What's happening with your baby at 15 weeks
At 15 weeks, your baby is about the size of an apple — roughly 10 cm from head to bottom (called crown-rump length) and around 70 grams. Bones are hardening from soft cartilage, and the skin is still thin enough that blood vessels can be seen through it.
Baby's legs are now longer than the arms, and joints like elbows and knees can bend. Movement is picking up — stretching, kicking, even hiccuping — though at this stage it's usually still too small and light for you to feel.
Taste buds are forming, and baby can make sucking and swallowing motions. The eyes are still fused shut, but baby can sense light through closed eyelids.
What does 15 weeks pregnant feel like?
Many people notice more energy this week as early first-trimester fatigue and nausea start to ease, though this varies a lot and some people still feel queasy. Round ligament pain — a quick pulling sensation on one or both sides of your lower belly — can start as the uterus grows.
Other common symptoms around 15 weeks: nasal congestion, bleeding gums, increased appetite, and skin changes like a faint dark line (linea nigra) starting to appear down the belly.
Your bump may be barely noticeable or more visible depending on your body and whether you've been pregnant before. Both are normal at this stage.
Is 15 weeks when genetic screening tests happen?
Yes — the quad screen (or a similar second-trimester blood test) is typically offered between 15 and 20 weeks, and 15 weeks is often the earliest point it's available. It measures four substances in your blood to estimate the chance of certain chromosomal conditions and neural tube defects.
This is a screening test, not a diagnostic one. It gives you a probability, not a yes-or-no answer, and a higher-chance result doesn't mean something is definitely wrong.
If you want more definitive information, amniocentesis is usually available from around 15 weeks onward. Your midwife or doctor can talk through the options, what each test can and can't tell you, and whether they make sense for you.
What to do this week
If you're interested in second-trimester screening, ask your provider about timing this week — the quad screen has a window and it's worth booking early. Keep taking your prenatal vitamin, particularly for folic acid and iron.
If round ligament pain is bothering you, gentle stretching and changing position slowly can help. This is also a reasonable week to start practicing side-sleeping, since it becomes more comfortable and more recommended as pregnancy goes on.
If you've been waiting to share your news, many people feel more comfortable doing so around now, once early-pregnancy screening results are in or being processed.
When to call your provider
Call the same day for vaginal bleeding, severe or persistent abdominal pain, fever, a severe headache with vision changes, or fluid leaking from the vagina. These symptoms deserve a prompt check regardless of how mild they seem.
Light spotting after sex or an internal exam can happen, but it's still worth mentioning to your provider rather than assuming it's nothing. When in doubt, it's always reasonable to call.