What's happening with your baby at 6 weeks
Your baby's heart — still just a simple tube at this point — starts to beat around week 6, usually somewhere between 100 and 120 beats per minute. It's too early to hear it with a regular stethoscope, but it can sometimes be seen on an early ultrasound as a small flicker.
The neural tube, which will become the brain and spinal cord, is closing this week. Tiny buds that will grow into arms and legs are just starting to appear, along with the early structures for eyes and ears.
Your baby is officially an embryo now, measuring somewhere around 4 to 6 millimeters — roughly the size of a sweet pea. There's still no recognizable face or limbs yet; that comes over the following few weeks.
What symptoms are normal at 6 weeks pregnant?
Nausea (with or without vomiting) often starts around 6 weeks, along with fatigue, tender or swollen breasts, and needing to pee more often. Some people also notice a heightened sense of smell, mild cramping, or mood swings — all driven by rapidly rising hormones.
Symptoms vary enormously from person to person. Some people feel nauseous by breakfast every day; others feel almost nothing at 6 weeks and that's just as normal.
Light spotting or mild cramping can happen as your uterus grows and stretches. Heavier bleeding or pain that feels severe is different — that's covered below.
Will you have an ultrasound at 6 weeks?
Some providers offer an early dating ultrasound between 6 and 9 weeks, especially if you have a history of pregnancy loss, fertility treatment, or uncertain dates — but many wait until closer to 8 to 12 weeks. Either approach is normal; it depends on your provider's routine practice and your individual history.
If you do have a scan this early, it may show a gestational sac, a small fetal pole, and sometimes a flickering heartbeat. If the heartbeat isn't visible yet, that alone doesn't mean anything is wrong at this stage — dates can be off by a week or more, and a follow-up scan is usually recommended.
What to do this week
Keep taking your prenatal vitamin with folic acid, and try to stay hydrated even if nausea is making food unappealing. Small, frequent meals — crackers, toast, or anything bland — often sit better than large ones when nausea is at its worst.
If you haven't booked your first prenatal appointment yet, do it now; many practices schedule the first visit around 8 weeks. Avoid alcohol, smoking, and recreational drugs, and flag your pregnancy to your provider before starting or stopping any medication.
When to call your provider
Call the same day if you have heavy bleeding (soaking a pad an hour), severe abdominal pain, pain concentrated on one side, or fever. These can sometimes signal an ectopic pregnancy or other complication that needs prompt attention.
Also call if you're vomiting so often you can't keep any fluids down for 24 hours — that level of nausea, sometimes called hyperemesis gravidarum, is manageable but needs medical support.