The first trimester is full of important tests and scans to ensure a healthy start to your pregnancy.
Booking Visit: Your First Appointment
Usually scheduled at 8-10 weeks
This comprehensive visit establishes your baseline health and screens for potential issues.
Blood Tests at Booking Visit
Complete Blood Count (CBC):
- Checks hemoglobin (anemia screening)
- White blood cells (infection)
- Platelets (clotting ability)
Why it matters: Anemia in early pregnancy doubles preterm birth risk. Treatment starts immediately if detected.
Random Blood Sugar (RBS):
- Initial diabetes screening
- High levels warrant further testing
Infectious Disease Screening:
VDRL (Syphilis):
- Treatable infection
- Can harm baby if untreated
- Early treatment prevents complications
HIV:
- Important for your health
- Prevents mother-to-baby transmission
- Treatment during pregnancy highly effective
HBsAg (Hepatitis B):
- Checks for Hepatitis B infection
- Baby receives vaccine at birth if mother positive
- Prevents transmission
Blood Group and Rh Factor:
- Determines your blood type
- Critical for Rh incompatibility management
- If Rh-negative, you’ll need RhoGAM injections
Other Tests:
- Rubella immunity
- Thyroid function (if indicated)
- Hemoglobin electrophoresis (for thalassemia)
Booking Ultrasound Scan
Performed around 6-10 weeks
Purpose
Confirms:
- Pregnancy location (rules out ectopic)
- Viable pregnancy (heartbeat visible)
- Number of babies (twins, triplets?)
- Gestational sac and yolk sac
Due Date Calculation
Most accurate in first trimester:
- Measures crown-rump length (CRL)
- Baby’s size determines due date
- More accurate than date of last period
- Later scans less accurate for dating
Your due date may change based on this scan – trust the ultrasound measurement.
NT Scan (Nuchal Translucency)
Timing: 11-13 weeks (ideally 12 weeks)
This specialized ultrasound screens for chromosomal abnormalities, particularly Down syndrome.
What Is NT Scan?
Measures:
- Fluid at back of baby’s neck (nuchal translucency)
- Thicker measurement = higher risk for chromosomal issues
- Also checks nasal bone (absence increases risk)
Measures baby’s:
- Growth and development
- Major organ formation
- Anatomical structures
Understanding Risk Assessment
The scan provides a risk factor, not a diagnosis:
- Low risk: Under 1 in 1000
- Intermediate risk: 1 in 150 to 1 in 1000
- High risk: Greater than 1 in 150
Risk increases with maternal age:
- Age 20: 1 in 1500 risk
- Age 35: 1 in 350 risk
- Age 40: 1 in 100 risk
- Age 45: 1 in 30 risk
What Results Mean
Low risk:
- Reassuring, but not 100% guarantee
- No further testing needed (usually)
- Continue normal antenatal care
High risk:
- Doesn’t mean baby definitely has abnormality
- Further diagnostic testing offered
- Amniocentesis or CVS for definitive diagnosis
- Genetic counseling recommended
Remember: This is a screening test, not diagnostic. Many babies with high-risk results are perfectly healthy.
Follow-Up Tests if NT Is Abnormal
Amniocentesis
Performed: After 15 weeks
Procedure:
- Needle inserted through abdomen into amniotic sac
- Small amount of amniotic fluid withdrawn
- Tests fetal cells for chromosomal abnormalities
Accuracy: Over 99%
Risk: Small risk of miscarriage (about 1 in 200-400)
Chorionic Villus Sampling (CVS)
Performed: 11-14 weeks
Procedure:
- Sample of placenta tissue taken
- Through abdomen or cervix
- Tests for chromosomal abnormalities
Accuracy: Over 99%
Risk: Slightly higher miscarriage risk than amniocentesis
Non-Invasive Prenatal Testing (NIPT)
New option: Blood test
How it works:
- Analyzes fetal DNA in mother’s blood
- Screens for Down syndrome and other conditions
- No miscarriage risk
Accuracy: Very high (over 99% for Down syndrome)
Limitations:
- Not diagnostic (screening only)
- Not available everywhere
- Usually private/paid
First Trimester Symptoms
Common and Normal
Nausea and Vomiting:
- Affects 70-80% of women
- Usually improves after 12-14 weeks
- Morning sickness (but can be anytime)
Fatigue:
- Extreme tiredness
- Your body is working hard!
- Usually improves second trimester
Breast Tenderness:
- Hormones preparing for breastfeeding
- May need larger bra
Frequent Urination:
- Growing uterus presses on bladder
- Completely normal
Mood Swings:
- Hormones cause emotional ups and downs
- Normal but can be intense
When to Call Doctor
Warning signs:
- Severe vomiting (can’t keep anything down)
- Vaginal bleeding
- Severe abdominal pain
- No symptoms at all (suddenly)
- Fever over 100.4°F (38°C)
- Painful urination
First Trimester Do’s and Don’ts
Do:
✓ Take prenatal vitamins daily (especially folic acid)
✓ Eat small, frequent meals
✓ Stay hydrated (8-10 glasses water)
✓ Get plenty of rest
✓ Continue gentle exercise (if you feel up to it)
✓ Attend all appointments
Don’t:
✗ Take any medications without checking with doctor
✗ Drink alcohol
✗ Smoke
✗ Eat raw or undercooked meat, fish, eggs
✗ Eat unpasteurized dairy
✗ Clean cat litter (toxoplasmosis risk)
✗ Use hot tubs or saunas
✗ Engage in high-risk activities
Miscarriage: Understanding the Risk
Reality:
- 10-20% of known pregnancies end in miscarriage
- Most occur in first trimester
- Usually due to chromosomal abnormalities
- Not caused by normal activities
Warning signs:
- Bleeding with cramping
- Severe abdominal pain
- Tissue passing
If you experience these, call your doctor immediately.
Important: Most women who have one miscarriage go on to have healthy pregnancies.
Your First Trimester Checklist
✓ Schedule booking appointment (8-10 weeks)
✓ Complete all blood tests
✓ Have booking ultrasound
✓ Schedule NT scan (11-13 weeks)
✓ Take prenatal vitamins daily
✓ Avoid harmful substances
✓ Eat balanced diet (when you can!)
✓ Stay hydrated
✓ Rest when tired
✓ Report any warning signs immediately
Remember
The first trimester can be challenging with symptoms and anxiety, but these early tests ensure you and baby are healthy.
Every test is designed to give you and your healthcare team the information needed for the healthiest pregnancy possible.
You’re doing great. One week at a time.