Pregnancy Calendar — Week-by-Week Timeline & What to Expect

Your complete guide to pregnancy week by week with fetal development, symptoms, and checklists.

Your Pregnancy Journey

Pregnancy is an incredible journey that lasts approximately 40 weeks (or 9 months) and is divided into three trimesters. Each month brings new developments for both you and your baby. Use this calendar to understand what to expect during each stage of your pregnancy.

Share This Pregnancy Calendar:

Facebook Twitter WhatsApp Copy Link

First Trimester (Months 1-3)

First Trimester

Month 1: Weeks 1-4

Baby's Development

  • Conception occurs
  • Fertilized egg implants in the uterine wall
  • Neural tube begins to form
  • Heart begins to develop

Your Body

  • Missed period (if tracking)
  • Breast tenderness
  • Fatigue
  • Nausea (morning sickness may begin)

Important Notes

  • Take prenatal vitamins with folic acid
  • Avoid alcohol, tobacco, and certain medications
  • Schedule your first prenatal appointment
First Trimester

Month 2: Weeks 5-8

Baby's Development

  • Heartbeat detectable
  • Brain and spinal cord develop
  • Limbs begin to form
  • Facial features start to appear
  • Size: About 1 inch long

Your Body

  • Morning sickness may peak
  • Frequent urination
  • Food aversions or cravings
  • Breast changes continue

Important Notes

  • First prenatal visit typically scheduled
  • Blood tests and screenings may be done
  • Continue healthy habits
First Trimester

Month 3: Weeks 9-12

Baby's Development

  • All major organs formed
  • Fingers and toes distinct
  • External genitalia developed
  • Size: About 3 inches long, 1 ounce

Your Body

  • Morning sickness may subside
  • Energy levels may increase
  • Belly begins to show
  • Increased blood volume

Important Notes

  • End of first trimester
  • Nuchal translucency screening (weeks 11-14)
  • Gender may be visible on ultrasound

Second Trimester (Months 4-6)

Second Trimester

Month 4: Weeks 13-16

Baby's Development

  • Skeleton begins to harden
  • Sex organs developed enough to determine gender
  • Meconium (first stool) forms in intestines
  • Size: About 4-5 inches long, 4-5 ounces

Your Body

  • "Golden period" - energy returns
  • Weight gain becomes more noticeable
  • Skin changes (linea nigra, darkened areolas)
  • Blood volume continues to increase

Important Notes

  • Anatomy scan ultrasound (18-22 weeks)
  • Maternity clothes shopping
  • Continue regular prenatal visits
Second Trimester

Month 5: Weeks 17-20

Baby's Development

  • Hearing develops
  • Fine hair (lanugo) covers body
  • Permanent tooth buds form
  • Size: About 6-7 inches long, 10-12 ounces

Your Body

  • Feel baby move (quickening) - first time mothers
  • Belly grows more prominent
  • Stretch marks may appear
  • Breasts may leak colostrum

Important Notes

  • Baby's heartbeat may be heard with Doppler
  • Glucose screening (24-28 weeks)
  • Start birth plan considerations
Second Trimester

Month 6: Weeks 21-24

Baby's Development

  • Lungs begin to make surfactant
  • Brain development accelerates
  • Eyelids open
  • Size: About 12 inches long, 1.5 pounds

Your Body

  • Weight gain continues
  • Back pain may begin
  • Braxton Hicks contractions
  • Sleep position becomes important

Important Notes

  • Baby may survive outside womb with medical help
  • Continue regular prenatal visits
  • Prepare for third trimester

Third Trimester (Months 7-9)

Third Trimester

Month 7: Weeks 25-28

Baby's Development

  • Brain development continues rapidly
  • Lungs mature
  • Eyes can open and close
  • Size: About 14 inches long, 2-3 pounds

Your Body

  • Increased fatigue
  • Shortness of breath
  • Swelling in hands and feet
  • Prepare nursery and baby items

Important Notes

  • Glucose tolerance test
  • Baby's movements should be monitored
  • Finalize birth plan
Third Trimester

Month 8: Weeks 29-32

Baby's Development

  • Bones harden
  • Still gaining weight rapidly
  • Eyes can focus
  • Size: About 16 inches long, 4-5 pounds

Your Body

  • Increased back pain
  • Difficulty sleeping
  • More frequent urination
  • Pelvic pressure increases

Important Notes

  • Prepare for labor and delivery
  • Attend childbirth classes
  • Pack hospital bag
Third Trimester

Month 9: Weeks 33-40

Baby's Development

  • Full-term at 37 weeks
  • Continued weight gain
  • Positioning for birth (head down)
  • Size: About 20 inches long, 7-8 pounds

Your Body

  • Nesting instinct may occur
  • Increased pelvic pressure
  • Braxton Hicks may become more frequent
  • Possible signs of labor

Important Notes

  • Final prenatal visits
  • Discuss labor signs with healthcare provider
  • Be ready for baby's arrival

Tips for a Healthy Pregnancy

Following these guidelines can help ensure a healthy pregnancy for both you and your baby:

Nutrition

Exercise

Healthcare

Frequently Asked Questions

What tests happen at 12, 20, 28 weeks?

At 12 weeks: Nuchal translucency screening and blood tests for Down syndrome. At 20 weeks: Anatomy scan ultrasound to check baby's development. At 28 weeks: Glucose tolerance test for gestational diabetes.

How to use this calendar with your provider appointments?

Bring this calendar to your prenatal appointments to discuss what to expect in upcoming weeks. Use it to prepare questions about tests, symptoms, and development. It can help you stay informed and engaged in your prenatal care.

Can symptoms vary week to week?

Yes, pregnancy symptoms can vary greatly between individuals and even from one pregnancy to another. Some weeks you may feel great, while others you may experience more discomfort. This is normal, but contact your healthcare provider with any concerning symptoms.

When should I start prenatal vitamins?

It's recommended to start prenatal vitamins with folic acid at least one month before trying to conceive, if possible. If you didn't start before conception, begin as soon as you find out you're pregnant. Folic acid is especially important in the early weeks for neural tube development.

How to track fetal movement?

Starting in the second trimester, you'll begin to feel your baby move. By the third trimester, healthcare providers often recommend tracking movements. If you notice a significant decrease in movement, contact your healthcare provider. Each baby has their own pattern, so get to know your baby's activity rhythm.

What are the different methods for predicting baby gender?

While ultrasound and NIPT are the most accurate medical methods for gender prediction, there are several traditional methods that many people enjoy for fun. These include the Nub Theory (75% accurate at 12-14 weeks), Chinese Gender Chart, and Shettles Method. For detailed information about these and other gender prediction methods, including accuracy rates and how they work:

Related Tools

Ovulation Calculator

Calculate your most fertile days to increase chances of conception.
Due Date Calculator

Calculate your estimated due date based on your last menstrual period.
Pregnancy Week Calculator

Track your pregnancy progress week by week with important milestones.