Pregnancy Calendar

About Pregnancy Calendar

Welcome to the Pregnancy Calendar, a comprehensive free online tool that helps you track your pregnancy journey week by week. Whether you know your due date, last menstrual period (LMP), or conception date, this calculator creates a personalized 40-week pregnancy calendar with development milestones, baby size comparisons, trimester progress tracking, and important appointment reminders.

How is a Pregnancy Due Date Calculated?

A pregnancy due date is typically calculated as 280 days (40 weeks) from the first day of your last menstrual period (LMP). This is based on the assumption of a 28-day menstrual cycle with ovulation occurring around day 14. If you know your conception date, the due date is 266 days (38 weeks) from conception. Your healthcare provider may adjust your due date based on ultrasound measurements, especially if your cycle length differs from 28 days.

Calculation Methods

• From Due Date: If your doctor has already provided your estimated due date, enter it directly to generate your complete pregnancy calendar.
• From LMP: Enter the first day of your last menstrual period. The calculator adds 280 days to determine your due date.
• From Conception Date: If you know when conception occurred (through IVF, ovulation tracking, etc.), enter that date. The calculator adds 266 days for your due date.

What are the Three Trimesters of Pregnancy?

Pregnancy is divided into three trimesters, each with distinct developmental stages and experiences:

First Trimester (Weeks 1-12)

The first trimester is a critical period when all major organs and systems begin forming. During this time, many women experience morning sickness, fatigue, and breast tenderness. Key developments include the formation of the neural tube, heart, and basic organ structures. By week 12, the baby has developed fingerprints and can move, though movements are not yet felt.

Second Trimester (Weeks 13-26)

Often called the "honeymoon phase," the second trimester typically brings increased energy and reduced nausea. You will start showing and may feel the first baby movements (quickening) around weeks 18-20. The anatomy scan at week 18-20 provides a detailed look at your baby's development. By the end of this trimester, your baby can hear sounds and respond to light.

Third Trimester (Weeks 27-40)

The final trimester is marked by rapid baby growth and final organ maturation. You may experience Braxton Hicks contractions, increased fatigue, and more frequent prenatal visits. The baby gains about half a pound per week and moves into position for birth. Full term begins at 37 weeks, when the baby is considered ready for birth.

What is the Viability Milestone in Pregnancy?

The viability milestone is reached around 24 weeks of pregnancy. This is when a baby may survive outside the womb with intensive medical care if born prematurely. However, babies born this early face significant health challenges including respiratory issues, developmental delays, and other complications. The chances of survival and healthy development improve substantially with each additional week in the womb, which is why reaching full term (37+ weeks) is the goal.

When is a Pregnancy Considered Full Term?

Pregnancy term classifications are important for understanding your baby's readiness for birth:

• Early Term: 37 weeks 0 days through 38 weeks 6 days
• Full Term: 39 weeks 0 days through 40 weeks 6 days
• Late Term: 41 weeks 0 days through 41 weeks 6 days
• Post-Term: 42 weeks 0 days and beyond

Babies born at full term (39-40 weeks) have the best health outcomes as their lungs, brain, liver, and other organs have had adequate time to fully mature.

What Prenatal Tests are Recommended During Pregnancy?

Various prenatal tests and appointments are scheduled throughout pregnancy to monitor both mother and baby health:

First Trimester Tests

• Week 6-8: First prenatal visit with blood work, urine tests, and pregnancy confirmation
• Week 8-10: First ultrasound to confirm due date and check heartbeat
• Week 10-13: NIPT (Non-Invasive Prenatal Testing) for chromosomal screening
• Week 11-13: NT scan (Nuchal Translucency) for chromosomal abnormalities

Second Trimester Tests

• Week 15-20: AFP (Alpha-fetoprotein) blood test
• Week 18-20: Anatomy scan (detailed ultrasound) to check all organ systems
• Week 24-28: Glucose screening test for gestational diabetes

Third Trimester Tests

• Week 28: Rhogam shot if Rh negative blood type
• Week 35-37: Group B Strep test
• Week 36+: Weekly visits to monitor position and check for labor signs

How Can I Track My Baby's Size During Pregnancy?

Baby size is commonly compared to fruits and vegetables to help visualize growth week by week:

• Week 4: Poppy seed (1 mm)
• Week 8: Kidney bean (1.6 cm)
• Week 12: Lime (5.4 cm)
• Week 16: Avocado (11.6 cm)
• Week 20: Banana (16.4 cm) - Halfway point!
• Week 24: Ear of corn (30 cm)
• Week 28: Eggplant (37.6 cm)
• Week 32: Jicama (42.4 cm)
• Week 36: Romaine lettuce (47.4 cm)
• Week 40: Small pumpkin (51.2 cm) - Due date!

How to Create Your Pregnancy Calendar

1. Choose your calculation method: Select how you want to calculate your pregnancy dates - by Due Date if you already know it from your doctor, by Last Menstrual Period (LMP) if you remember when your last period started, or by Conception Date if you know when you conceived.
2. Enter your date: Input the corresponding date using the date picker. The calculator will automatically compute all other important dates.
3. Generate your calendar: Click "Create Pregnancy Calendar" to generate your personalized 40-week pregnancy calendar.
4. Review your pregnancy timeline: View your current week status, progress percentage, days until due date, and important milestone dates.
5. Explore weekly details: Click on any week to see baby size comparisons, development milestones, and recommended appointments.

Understanding Your Results

Your personalized pregnancy calendar includes:

• Current Week Display: Shows which week you are currently in with days remaining in the week
• Progress Tracker: Visual progress bar showing percentage of pregnancy completed with trimester indicators
• Days Until Due: Countdown to your estimated due date
• Baby Size: Current size comparison to a fruit or vegetable
• Development Milestone: What is happening with your baby this week
• Key Dates Timeline: Important dates including conception, trimester endings, viability, full term, and due date
• 40-Week Calendar: Complete week-by-week breakdown with dates and development information

Related MiniWebtools:

Pregnancy Calculators:

• Due Date Calculator
• How Many Weeks Pregnant Am I?
• Pregnancy Calendar