What scans are necessary during the first trimester?

One way to ensure your little one is growing just fine is via ultrasound scans. These scans are more than just beautiful moments where you get your first glimpse of your baby; they are important in ensuring everything is going well. Understanding which scans are required, what they look for, when they should be performed, and why they are important will make you feel more prepared and confident. 

Early pregnancy scan

The early pregnancy scan, also known as the dating scan, is typically the first ultrasound of the pregnancy. It confirms the pregnancy, determines how far along you are, and looks for any early warning signs. This scan is done between 6 and 9 weeks of pregnancy. If you are unsure of your last menstrual period (LMP), your healthcare provider may recommend this scan to find out how far along you are.

• What does this scan look for?

  • Confirmation of pregnancy: Ensures that the pregnancy is developing within the uterus (excludes ectopic pregnancy).
  • Gestational age: Calculated by measuring the baby's crown-rump length (CRL) and estimating your due date.
  • Heartbeat detection: The baby's heartbeat should be visible at 6-7 weeks.
  • Number of babies: The number of babies determines whether you are expecting one or more.
  • Check for early pregnancy complications: Helps to detect conditions such as blighted ovum (when the pregnancy sac develops but not the embryo) and molar pregnancy.

 

• Why is this scan important?
  • It provides early reassurance that your baby is developing normally.
  • It helps in accurately dating the pregnancy, ensuring that all subsequent scans and tests are timed properly.
  • If you have a history of miscarriage or ectopic pregnancy, this scan can help detect problems early.

 

• How is it done?

  • Before 8 weeks, this scan is usually done transvaginally for better clarity.  From 8 weeks on, an abdominal ultrasound may be sufficient.

Nuchal Translucency (NT) Scan (required)

• What is the NT Scan?
  • The Nuchal Translucency (NT) scan is an important screening test that assesses the risk of chromosomal abnormalities in the baby, including Down syndrome (Trisomy 21), Edwards syndrome (Trisomy 18), and Patau syndrome (Trisomy 13). This scan is performed between 11 and 14 weeks of pregnancy.

 

• What does this scan look for?
  • Nuchal translucency measurement: This is a measurement of the fluid collection in the back of the baby's neck. Excess fluid may indicate an increased risk of chromosomal abnormalities.
  • Nasal bone presence: The absence of a nasal bone can indicate Down Syndrome.
  • Baby's overall development: Ensure that the baby is growing normally at this stage.
  • Confirm pregnancy viability: By 11-14 weeks, the baby's heartbeat and movements should be visible.

 

• When is it required?
  • It is especially recommended for women over 35 and those with a family history of genetic conditions.
  • It is frequently combined with a blood test (first-trimester screening) to provide a more precise risk assessment.

 

• Why is this scan important?
  • It helps in the early detection of potential chromosomal issues, allowing parents to make more informed decisions.
  • Additional tests such as Non-Invasive Prenatal Testing (NIPT) or Chorionic Villus Sampling (CVS) may be advised if the scan and blood tests show a high risk.

 

• How is it done?
  • An abdominal ultrasound is performed by placing a probe on your belly and displaying the baby's image on the screen.

Viability scan (optional)

• What is a viability scan?
  • A viability scan is an ultrasound performed to confirm the pregnancy's progress in cases where early pregnancy loss is a concern. It is done between 6 and 10 weeks of pregnancy, particularly for women who have previously miscarried or undergone fertility treatments.

 

• What does this scan look for?
  • Confirms the baby's heartbeat and promotes healthy development.
  • If you've had spotting or cramping, this test will detect the cause of the bleeding.
  • If any risk factors exist, ectopic pregnancy is ruled out.
  • Check for multiple pregnancies if you've had fertility treatments.

 

• Why is this scan important?
  • It provides early reassurance to women who are at higher risk of pregnancy loss.
  • If a miscarriage is suspected, it can help determine whether medical treatment is required.
  • It ensures that everything is going as it should.

 

• How is it done?
  • To improve accuracy, the procedure is usually performed transvaginally.

Chorionic Villus Sampling (CVS)(optional)

• What is CVS?
  • Chorionic Villus Sampling (CVS) is an optional diagnostic test that examines a small sample of placental tissue to detect genetic conditions. It is usually done between 10 and 13 weeks.

 

• What does this scan look for?
  • Chromosomal abnormalities like: 
    • Down syndrome
    • Edwards syndrome
    • And Patau syndrome
  • Cystic fibrosis
  • Sickle cell disease
  • And thalassemia

 

• When is it required?
  • If the NT scan or first-trimester screening results show a high risk.
  • If the mother's family history includes genetic conditions.

 

• Why is this scan important?
  • It provides a definitive diagnosis rather than simply a risk factor.
  • Allows parents to make informed decisions about their pregnancy.

 

• How is it done?
  • A thin needle is inserted into the abdomen (or cervix) to collect placental tissue.

Noninvasive Prenatal Testing (NIPT) (optional)

• What is NIPT?
  • NIPT is a blood test that detects chromosomal abnormalities by analyzing fetal DNA in the mother's bloodstream.

 

• What does this scan look for?
  • Down's syndrome, Edwards syndrome, and Patau syndrome.

 

• When is this scan required?
  • This can be completed as early as 10 weeks.
  • Recommended for women over the age of 35 and those with abnormal NT scan results.

 

• Why is this scan important?
  • It is 99 percent accurate and non-invasive.
  • If the results indicate a high risk, additional testing such as CVS may be required.

Each scan in the first trimester serves a specific purpose; to ensure that your pregnancy is progressing normally and that your baby is healthy. Whether it's confirming your due date, checking for potential issues, or simply giving you peace of mind, these scans provide reassurance during this exciting time. Trust your instincts, ask questions, and take comfort in knowing that these scans are here to help you and your baby on your journey.