The heart has been beating since around week 6, and the brain and spinal cord continue developing from the neural tube that closed earlier. The foundations for bones, kidneys, lungs, and intestines are all in place.
What Your Body Looks Like
Most people won’t notice a visible bump at 8 weeks. Your uterus, normally about the size of your fist, has grown to roughly the size of a tennis ball or large grapefruit. It’s still sitting low in the pelvis, well below the belly button, so the growth isn’t visible from the outside. But you’ll likely notice your waistband getting snug, and pants that fit comfortably a month ago may already feel tight.
Bloating plays a role too. Rising progesterone slows digestion, which causes gas and abdominal puffiness that can make you look further along than you are. Some people notice their lower abdomen feels firmer than usual, even if the shape hasn’t changed much in the mirror.
How You’re Likely Feeling
Week 8 tends to be one of the more intense weeks for early pregnancy symptoms. Morning sickness, which typically begins between weeks 4 and 9, is often at or near its peak. Despite the name, nausea can hit at any time of day. Rising progesterone is also responsible for the deep fatigue many people experience in the first trimester, the kind where you feel exhausted despite a full night of sleep.
Breast tenderness and swelling are common as well. Hormonal changes make breast tissue more sensitive, sometimes noticeably so within the first few weeks. This usually eases as the body adjusts, but at week 8, it can still be significant. Other symptoms you might notice include frequent urination (the growing uterus is pressing on your bladder), heightened sense of smell, and food aversions that seemed to appear overnight.
What an 8-Week Ultrasound Shows
If you have an ultrasound at 8 weeks, it may be done transvaginally rather than on the abdomen, since the embryo is still so small. On the screen, you’ll see the gestational sac, which is the fluid-filled space surrounding the embryo. Inside it, there’s a smaller bubble-like structure called the yolk sac, which provides nutrients until the placenta takes over. The embryo itself appears as a small, bright shape called the fetal pole.
A heartbeat is often detectable at this stage, but not always. If the timing is slightly off, or if the embryo is positioned in a way that makes measurement difficult, your provider may ask you to come back in a week or two. This is common and doesn’t necessarily indicate a problem. The ultrasound also confirms that the pregnancy is located inside the uterus and helps establish a more accurate due date based on the embryo’s measurements.
Prenatal Testing at This Stage
Carrier screening, which checks whether you carry genes for certain inherited conditions, can be done as early as 6 to 10 weeks. These are blood tests that look at your DNA rather than the embryo’s, so they’re available earlier than most other genetic tests. Broader prenatal genetic screening and diagnostic testing typically begins after 10 weeks, so your provider may discuss options now but schedule them for a later visit.
At the 8-week appointment, expect basic blood work, blood pressure, and a medical history review. This visit is often the first real prenatal appointment, and it sets the baseline for the rest of your care.