Second trimester · Pregnancy week by week
Week 17 of pregnancy
Baby is the size of a pomegranate. About 5.10 inches, 140g.
By week 17, the fetus has individual fingerprints. The 20-week anatomy scan is the most important imaging study of pregnancy; Black women have lower utilization rates of detailed anatomy scans per ACOG data. Source
What's happening with the baby
The fetus has formed unique fingerprints. The body grows faster than the head now. Fat begins to deposit. The fetus practices breathing motions. The placenta is fully developed.
What's happening for you
Bump growth accelerates. Many women begin feeling fetal kicks regularly. Lower back pain may start. Breasts may begin producing colostrum (clear or yellow fluid). Round-ligament pain continues.
Common (normal) symptoms this week
More distinct fetal movements, lower back pain, occasional cramping, growing bump, breast colostrum (small amounts), increased vaginal discharge, mild swelling of feet.
Call your OB or 911 if
- Severe abdominal or one-sided pelvic pain with bleeding — possible ectopic pregnancy.
- Heavy vaginal bleeding (soaking a pad in an hour) with cramping.
- Fainting, severe dizziness, or shoulder-tip pain — ectopic with internal bleeding is an emergency.
- Fever over 101°F with chills or pelvic pain.
- Severe vomiting that prevents keeping any fluids down for 24+ hours (hyperemesis).
Why this week matters for Black families
The second trimester is when the standard prenatal-care path diverges most sharply by demographic. The 20-week anatomy scan, the preeclampsia-prevention conversation, and the gestational-diabetes screening all happen here. Black women have higher rates of gestational diabetes, fibroids that complicate pregnancy, and a documented risk of missed preeclampsia diagnoses because early symptoms (headache, swelling, vision changes) are dismissed more often (per Bryant 2010 Obstet Gynecol PMID 20567176). If you have any of these symptoms, name them and ask explicitly: 'Has preeclampsia been ruled out?'
What to do this week
Confirm the 20-week anatomy scan is scheduled (and is a detailed scan, not a quick one). Ask: 'Will the cardiac, brain, and spine be examined in detail?' Begin researching cord blood banking decisions. Continue prenatal vitamins, aspirin if prescribed, and exercise.
Pregnancy / baby
Babylist
Universal baby registry across every store, with curated lists vetted by parents. Includes a Black-owned brands collection.
Start a registryAffiliate link — we may earn a commission at no extra cost to you.
References
- ACOG Practice Bulletin 226 — Anatomic Survey.
- SMFM Consult Series #57 — Anatomy Survey Protocols.
Last medically reviewed: .
Free tools
Track your due date + check benefits eligibility
Estimate your due date, see your trimester at a glance, and check Medicaid + WIC eligibility for your state.