6 Weeks Pregnant
first trimester · Month 2
34 Weeks to Go!
Baby is as long as a lentil
Key Takeaways
- Heart beating — often visible on ultrasound
- Neural tube closing; brain vesicles forming
- Arm/leg buds lengthening; digital rays (fingers/toes) appearing
6 Weeks Pregnant
Baby’s Development
Your embryo is now about 4 to 6 millimeters long — roughly the size of a lentil [1]. The heart is already beating, having looped into an S-shape as its chambers begin to form. At this stage, the heart rate ranges from 110 to 160 beats per minute, often visible as a flicker on a transvaginal ultrasound [2]. This is a critical window for development: the neural tube closes at both ends (the anterior and posterior neuropores), with this essential process wrapping up around day 28 after conception, which lands squarely in week 6. The brain is dividing into three vesicles — the forebrain (cerebrum), midbrain, and hindbrain (cerebellum and brainstem) — while the optic vesicles that will become the eyes and the otic vesicles that will become the ears begin to take shape. Your baby’s arm and leg buds are lengthening, and the first hints of fingers and toes are appearing as digital rays, still webbed for now. Lung buds branch off from the gut tube, the liver begins producing the first blood cells, and the intestines start to herniate into the umbilical cord — a normal, temporary process that resolves around week 12 [1].
Pregnancy Symptoms
For many, this is the week symptoms reach their peak. Nausea and vomiting are common, with 70 to 80 percent of women experiencing some degree of what’s misleadingly called “morning sickness” — it can strike at any hour of the day. Extreme fatigue sets in as progesterone rises and your cardiac output increases by 30 to 50 percent. Your breasts may feel tender, heavy, and tingling, with veins becoming more visible and Montgomery’s tubercles more prominent. You’ll likely notice frequent urination, along with bloating, gas, constipation, and mood swings. Mild cramping and food aversions (often to meat, coffee, or eggs) are common too. Light spotting occurs in about 15 to 25 percent of pregnancies and is often benign — caused by implantation or cervical irritation — but you should always report it to your provider [2].
Body Changes
Your uterus has grown to about the size of a plum, and your cervix is softening and taking on a bluish tint. Your blood volume is beginning its climb toward a 40 to 50 percent increase by term, and your cardiac output is rising to match. Renal plasma flow increases by about 50 percent, which means more urine and more bathroom trips. Progesterone relaxes your smooth muscles, slowing digestion and opening the door to heartburn and constipation. Your breasts may grow by one to two cup sizes by the end of the first trimester, though you won’t have a visible belly just yet [2].
Tips for Week 6
- Schedule your dating ultrasound for weeks 7 to 8, which confirms viability, dates your pregnancy, checks the number of embryos, and rules out an ectopic pregnancy [1].
- Build a nausea toolkit: keep crackers by your bed and eat before rising, aim for six to eight small meals with protein and complex carbs each time, and try cold foods since they carry less scent. Ginger, vitamin B6, and Unisom can help per your provider’s guidance. If you can’t keep fluids down for 24 hours, call your provider — hyperemesis is a real risk [3].
- Start Kegels now — three sets of 10 each day. Your pelvic floor supports your uterus, bladder, and bowels, and strengthening it now helps prevent incontinence later.
- Document your questions for your first OB visit — write them down as they come to you so you arrive prepared with data.
Things To Do (Checklist)
- Schedule/attend dating ultrasound (weeks 7-8)
- Continue nausea toolkit; call provider if 24 hrs no fluids
- Start daily Kegels (3 sets × 10)
- Write questions for first prenatal visit
- Continue prenatal vitamin; add DHA if not included
Frequently Asked Questions
Q: I’m spotting. Is it a miscarriage? A: Not necessarily. Fifteen to 25 percent of women spot in the first trimester, and about half go on to have healthy pregnancies. Call your provider — they’ll check your hCG trend and possibly order an ultrasound. Heavy bleeding combined with cramping raises more concern [2].
Q: My nausea is all day, not just morning. A: “Morning sickness” is a misnomer. Nausea without vomiting is common, but if you’re vomiting three or more times a day or losing more than 5 percent of your body weight, call your provider [3].
Q: Is it safe to sleep on my back? A: At 6 weeks, back-sleeping is still fine because your uterus sits within your pelvis. The concern about back-sleeping begins around week 20, when the uterus can compress the vena cava [2].
For Dads
- Be the “designated driver” for food runs — she’ll need specific things at specific times, and questioning the request helps no one. Just go.
- Handle all the cleaning products — fumes from bleach, ammonia, and oven cleaner can trigger her nausea. Switch to vinegar and baking soda, or take on those chores yourself.
- Attend the dating ultrasound — seeing the heartbeat flicker on the screen makes it real in a way nothing else can. Take a photo or video of the screen if the office allows it.
- Set up a shared note app (Apple Notes, Google Keep) for questions, symptoms, and to-dos — keeping everything in one place reduces the mental load for both of you.
- Pray for continued healthy heart development — the heart is the first functioning organ, a small but profound milestone.
Sources
- ACOG — How Your Fetus Grows During Pregnancy
- Mayo Clinic — 6 Weeks Pregnant
- Expecting Better — Emily Oster (Chapter 4: First Trimester)
Sources
- guideline ACOG — How Your Fetus Grows During Pregnancy
- medical Mayo Clinic — 6 Weeks Pregnant
- book Expecting Better — Emily Oster
Your Checklist
Loading…
Unlock your vault (Journal tab) to track checklist progress.
Action Plan Items for Week 6
Loading…
Unlock your vault to track action plan status.