Miscarriage investigations: Questions About the Tests and Their Limits

Investigations after miscarriage are intended to find information that can explain a loss or guide future care. Those are related but different purposes. Before a test, ask which purpose it serves and how each possible result would change the plan. A larger number of tests does not necessarily produce a clearer answer.

Start with the question the clinician is investigating

The pattern and timing of losses, previous results and medical history help determine the assessment. If you have not yet discussed referral, the recurrent miscarriage assessment guide explains why different services use different thresholds. This article focuses on understanding the tests once that conversation has started.

Bring copies of previous reports if possible. Ask the clinician to identify information that is already available, anything that needs repeating and tests that are not indicated. It can help to write down the question next to each test name rather than leaving with an unexplained list of abbreviations.

Distinguish pregnancy tissue testing from parental testing

Chromosome testing of pregnancy tissue may help explain a miscarriage. Testing the parents’ chromosomes answers a different question and may be offered when a tissue result suggests an inherited rearrangement or when tissue testing is unavailable. A result from one pregnancy does not automatically explain every previous loss.

Ask whether a suitable sample exists, what consent is needed and what happens if the laboratory cannot obtain a result. If testing finds a change, request an explanation of whether it appears to have happened by chance or could have implications for relatives or future pregnancies. Genetic counselling may help with those questions.

Understand blood tests and uterine assessment

Assessment can include imaging of the uterine cavity and selected blood tests. For example, testing for antiphospholipid syndrome is interpreted alongside pregnancy and clotting history; a diagnosis cannot be made from an isolated antibody result. Confirmation generally requires persistent positive results at least 12 weeks apart.

Thyroid testing may also be considered. Recommendations differ about which thyroid tests to offer and to whom, so ask what question your own panel addresses. If imaging shows a finding, ask whether it is thought to explain the losses and whether treating it is known to improve outcomes. An abnormality does not automatically mean surgery is useful.

Question additional panels and plan the results visit

Routine inherited thrombophilia panels and broad immune testing, including natural killer cell testing, are not established answers for everyone with recurrent miscarriage. Ask what evidence supports an extra test in your circumstances, particularly if it comes with a costly treatment package.

Before leaving, agree when results should arrive, who will explain them and whether trying to conceive should wait for a particular result. The trying again guide can help you prepare that discussion. If results do not identify a cause, request a plan for continuing support and early contact in a future pregnancy rather than assuming the investigation has nothing further to offer.