young woman having a consultation with her doctor

Types


What Types of Pregnancy Screening Tests Should I Have?

Pregnancy screening tests are typically performed during the first and second trimesters to determine if the baby is developing normally or is likely to have certain birth defects and to screen for health conditions that could be dangerous to the mother or the baby. Examples of some common pregnancy screening tests include:

  • Ultrasounds to check the size, position, and general development of the baby
  • Blood tests for Rh compatibility
  • Blood tests for syphilis, hepatitis B, and HIV
  • Blood tests for gestational diabetes
  • Blood tests for group B streptococcus

 

Many of the tests are available at your local MD Now Clinic. Depending upon your age and other risk factors, your provider may recommend more advanced tests to check for Down syndrome and other genetic abnormalities.

Should I Have a Gestational Diabetes Test?

Even non-diabetic women can develop high blood sugar during pregnancy, which is known as gestational diabetes. The condition is primarily caused by the hormonal changes that occur during pregnancy that affect the way the body responds to insulin; however, weight gain, an increase in fat deposits, and a decrease in physical activity may also play a role. Gestational diabetes normally resolves on its own following birth, but it can cause a number of complications, including high birth weight, premature birth, and an increased risk of preeclampsia. Although a gestational diabetes test is recommended for all pregnant women, it is especially important for women with the following risk factors:

  • A history of prediabetes or gestational diabetes
  • A family history of type 2 diabetes
  • A history of polycystic ovary syndrome or other hormone disorders
  • Being over the age of 25
  • Excessive weight gain during pregnancy
  • Previously giving birth to a baby weighing over 9 pounds or that had a birth defect
  • Previously having an unexplained miscarriage or stillbirth
  • Being of Asian, African, American Indian, Pacific Islander, or Hispanic descent

How Early Can I Take a Pregnancy Test?

Most pregnancy tests can detect a pregnancy 10 to 14 days following conception; however, it is best to wait until the week after your missed period for the most accurate result. If you don’t want to wait until you have missed a period, it is a good idea to at least wait until one to two weeks after you have had sex to give time for the egg to implant and your body to develop detectable levels of the pregnancy hormone known as hCG or human chorionic gonadotropin.


Reliability


Are Digital Pregnancy Tests Reliable?

At-home pregnancy tests, including an early result first-response test, can be up to 99% accurate when used according to directions. Several factors may cause you to have a positive pregnancy test even when you are not pregnant:

  • If you wait too long to read the test, the urine can start to evaporate, which can create faint lines resembling a positive result. It is important to follow the manufacturer’s instructions to reduce the likelihood of getting a false positive.
  • If the test is expired, the chemical on the test strip that detects the hCG may not work properly and give you a false positive.
  • You may get a false positive if you take a pregnancy test shortly after taking a fertility drug containing hCG.
  • You may have conceived but miscarried shortly after implantation. This is known as a chemical pregnancy.
  • It can take up to six weeks for hCG levels to return to normal following a birth or miscarriage, and it is possible for the residual hormone to result in a positive pregnancy test even though you are no longer pregnant.
  • It is possible to have a positive pregnancy test with an ectopic pregnancy where the fertilized egg grows outside of the uterus.

How Does an Early Result Pregnancy Test Work?

Pregnancy detector tests check the urine for the hormone hCG. The placenta starts producing hCG almost immediately after the fertilized egg implants in the uterus and levels normally double every 72 hours through the eighth to 11th week of pregnancy. A first-response early result pregnancy test can be used at home to check for the presence of hCG in the urine. A positive pregnancy test means that the hormone is present. A positive pregnancy test is normally indicated by a change in color, a line, the word “pregnant,” or a plus symbol.

Is It Possible to Have a False Negative Blood Pregnancy Test?

Blood pregnancy tests are up to 99% accurate. Similar to the at-home urine tests, a blood pregnancy screening checks for the presence of hCG in the blood. Although rare, it is possible to get a false negative result if you test too early since there may not be enough hCG in the blood to be detected. This is why most providers suggest waiting until you have a missed period. Certain medications, such as promethazine and certain diuretics, may also lower the amount of hCG in the blood and affect the accuracy of test results.


Paternity Testing


When Can Prenatal Paternity Testing Be Done?

Depending on the type of test, it is possible to perform a prenatal paternity test as early as the eighth week of pregnancy.


The content provided on the MD Now website is for informational purposes only and is not intended to be a substitute for receiving medical care and treatment from a qualified healthcare provider. Never delay seeking advice, evaluation, and treatment from a medical professional because of what you’ve read on this site, since the information provided may not apply to you or your symptoms.