Obstetrics and pregnancy care
First-trimester screening
Risk estimation for selected chromosomal conditions using maternal information, ultrasound and, depending on the programme, blood tests.
Explained in clear language
What it is
It is a screening test, not a diagnostic test. It combines factors such as gestational age, nuchal translucency and biochemical markers to calculate a probability.
How it is performed
- 1
Individual assessment and indication
- 2
Explanation, alternatives and consent
- 3
Procedure with appropriate safeguards
- 4
Results, aftercare and follow-up
Askabide visual archive
The procedure, also explained through images
The photographs come from Askabide’s clinical and “more information” sections. They have been selected by clinical area to support the explanation; not every image is a literal representation of each manoeuvre and none replaces an individual medical explanation.
Assessment and indication
The indication is decided after listening to the reason for attending, reviewing history and explaining the clinical question that needs to be answered.
How it is carried out
The technique, sample collection, device or intervention is adapted to the individual situation and explained before it starts.
Results and follow-up
The result is not interpreted in isolation: symptoms, examination, age, history and complementary tests are considered together.
Clinical interpretation
What is important to understand before deciding
What it can contribute
This procedure addresses a specific clinical question. Its usefulness depends on the indication, timing and technique being appropriate for your situation.
What it cannot determine on its own
No test or procedure should be interpreted outside its clinical context. A normal result does not dismiss persistent symptoms, and an abnormal finding does not automatically mean serious disease.
What happens afterwards
Depending on the result, the next step may be discharge, observation, repeat testing, further assessment or treatment. The plan is explained before the episode is considered complete.
Expanded information
Questions we answer during the consultation
The technical information on this page helps you prepare for the consultation. The final decision is made after assessing your circumstances and confirming that the likely benefit outweighs the risk.
Why does the pregnancy week matter so much?
Each test has a window in which it answers a particular question most accurately. Gestational age changes what can be seen, measured and interpreted.
Does a normal result rule out every problem?
No. Each test has a defined scope and limitations. A reassuring result reduces certain risks but cannot guarantee the absence of every possible condition.
What happens if an unexpected finding appears?
It is explained clearly, the need for confirmation is assessed, and the next step may be monitoring, an additional test, referral or specialist counselling.
What it is used for and when
- Routine assessment within the recommended gestational window.
- Guidance on whether NIPT or invasive diagnosis should be considered.
- Early anatomical assessment and dating.
How it is performed
A protocolled ultrasound is combined with clinical information and, where applicable, maternal blood tests. The result is expressed as risk, not certainty.
Preparation
Bring the date of your last menstrual period, previous reports, medication, allergies and obstetric history. Some tests have a specific gestational window.
Tell the team beforehand if pregnancy is possible, you take anticoagulants, have allergies, active infection or a relevant medical condition. Specific instructions take priority over the general information on this page.
After the procedure
The result, limitations and next review are explained. Seek healthcare advice for bleeding, severe pain, fluid loss or a marked reduction in fetal movements.
Risks, limitations and alternatives
False positives and false negatives can occur. A high-risk result must be explained and confirmed by diagnostic testing before irreversible decisions are made.
Clinical judgement and evidence
In obstetrics it is essential to distinguish screening from diagnosis. Screening estimates risk; a high-risk result may need diagnostic confirmation before clinical decisions are made.
Related procedures
Askabide Klinika
Not sure which procedure you need?
You do not need to choose a test on your own. Tell us what concerns you and the team will guide you after assessing your situation.