First Trimester Pregnancy Tests

Medically Reviewed by Dr. K on 21 April 2021

Table of Contents :

  1. First Trimester of Pregnancy
  2. Blood Test
  3. Urine Test
  4. Genetic Test
  5. Ultrasound Scans
  6. Non-Invasive Prenatal Testing Screening (NIPT)
  7. Chorionic villus sampling (CVS)

First Trimester of Pregnancy


During the first trimester of your pregnancy, you will be subjected to a wide array of tests.


Blood Test


The doctor or midwife can determine your blood type and Rh (rhesus) factor, scan for anaemia, check for rubella (German measles) protection, and monitor for hepatitis B, syphilis, HIV, and other sexually transmitted diseases at one of the initial exams. 

You might be given scans and genetic testing to determine your likelihood for diseases like Tay-Sachs, cystic fibrosis, and sickle cell anaemia (if this weren’t performed during a preconception visit) based on your racial, ethnic, or family history. If necessary, tests for diseases including toxoplasmosis and varicella (the virus that induces chickenpox) can be performed. Your doctor will also want to monitor the levels of hCG, a hormone produced by the placenta, and/or progesterone, a hormone that aids in pregnancy maintenance.

Urine Tests


The doctor or midwife can ask for a urine sample early on to check for symptoms of kidney infection and, if possible, to confirm the pregnancy by checking the hCG amount. (A blood hCG examination could be used to confirm pregnancy instead.) After that, urine tests would be taken on a routine basis to check for glucose (a symptom of diabetes) and protein, which may signify the possibility of preeclampsia, a pregnancy-related condition marked by elevated blood pressure. 


Genetic Tests


You will be given genetic tests in the latter stages of the first trimester. You must first determine whether or not you want some genetic tests at all. Some people believe that these studies can give them unnecessary discomfort, and they will rather wait before the baby is born to ensure that the baby is genetically normal. Some people tend to perform more of the research they can, despite the fact that these tests occasionally are not 100% accurate. Before continuing, discuss the benefits and drawbacks with your doctor to determine if genetic testing is appropriate for you and your pregnancy. There are several genetic testing methods available, including blood tests alone or ultrasounds with little harm to the child. If the results of these noninvasive procedures appear irregular, you will be given further monitoring. You will then determine whether or not you want to take the exams.


Ultrasound Scans


Between 11 and 14 weeks of pregnancy, one first semester genetic examination that incorporates a blood test with an ultrasound to check for Down syndrome could be eligible. An ultrasound measurement of the skin at the back of the foetus’ neck is combined with the findings of a blood test that tests hCG and/or PAPP-A (pregnancy-associated plasma protein A) in maternal blood (called nuchal translucency). The technique could be able to detect a significant number of instances of Down syndrome and other hereditary disorders. If the findings are conclusive, a more invasive diagnostic procedure such as CVS is used, as in other screening procedures.


Non-Invasive Prenatal Testing Screening (NIPT)


This cell-free foetal DNA examination may be performed as early as 10 weeks after conception. A blood examination is used to determine the volume of free foetal DNA in a mother’s blood. The exam is believed to be capable of detecting 99% of all Down syndrome births. It even looks for chromosomal defects in some people.


Chorionic villus sampling (CVS)


This optional, invasive test would be given to you between 10 and 12 weeks of pregnancy whether you’re 35 or older, have a family history of such illnesses, or have had a favourable outcome on non-invasive genetic testing. Down syndrome, sickle cell anaemia, cystic fibrosis, haemophilia, and muscular dystrophy are among the hereditary abnormalities that CVS can detect. To extract a tissue sample from the placenta, either a small catheter is inserted through the cervix or a needle is inserted through your abdomen. The treatment has a 1% chance of causing a miscarriage but is 98% successful in detecting such chromosomal birth defects. However, unlike amniocentesis, it is ineffective in identifying neural tube abnormalities such as spina bifida and anencephaly, as well as abdominal wall defects. 

And sure to talk to the doctor about all of your testing options so that you can choose the ones that are right for you.


Referenced on  10.4.2021

  1. Danforth’s Obstetrics and Gynecology, 9th edition, 2003.
  2. Gabbe: Obstetrics-Normal and Problem Pregnancies, 4th edition, 2002.
  3. March of Dimes.
  4. WebMD Medical Reference provided in collaboration with The Cleveland Clinic: “Pregnancy: Chorionic Villus Sampling."
  5. Ob/Gyn Ultrasound at the Fairbanks Clinic, Fairbanks, Alaska.
  6. UCSF Nedical Center: “FAQ: Cell-Free Fetal DNA Testing."

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