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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.

Trimester 2 · Week 24 of 4060%
Baby size
ear of corn
Length
30 cm
Weight
600 g

Conception Calculator

Enter your LMP. Fetal age = gestational age − 2 weeks.

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

How accurate is the Conception Calculator at week 24?

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 24?

Approximately the size of a ear of corn — length 30 cm and weight 600 g. These are median values from ACOG dating criteria and Mayo Clinic conception timeline references.

Which symptoms are normal in week 24?

Fundus 5 cm above navel. Colostrum may leak from breasts. Foot swelling common. Every pregnancy is different — call your provider if anything on the warning-signs list appears.

Should I have an ultrasound at week 24?

Glucose challenge test (24–28 weeks) — gestational diabetes screen. Routine scan windows are: dating (10–13w), anatomy (18–22w), growth (28–32w).

How much weight should I gain by week 24?

Approximately 6.9 kg cumulative if you started at a normal BMI (IOM guideline). Underweight mothers gain more; overweight mothers less.

24 weeks from conception is how many weeks pregnant?

24 weeks from conception = 26 weeks gestational (LMP-based). All clinical care uses LMP dating unless IVF or dating scan overrides.

Can I feel conception happening at week 24?

No — conception itself is not felt. Later pregnancy symptoms are hormone-driven, not conception-related.

Medically reviewed

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.

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