The first trimester finish line
By the end of this month, all major organs have formed and will spend the rest of pregnancy maturing rather than appearing from scratch. Fingers and toes separate, tiny nails start growing, and external genitals begin to differentiate, though it's usually too early to tell on ultrasound. Many people find nausea and fatigue start easing around now as the first trimester wraps up, though the timing varies.
Baby this month: about 7.4 cm — crown to rump, close to the size of a plum · about 23 g
≈ 7.4 cm — about the size of a plum
Illustration enlarged for clarity — the amber marker shows true relative size
What's developing right now
Heart, liver, kidneys, and brain have all formed in basic structure and will now focus on growth and maturation.
Fully separated, with soft nail beds starting to form.
Begin to differentiate, though it's usually too early to determine on ultrasound.
Start hardening from soft cartilage, a process that continues well into childhood.
Early muscle movements begin, though they're far too small to be felt yet.
What your body is doing
- Nausea often begins to ease for many people around this point, though not for everyone.
- The uterus is now roughly the size of a grapefruit, though it usually isn't visible yet from the outside.
- Energy levels can start to improve as the first trimester ends.
- Some people notice a slight increase in appetite as nausea fades.
Eating for this month
As appetite starts to return for many people, this is a good month to rebuild a varied plate. Iron and protein needs begin edging up as blood volume increases, supporting the placenta and a body that's working harder. Doctors often check iron levels around now and will advise on supplements if needed.
Checkups commonly done this month
- A dating and viability scan, often combined with first-trimester screening — commonly done between weeks 11 and 13, schedules vary by country and doctor
- Blood tests as part of first-trimester combined screening for certain chromosomal conditions
- Blood pressure and weight checks at a routine prenatal visit
Warning signs and what to do
Heavy bleeding that soaks a pad soon after putting it on, passing tissue, or severe cramping or pelvic pain: go to an emergency department now
Lighter bleeding or spotting: contact your doctor, maternity unit or an early pregnancy unit today
A fever along with feeling unwell: contact your doctor or maternity unit today
Persistent vomiting with signs of dehydration, such as dark urine or dizziness: contact your doctor or maternity unit today
Questions people ask
Does the end of the first trimester mean the risk of pregnancy loss drops?
Yes, generally. Most pregnancy losses happen in the first trimester, so reaching around week 13 with a confirmed heartbeat is reassuring, and the likelihood of loss drops meaningfully from this point. It's not a guarantee, but it's one reason many people feel more comfortable sharing their news around now.
What does the scan this month look at?
The dating scan confirms how far along the pregnancy is, checks the heartbeat, and can be combined with first-trimester screening for certain chromosomal conditions. It is a health check, not a test of the baby's sex.
Sizes and milestones are typical ranges — every pregnancy runs on its own clock. Educational content; your prenatal care team's guidance always comes first.