Labs During First Prenatal Visit

There are many tests that will be done with the first prenatal visit. These include urine tests, a pap smear, cervical cultures, and several blood tests. Some things present in the woman’s body will cause no problems for her, however, they may cause problems for the baby. The tests that are performed in pregnancy look for issues that can be treated so as to decrease the risks for the baby.

The urine will be screened for several things. A pregnancy test will be done to make sure that there really is a pregnancy. The urine will be tested for glucose as this can be a sign of diabetes. The urine is also screened for protein looking for preeclampsia. It would be very unusual for preeclampsia to be present in the first prenatal visit, although I have seen this. This mostly serves as a baseline, in case preeclampsia develops later in pregnancy. The urine will be collected at each follow up visit to check for glucose and protein. At the first prenatal visit the urine will also be sent for a culture to see if there is bacteria in the urine. In the non-pregnant state, bacteria in the urine that does not cause symptoms is generally not treated. In pregnancy it is. This is because women that have bacteria in their urine during pregnancy have a 25% chance of developing a kidney infection if not treated. Kidney infections can become very serious.

A pap smear will typically be done at the first visit, as well as cervical cultures for gonorrhea and chlamydia.  Don’t be insulted by these cultures, they are done on every patient. If you have an infection of the cervix it is important that it is treated and cleared prior to delivery so that the baby does not get the infection during birth

A number of blood tests will also be done. A blood count looking for anemia will be done. If anemia is present, iron will likely be prescribed. Your blood type and Rh factor will be checked. If you are Rh negative, you will need a medication called Rhogam at 28 weeks and after delivery. Blood tests will also look for certain infections; hepatitis, syphilis, and HIV will all be checked for. It is very important to know if you are HIV positive during pregnancy. HIV positive women who are not treated have a 30% of passing the infection to the baby. HIV positive women who are adequately treated have less than a 5% chance of transmitting the infection to the baby. So treatment is extremely important for the baby’s health. If you are hepatitis positive there are interventions that can be done to protect the baby. Syphilis is also treatable and treatment can prevent birth defects. Pregnancy can occasionally cause a false positive syphilis screen. Fortunately thee is a follow up test that can be done to find out if it is a false positive or if syphilis is really present. So if the initial syphilis test is positive but the follow up is negative do not be alarmed.

There are other tests that can be done in some circumstances. A test to check for the cystic fibrosis gene can be done. Cystic fibrosis is a disease that requires a gene from both parents to be active. Some people carry just one gene for the disease. In this case they are considered a carrier because they do not have the disease but can pass the gene on. If your carrier status is unknown it may be worth checking. If you do not carry the gene, the baby will not have cystic fibrosis. If you are a carrier, your partner can be screened. If you both are carriers the baby will have a 25% chance of getting cystic fibrosis. Sickle cell anemia is another disease that requires genes from both parents. Similar to cystic fibrosis. There is a test for sickle cell that can be done to check for the carrier state. There are other blood tests that may be ordered as well depending on your unique circumstance and risk factors.