Conception Calculator — Week 28 From Conception (Fetal Age)
You are 28 weeks from conception, which corresponds to 30 weeks of gestational age (LMP-based). This page focuses on true fetal age — how long the baby has actually been developing since fertilisation.
Conception Calculator
Enter your LMP. Fetal age = gestational age − 2 weeks.
Baby at week 28
At 28 weeks from conception (30w gestational): Eyes can open and close. REM sleep begins — dreams possible. Fat continues accumulating.
Mother's body — what changes
28 weeks post-conception, your body is: Anti-D immunoglobulin injection if Rh-negative. Sleep on side — never on back.
Nutrition & supplements
Add ~450 kcal/day. Increase iron and DHA — brain growth peaks now. Split meals into 5–6 small portions to control heartburn and stable glucose. Week 28 from conception (30 weeks gestational) needs targeted micronutrients — the developmental window differs from LMP-based advice.
Safe exercise
Reduce intensity but keep moving. Pelvic floor + squats prepare for labour. Avoid contact sports, ski, horse-riding and hot yoga. At 28 weeks from conception, low-impact activity supports placental blood flow without stressing the fresh implantation.
Doctor visit checklist — week 28
- ✓Anti-D injection if Rh-negative; repeat GTT if flagged earlier
- ✓Note: 28 weeks from conception = 30 weeks LMP — clinic dating uses LMP
- ✓Confirm dating with crown-rump length at 8–13 weeks (±5 days accuracy)
Warning signs — call your provider immediately
- ⚠Heavy bleeding (soaking a pad in an hour)
- ⚠Severe abdominal pain that does not ease
- ⚠Fever above 38°C / 100.4°F
- ⚠Regular contractions before 37 weeks (preterm labour)
- ⚠Reduced fetal movement — fewer than 10 kicks in 2 hours
- ⚠Sudden swelling of face/hands + severe headache (preeclampsia)
- ⚠Bright red bleeding (placental abruption or previa)
Week 28 — Frequently asked questions
How accurate is the Conception Calculator at week 28?
The calculator uses standard gestational-age arithmetic (LMP + 280 days for standard; egg retrieval + 266 days for IVF day-5). Ultrasound crown-rump length between weeks 8–13 is more accurate (±5 days) than LMP — adjust EDD accordingly if the scan differs by more than 7 days.
What size is my baby at week 28?
Approximately the size of a large eggplant — length 37.6 cm and weight 1005 g. These are median values from ACOG dating criteria and Mayo Clinic conception timeline references.
Which symptoms are normal in week 28?
Anti-D immunoglobulin injection if Rh-negative. Sleep on side — never on back. Every pregnancy is different — call your provider if anything on the warning-signs list appears.
Should I have an ultrasound at week 28?
Anti-D injection if Rh-negative; repeat GTT if flagged earlier. Routine scan windows are: dating (10–13w), anatomy (18–22w), growth (28–32w).
How much weight should I gain by week 28?
Approximately 8.7 kg cumulative if you started at a normal BMI (IOM guideline). Underweight mothers gain more; overweight mothers less.
28 weeks from conception is how many weeks pregnant?
28 weeks from conception = 30 weeks gestational (LMP-based). All clinical care uses LMP dating unless IVF or dating scan overrides.
Can I feel conception happening at week 28?
No — conception itself is not felt. Later pregnancy symptoms are hormone-driven, not conception-related.
Content aligned with ACOG dating criteria and Mayo Clinic conception timeline. Reviewed by Dr. Maria Rehman, MD (OB/GYN). This page is educational and does not replace personal medical advice — call your obstetrician for any concern.