During pregnancy, certain lab tests are routinely performed on all women. They are done at specific times during the pregnancy to help your doctor identify possible problems with your pregnancy. They will also give clues to how your baby is doing. Other tests that may be done will depend on your medical history, age, family background, ethnic background, or exam results.
Initial Lab Tests – Done in 1st Trimester or at New OB Visit
- Pap Smear: Done to check for changes in the cervical cells that could lead to cancer.
- Cultures: A swab from your cervix will be done to check for STD’s (sexually transmitted disease) such as Gonorrhea and Chlamydia.
- Ultrasound: Used to determine Due Date
- Blood Work: You will be given an order to go to the lab to have the following blood tests drawn:
- CBC (complete blood count): This is used to detect anemia as well as any possible infection or clotting problems.
- Blood Type and Antibody Screen: Your blood type could be A, B, AB, or O. It can be Rh positive or Rh negative. Problems can arise when the mother’s Rh factor is negative and the baby’s is positive. To prevent these problems, the Rh negative mother will be given a Rhogam injection at 28 weeks.
- Syphilis: Syphilis is an STD. Syphilis can be treated. If you have syphilis and are not treated, you can pass it to your baby.
- Rubella: Your blood will be checked for antibodies against German measles (either from past infection or prior vaccination). If you are non-immune, while you are pregnant you should avoid anyone who has the disease. Vaccines for this disease are available, but you should not get them during pregnancy. If you are not immune to rubella, you will be given the vaccine after delivery.
- Hepatitis B: Hepatitis B is a virus that infects the liver. If you have this infection, you can pass it to your baby. A drug called Hepatitis B Immuno-Globulin may be given to help treat the illness. Your baby will be given the same medication and the vaccine after birth.
- HIV: HIV is the virus that causes AIDS. Pregnant women are tested even if they don’t have special risk factors. Your doctor will tell you that you are being tested for HIV. If you have HIV, there is a chance that you can pass it to your baby. You can be given medication during pregnancy to reduce this risk.
- Urinalysis: A urine sample will be collected to test for a urinary tract infection. If you have a UTI, you will be treated with antibiotics.
At Every Visit:
- Blood Pressure
- Urine Dip: checks for protein and glucose
- Measurement of uterine fundus
- Fetal Heart Rate
At 15-20 Weeks
Multiple Marker Screening and AFP: This is a screening test to determine if you have a higher than average risk of having a baby with certain birth defects. This is a blood test and does not pose a risk to the mother or the fetus. Positive results may indicate the baby may have:
- Neural tube defects: problems with the brain or spine such as spina bifida or anencephaly.
- Abdominal wall defects: problems with the body of the fetus.
- Genetic defects: physical or mental defects such as Down’s Syndrome.
Please remember that this is a screening test and is not used to diagnose these conditions. If your test is positive, additional testing will be ordered to diagnose any abnormalities. These include ultrasound and amniocentesis.
Ultrasound: Used to screen for malformations and appropriate fetal growth.
At 24-28 Weeks
Glucola or 1 hour GTT: This is a blood test to screen you for gestational diabetes.
Preparing for the 2 hour glucola:
- You should make your appointment for the first available time ( 8 AM ) , do not eat after midnight .
- Plan to be at the lab for at least 2 hours. You will also be seen for your scheduled prenatal visit
- The lab tech will give you a sweet drink called glucola. Do not eat or drink anything during this time.
- Bring a light snack to eat after the test. This helps to relieve nausea and shakiness that some people feel during the test. Do not eat this snack until the test is completed or it will have to be redone.
At 28 Weeks ( if Rh negative)
Antibody screen and Rhogam injection
At 35 Weeks
Group B Strep Culture: A swab is taken from the vagina and rectum to determine if the mother is a carrier of the bacteria. This is a type of bacteria that is normally found in the vagina and/or rectum of some women. It is not a sexually transmitted disease. It usually causes no symptoms or problems in adults. However, sometimes it can cause a serious infection in the newborn as it passes through the birth canal. If your test is positive, IV antibiotics will be given to you while in labor to prevent this infection in the newborn.
If any problems or complications arise in your pregnancy, additional testing may be ordered, such as:
- Ultrasound and/or Biophysical Profile
- Non-Stress Test
- Blood tests