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Week 9: Baby is now officially a fetus — not an embryo.

Expert tip

Consider genetic screening tests (NIPT, nuchal translucency scan) — typically offered between weeks 10–13.

Baby's development this week

  • Embryo becomes a fetus at 9 weeks
  • Tiny muscles allow movement — not yet felt
  • External genitalia beginning to form
  • Eyelids fused shut to protect developing eyes
Science fact

The transition from embryo to fetus at 9 weeks is not just semantic — the placenta takes over hormone production from the corpus luteum, which is why nausea often begins to ease after week 10.

Your symptoms this week

Nausea peaks this week for most women then begins to ease
Try ginger tea, crackers before getting up, or vitamin B6 (10mg 3x/day). Small meals every 2 hours help.
Acne flares
hormonal surges affect sebaceous glands
Increased urination
uterus pressing on bladder before it rises into abdomen

Changes in your body

  • Uterus is the size of a tennis ball
  • Breast tissue expanding — may need new bras
  • Some women start showing a small bump
  • Blood volume increasing by up to 50% total through pregnancy
Mental health this week

First trimester fatigue is neurologically protective — your body is literally rerouting energy to fetal brain development.

Nutrition focus

  • Iron needs: 27mg/day in pregnancy (vs 18mg non-pregnant) — lentils have 6.6mg per cup
  • Avoid liver (too much vitamin A), raw eggs, and deli meats
  • Prunes (3/day) effectively treat pregnancy constipation — evidence-based
Appointment / test

NIPT (Non-Invasive Prenatal Test) blood draw can be done from 10 weeks — screens for chromosomal conditions with 99% accuracy.

This week's checklist

Ask doctor about NIPT screening at 10 weeks if interested
Avoid sleeping flat on your back — start left-side sleeping habit now
Book dental checkup — gum disease risk doubles in pregnancy

Track your pregnancy week by week

Interactive guide · 40 weeks · Fruit size visualizations · Personalized tips

Explore Week 9 in the Interactive Guide →