Pregnancy Week by Week
(First, Second, and Third Trimester)

Pregnancy facts*

*Pregnancy facts medical author:

  • A normal pregnancy lasts about 40 weeks and is grouped into three trimesters .
  • Symptoms of early pregnancy include the absence of menstrual periods, breast changes, tiredness, nausea, mood swings, or other symptoms.
  • A pregnancy test measures the hormone human chorionic gonadotropin in the urine or blood.
  • Symptoms of late pregnancy can include heartburn, difficulty sleeping, swelling of the ankles or fingers, hemorrhoids, and mild contractions.
  • By the end of 37 weeks, a baby is considered full term and its organs are ready to function on their own.
  • As you near your due date, your baby may turn into a head-down position for birth. Most babies "present" head down.
  • Babies at birth typically weigh between 6 pounds 2 ounces and 9 pounds 2 ounces and are 19 to 21 inches long. Most full-term babies fall within these ranges.

Introduction

Pregnancy lasts about 40 weeks, counting from the first day of your last normal period. The weeks are grouped into three trimesters (TREYE-mess-turs). Find out what's happening with you and your baby in these three stages.

Medically Reviewed by a Doctor on 3/14/2014

Patient Comments

Viewers share their comments

Pregnancy - Describe Your Experience Question: Please describe usual or unusual experiences had with your pregnancy, food cravings, morning sickness, edema (etc.)
Pregnancy - Signs Question: How did you find out you were pregnant?
Pregnancy - Morning Sickness Question: Did you suffer from morning sickness during your pregnancy? What helped relieve your symptoms?
Pregnancy - Heartburn and Indigestion Question: Did you have heartburn or indigestion during your pregnancy? What helped to relieve symptoms?
Pregnancy - Stretch Marks and Skin Changes Question: What skin changes did you notice during your pregnancy? How did you treat them?
Pregnant or Not?

Pregnant or Not? How To Know

To learn whether you are pregnant or not, a pregnancy test may provide you with the answer. This test can be done in the privacy of your home using one of several available test kits. Or the test can be performed in your doctor?s office or clinic. Home pregnancy tests are always done on urine while those in a doctor?s office or clinic may be done on urine or blood.