7 Weeks Pregnant

Baby’s Development

Your embryo is now about 8 to 13 millimeters long — roughly the size of a blueberry [1]. This is the embryonic period, the most rapid phase of organ formation in your entire pregnancy. All major organs have begun forming: the heart (now with four chambers), brain, lungs, liver, kidneys, and intestines. The heart rate peaks around 150 to 170 beats per minute, and the brain’s hemispheres are visible on ultrasound. Eyelids are forming (they’ll stay fused shut for a while), along with the tongue and lips, while nostrils appear as small depressions. The inner ear structures are complete. Your baby’s arm and leg buds now flex at the elbows and knees, with digital rays becoming more defined. Bones are beginning to ossify, transforming from cartilage into bone. The intestines are still herniated into the umbilical cord, and the liver is producing red blood cells — a job it will keep until the bone marrow takes over [2].

Body Changes

Your uterus has grown to about the size of a lemon, though it’s still tucked within your pelvis. You may not notice much weight gain yet, and that’s perfectly normal. Visible veins may appear as blue lines on your breasts and “milk lines” down your torso — a sign that your blood supply is ramping up. Your nipples and areolae may darken and itch, and the linea nigra (the line down your belly) may begin to show, more visible in darker-skinned women. You might even notice changes in your hair’s texture [2].

Tips for Week 7

• Attend your dating ultrasound between weeks 7 and 8 — the crown-rump length (CRL) is the most accurate dating method, accurate to within about five days. It confirms viability, whether you’re carrying one or two babies, and the pregnancy’s location [1].
• Keep your nausea toolkit at full strength: vitamin B6 (25 mg three times a day) plus Unisom (25 mg at night), small frequent meals, ginger, and acupressure wristbands. If you’ve gained fewer than 5 pounds total and aren’t vomiting, you’re on track [3].
• Stay active — fatigue may tempt you to rest constantly, but mild exercise like walking, swimming, or prenatal yoga actually reduces fatigue and mood swings.
• Begin interviewing OBs or midwives if you haven’t chosen one yet. Good questions to ask: their intervention philosophy, hospital affiliation, experience with high-risk factors (ovarian cyst, IVF, age 35+), and their on-call model.

Things To Do (Checklist)

• Attend dating ultrasound; confirm CRL
• Continue nausea toolkit; call OB if can’t keep fluids
• If not done: choose OB/midwife + practice affiliation
• Gentle daily exercise: 20-30 min, stay cool
• Plan first “official” announcement (after week 12?)

Frequently Asked Questions

Q: When does the nausea end? A: About 90 percent of women find it resolves by weeks 14 to 16, though some have it through week 20 or beyond. Hyperemesis gravidarum (severe nausea and vomiting) is rarer, affecting 0.3 to 2 percent, and requires medical treatment [3].

Q: Is the fetal heart rate too fast? A: 150 to 170 bpm is normal this week. A faster rate is common; a slow rate below 100 bpm by week 7 raises more concern. Discuss trends rather than a single reading [2].

Q: Can I have sex? A: Yes, in low-risk pregnancies. Light spotting afterward is common due to cervical friability. Avoid sex if you have bleeding, pain, or preterm labor risk [1].

Sources

1. ACOG — How Your Fetus Grows During Pregnancy
2. Mayo Clinic — 7 Weeks Pregnant
3. What to Expect When You’re Expecting — Heidi Murkoff (Chapter 4: First Trimester)