Is testing after recurrent miscarriage safe during pregnancy?

What does the evidence say about testing after recurrent miscarriage during pregnancy?

1. ASRM’s 2026 committee opinion defines recurrent pregnancy loss as two or more losses, excluding confirmed molar and ectopic pregnancies. A positive urine or blood hCG result can document a pregnancy; ultrasound or tissue confirmation is not required for every loss to count. 1
2. ACOG recommends a history, examination, and evaluation after two miscarriages. Potential contributors include chromosome rearrangements, uterine abnormalities, antiphospholipid syndrome, and selected endocrine conditions, but many evaluations remain unexplained. 2
3. The updated ASRM approach prioritizes chromosome analysis of miscarriage tissue when feasible and evaluation of uterine anatomy. Parental chromosome testing and medical laboratory tests depend on tissue findings, history, symptoms, and clinical indications. 1
4. The ESHRE recurrent-loss guideline emphasizes that much investigation and intervention evidence is low or very low certainty. A test being commercially available does not establish that it improves the chance of a live birth or should be ordered routinely. 3
5. A Cochrane review considered aspirin and heparin in the specific setting of persistent antiphospholipid antibodies and repeated loss. Its low-certainty findings should not be extended to everyone with miscarriage or used to justify an unselected clotting panel. 4

Is testing after recurrent miscarriage safe in each trimester?

• First trimester. Before another pregnancy, collect dates, pregnancy-test results, ultrasound reports, tissue results, prior births, and relevant family or clotting history. Early biochemical losses can matter even when no embryo was seen on ultrasound.
• Second trimester. If pregnant during evaluation, ask which tests remain useful now and which need different timing. The team should separate an investigation of earlier losses from assessment of current bleeding, pain, or uncertain pregnancy location.
• Third trimester. After results, request an explanation of what each finding changes and what remains unexplained. A future pregnancy plan can include early access, emotional support, and appropriate surveillance without promising that an extensive panel will identify a cause.