Pregnancy Testing Timeline


Congratulations! Your pregnancy test has come back positive, and it’s time to go ahead and break out your calendar to schedule routine OB/GYN check-ups and diagnostic tests to make sure your baby’s growth and development stays on track throughout the next nine months. Here’s a timeline of what to expect during your prenatal care:

First Trimester – 0-12 Weeks
Prenatal visits every four weeks

6-12 Weeks
Your provider will check your uterus for size and growth and your baby’s heart tones. To detect abnormalities and genetic disorders, like Down syndrome or cystic fibrosis, a transvaginal chorionic villus sampling (CVS) is available at this time if you so choose. Also, depending on family history, your baby may be screened for cardiac defects with other test methods.

Second Trimester – 13-27 Weeks
Prenatal visits every two weeks

13-24 Weeks
An ultrasound is performed to determine the date of your pregnancy and to evaluate your baby’s anatomy. An earlier examination gives the most accurate dating, and a later examination shows your baby’s anatomy in greater detail.

15-20 Weeks
You may be advised to have an amniocentesis, an amniotic-fluid test to check if your baby has any type of infection or chromosome abnormalities. Maternal serum alphafetoprotein (AFP) testing also is offered to all women to screen for neural tube defects.

20-24 Weeks
Your doctor will talk to you about the symptoms and signs of preterm labor and the rupture of membranes.

24 Weeks-Delivery
Your doctor will perform an ultrasound examination when needed. Typically, your baby’s size and growth are checked when your baby’s height is 3 centimeters less than or more than expected for gestational ages. In multiple pregnancies, an ultrasound should be performed every four weeks to check for any unusual growth.

26-28 Weeks
You will be tested for gestational diabetes by drinking a sugar-enhanced drink, followed by a blood test to test blood glucose. Any abnormal results should be followed up with a three-hour glucose tolerance test.

28 Weeks-Delivery
Your doctor will determine your baby’s position and presentation, and will ask you questions at each visit for symptoms or signs of preterm labor or rupture of membranes. Your doctor also will assess your perception of your baby’s movement.

Third Trimester
36 Weeks-Delivery
Prenatal visits every week

35-37 Weeks
Your doctor will screen for Group B Strep, an infection that can cause inflammation of your baby’s lungs, spinal cord or brain, during your last trimester by taking a vaginal and rectal swab. If your results are positive, you will receive preventative penicillin during labor for a vaginal delivery. If you plan to have a Cesarean section, your baby will not be affected.

36 Weeks-Delivery
Weekly cervical examinations are not necessary unless there are specific clinical situations. Your doctor must confirm your baby’s lung maturity before any elective delivery is performed (whether by induction or C-section) prior to 39 weeks of gestation.

41 Weeks and Beyond
Your doctor will examine your cervix to determine whether or not you will have a successful induction of labor.

Source: Pregnancy & Parenting Center at