Recurrent Early Pregnancy Loss With a Normal Karyotype

Actionable vs. non-actionable

• Antiphospholipid antibodies: negative on two occasions 12 weeks apart - this excludes APS by the revised Sapporo/Sydney criteria and is not actionable. Do not treat with heparin/aspirin for 'unexplained' loss.
• Parental karyotypes: normal - no parental translocation; not actionable.
• TSH, prolactin, HbA1c: normal - no endocrine cause identified; not actionable (though subclinical hypothyroidism and PCOS are common associations, neither is present here).
• Uterine septum: a 1-cm fundal septum is the main potentially actionable finding. Its significance depends on whether it is a true septum versus an arcuate uterus; a small septum is of uncertain clinical importance, and the evidence that resecting a septum improves live birth is limited. Do not rush to hysteroscopic resection without discussing the uncertainty.
• Normal 46,XX products of conception: this is uninterpretable because maternal cell contamination can produce a 46,XX result from a chromosomally abnormal pregnancy. It does not exclude a fetal chromosomal cause; it should not be used to conclude the losses were 'maternal.'

Prioritization

1. Clarify the uterine anomaly with 3D ultrasound or MRI to distinguish septum from arcuate; if a true septum is confirmed and she has recurrent loss, hysteroscopic resection can be discussed (with honest counseling about limited evidence).
2. Do not repeat an extensive thrombophilia panel - inherited thrombophilias are not established causes of recurrent first-trimester loss and do not change management.
3. Consider chromosomal microarray on future products of conception (with careful handling to avoid maternal contamination) - this is the highest-yield test if she loses again, because it identifies whether losses are chromosomal.
4. Reassure: with one live birth and three losses, her chance of a subsequent live birth is still substantial (roughly 50–60% in observational series), and most recurrent losses remain unexplained.

Counseling on empiric therapies

• Progesterone: vaginal progesterone has been studied for unexplained recurrent loss; the evidence is mixed and does not clearly show benefit for unexplained recurrent loss (as opposed to a short cervix or threatened loss). It is low-risk, and many clinicians offer it, but she should know it is not proven to prevent recurrence in her situation.
• Low-dose aspirin: not indicated for unexplained recurrent first-trimester loss in the absence of APS; it does not prevent early loss in this setting. It may be considered for preeclampsia prophylaxis in a future pregnancy, but that is a different indication.
• 'Blood thinners' (heparin/LMWH): not indicated - she has no APS and no inherited thrombophilia, and anticoagulation for unexplained recurrent loss has not been shown to improve live birth and carries bleeding risk. This is an important counseling point because patients often request it.
• Uterine septum resection: discuss only if a true septum is confirmed; evidence for benefit is limited, and the procedure carries small risks.

Plan for next pregnancy

1. Preconception: confirm the uterine anomaly with 3D ultrasound/MRI; optimize weight, folic acid 400–800 mcg daily, and review medications.
2. Early ultrasound at 6–7 weeks to confirm viability and document location; serial scans as needed.
3. Low-dose aspirin may be started for preeclampsia risk if other risk factors emerge, but not as a loss-prevention measure.
4. If she loses again: obtain products of conception for chromosomal microarray with careful technique, and consider referral to reproductive immunology or a recurrent-loss specialist if losses continue.
5. Emotional support and realistic expectations: explain that most couples with unexplained recurrent loss eventually have a live birth, and that the absence of a treatable cause is not a failure of care.

Bottom line: avoid unproven anticoagulation and empiric progesterone promises; address the septum question and provide supportive, evidence-based follow-up.