Conception Calculator — Week 24 From Conception (Fetal Age)
You are 24 weeks from conception, which corresponds to 26 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.
How to Use This Calculator
1. Enter the LMP date
Use the labelled fields and units that match your situation.
2. Calculate instantly
The result, visual comparison, and working update as values change.
3. Discuss the estimate with your clinician
Check assumptions, then copy, print, or share the calculation.
Practical Examples & Use Cases
| Starting date | Method | Calculation | Planning use |
|---|---|---|---|
| 1 Jan | LMP | +280 days | Estimated due date |
| Known clinical date | Ultrasound | Clinician dating | Confirm or revise estimate |
Baby at week 24
At 24 weeks from conception (26w gestational): Viability threshold — with NICU support, survival possible if born now. Inner ear fully developed — sense of balance.
Mother's body — what changes
24 weeks post-conception, your body is: Fundus 5 cm above navel. Colostrum may leak from breasts. Foot swelling common.
Nutrition & supplements
Add ~340 kcal/day above pre-pregnancy baseline. Prioritise iron (27 mg/day), calcium (1000 mg), omega-3 DHA (200–300 mg) and 71 g protein. Continue prenatal vitamin. Week 24 from conception (26 weeks gestational) needs targeted micronutrients — the developmental window differs from LMP-based advice.
Safe exercise
Continue 150 min/week. Avoid supine (flat-on-back) exercises after week 20 — they compress the vena cava. Swimming and prenatal Pilates are ideal now. At 24 weeks from conception, low-impact activity supports placental blood flow without stressing the fresh implantation.
Doctor visit checklist — week 24
- ✓Glucose challenge test (24–28 weeks) — gestational diabetes screen
- ✓Note: 24 weeks from conception = 26 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
- ⚠Sudden gush of fluid (early rupture of membranes)
- ⚠Absent fetal movement for 12+ hours after 24 weeks
- ⚠Severe headache + visual disturbance (preeclampsia)
Week 24 — Frequently asked questions
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.
Related Calculators & Tools
Pregnancy Calculator
Week 24 guidance and calculation for this pregnancy timeline.
IVF Pregnancy Calculator
Week 24 guidance and calculation for this pregnancy timeline.
Twin Pregnancy Calculator
Week 24 guidance and calculation for this pregnancy timeline.
Pregnancy Countdown Calculator
Week 24 guidance and calculation for this pregnancy timeline.
Conception Calculator — Week 23
Review the previous week in this pregnancy timeline.
Conception Calculator — Week 25
Continue to the next week in this pregnancy timeline.