Pregnancy typically lasts just over nine months or about 38 weeks from the time of conception to childbirth.

Overview and Symptoms

It’s divided into three trimesters:

  • First trimester is from week one through 12. This is when the amniotic sac forms around the fertilized egg and the placenta develops.
  • Second trimester, week 13 to 28, is when movement of the fetus may be felt. At 28 weeks, 90% of babies can survive outside the uterus if provided high-quality medical care.
  • Third trimester is from week 29 through 40 weeks. Fetal development continues as the baby opens his or her eyes, gains weight and prepares for delivery.

Some of the symptoms of pregnancy include:

  • food aversions
  • mood swings
  • abdominal bloating
  • fatigue
  • increased urinary frequency
  • breast tenderness
  • nausea
  • constipation
  • pelvic girdle pain
  • back pain


There are a number of over-the-counter medications available to alleviate some of the symptoms of pregnancy.

Prenatal care is important to keep you and your baby healthy. Doctors can spot health problems early when they see mothers regularly; early treatment can cure many problems and prevent others.

Regular testing throughout your pregnancy will assure you and your baby are healthy.

Learn More

The Department of Obstetrics and Gynecology at BIDMC provides outstanding care for all women throughout their lives, in a friendly, comfortable and safe environment.

Your Pregnancy