Pregnancy Week by Week
(First, Second, and Third Trimester)
*Pregnancy facts medical author: Melissa Conrad Stöppler, MD
- 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.