Your Pregnancy Results

Estimated Due Date

Thursday, December 25, 2025

Only 4% of babies are born on their exact due date. Most are born within 2 weeks.

Calculate your pregnancy due date and get detailed information about your pregnancy journey. Our free calculator supports multiple calculation methods and provides week-by-week development information.

Key Dates & Milestones

Estimated Due Date December 25, 2025
Last Menstrual Period March 20, 2025
Conception Window Mar 29 - Apr 4, 2025
End of 1st Trimester June 12, 2025
End of 2nd Trimester September 18, 2025
Full Term (37 weeks) December 4, 2025

Your Current Progress

31 w 4 d

Weeks Pregnant

3

Trimester

78.9%

Pregnancy Progress

Week 31: Week 31: Five Senses Functioning

All five senses are now working. The baby can see dim shapes, distinguish between light and dark, track light sources, and taste flavors in amniotic fluid. Fingernails have reached the fingertips.

Baby Size: Coconut (306mm)

Common Symptoms: Shortness of breath, frequent urination, Braxton Hicks contractions, possible pelvic pressure

Recommended Medical Checkups

  • First Prenatal Visit: May 15, 2025 Week 8
  • First Ultrasound: May 15 - Jun 26, 2025 Weeks 8-14
  • Anatomy Scan: Jul 24 - Aug 21, 2025 Weeks 18-22
  • Glucose Screening: Sep 4 - Oct 2, 2025 Weeks 24-28

Important Note

This calculator provides estimates only. Your healthcare provider may adjust your due date based on ultrasound measurements and other factors. Always consult with your healthcare provider for personalized medical advice.

Trimester Information

The first trimester is a period of rapid development and major changes. During these crucial 12 weeks, your baby transforms from a fertilized egg to a recognizable human form with all major organs beginning to form.

What's Happening

  • The neural tube (brain and spinal cord) forms
  • Heart begins beating around week 6
  • Limb buds appear and develop into arms and legs
  • Major organs begin forming
  • Facial features start developing
  • By week 12, baby is about 2-3 inches long

Common Symptoms

  • Morning sickness (nausea and vomiting)
  • Fatigue and exhaustion
  • Breast tenderness
  • Frequent urination
  • Food aversions or cravings
  • Mood swings

Medical Care

Schedule your first prenatal visit between weeks 8-10. Your provider will confirm the pregnancy, perform initial screening tests, and establish your due date. An early ultrasound may be performed to verify gestational age and heartbeat.

Many consider the second trimester the most comfortable period of pregnancy. Morning sickness typically subsides, energy levels improve, and you're not yet dealing with the physical discomforts of late pregnancy.

What's Happening

  • Baby's movements become noticeable (quickening)
  • Sex can often be determined on ultrasound
  • Baby develops sleep/wake cycles
  • Hearing develops - baby can hear your voice
  • Fingerprints form
  • By week 26, baby is about 14 inches long and weighs 2 pounds

Common Symptoms

  • Growing belly becomes visible
  • Back pain and round ligament pain
  • Skin changes (darkening, stretch marks)
  • Increased appetite
  • Braxton Hicks contractions may begin
  • Nasal congestion

Medical Care

The anatomy scan (detailed ultrasound) occurs around week 20 to check baby's development. Glucose screening for gestational diabetes typically happens between weeks 24-28. Regular prenatal visits continue monthly.

The third trimester brings the final stages of development as your baby prepares for birth. You'll experience more physical discomforts but also the excitement of meeting your baby soon.

What's Happening

  • Baby gains significant weight
  • Lungs mature and prepare for breathing
  • Baby moves into head-down position
  • Brain continues rapid development
  • Baby practices breathing movements
  • By week 40, average baby is 19-21 inches and 6-9 pounds

Common Symptoms

  • Shortness of breath as baby crowds lungs
  • Frequent urination as baby presses on bladder
  • Heartburn and indigestion
  • Swelling in feet and ankles
  • Trouble sleeping
  • Braxton Hicks contractions increase

Medical Care

Prenatal visits increase to every 2 weeks starting at week 28, then weekly after week 36. Your provider will monitor baby's position, your blood pressure, and watch for signs of labor. Group B strep testing occurs around week 36.

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Learn More

  • Pregnancy - Wikipedia

    Comprehensive overview of pregnancy, gestational development, and prenatal care from conception through childbirth.

  • Prenatal Development - Wikipedia

    Detailed information about fetal development stages, from fertilization through the embryonic and fetal periods.

  • Obstetrics - Wikipedia

    Medical field focused on pregnancy, childbirth, and postpartum care, including prenatal testing and delivery methods.

Other Due Date Methods

LMP: January 1, 2025 LMP: March 15, 2025 LMP: June 1, 2025 LMP: September 1, 2025 Conception: February 14, 2025

Mathematical Explanation

<h3>Calculation Methods</h3> <p>The pregnancy due date calculator uses these established medical formulas:</p> <ul> <li> <strong>Naegele's Rule (LMP Method)</strong>: Due Date = LMP + 280 days + (Cycle Length - 28 days)<br> This method assumes ovulation occurs 14 days into your cycle. For non-standard cycles, the adjustment accounts for earlier or later ovulation. </li> <li> <strong>Conception Date Method</strong>: Due Date = Conception Date + 266 days<br> This calculation uses 38 weeks (266 days) from conception to birth, which is 2 weeks less than the gestational age method. </li> <li> <strong>Due Date Method</strong>: Works backwards from a known due date to calculate current pregnancy progress and key milestones. </li> </ul> <p><strong>Note</strong>: These calculations provide estimates. Only 4% of babies are born exactly on their due date. Ultrasound measurements may adjust your estimated due date.</p>

Frequently Asked Questions

Due date calculators provide estimates based on standard gestational periods. Only about 4% of babies are born on their exact due date. Most healthy pregnancies deliver within 2 weeks before or after the estimated date. Your healthcare provider may adjust your due date based on ultrasound measurements, especially early pregnancy scans which are the most accurate.

Gestational age is calculated from the first day of your last menstrual period and is the standard used in pregnancy. Fetal age (or conceptional age) is calculated from the actual date of conception and is about 2 weeks less than gestational age. Medical providers use gestational age because it's easier to determine accurately.

Yes, your due date may be adjusted based on ultrasound measurements, particularly if performed in the first trimester when measurements are most accurate. An early ultrasound (before 13 weeks) can date a pregnancy within 3-5 days. If there's a significant discrepancy between your LMP date and ultrasound measurements, your provider may change your due date.

If you don't remember your last menstrual period, your healthcare provider will use an early ultrasound to determine gestational age and due date. The ultrasound measures the baby's size to estimate how far along you are. This is also common for those with irregular periods or who conceived while breastfeeding.

Yes, if your menstrual cycle is longer or shorter than the standard 28 days, this affects when ovulation occurs and therefore impacts your due date. For cycles longer than 28 days, your due date would be later; for shorter cycles, it would be earlier. Most calculators can adjust for different cycle lengths.

Resources & References

Encyclopedia Resources
  • Pregnancy - Wikipedia - Comprehensive overview of pregnancy, gestational development, and prenatal care from conception through childbirth.
  • Prenatal Development - Wikipedia - Detailed information about fetal development stages, from fertilization through the embryonic and fetal periods.
Educational Resources
  • Pregnancy - Wikipedia - Comprehensive overview of pregnancy, gestational development, and prenatal care from conception through childbirth.
  • Prenatal Development - Wikipedia - Detailed information about fetal development stages, from fertilization through the embryonic and fetal periods.