Objective Standards of care regarding obstetric management of life-threatening anomalies are not defined. It is hypothesised that physicians' management of these pregnancies is variable and influenced by demographic factors. Design A questionnaire was mailed to members of the Society of Maternal–Fetal Medicine with valid US addresses assessing obstetric management of both ‘uniformly lethal’ (eg, anencephaly, renal agenesis) and ‘uniformly severe, commonly lethal’ (eg, trisomy 13 and 18) anomalies. Respondents were asked to answer as if not limited by state/institutional restrictions. Fisher's (...) exact or χ2 tests were used as appropriate and correction made for multiple comparisons in analyses that were not prespecified. Results The response rate was 36% (732/2038). Nearly 100% of respondents discuss termination for both uniformly and commonly lethal anomalies. In continuing pregnancies, with patient request for obstetric non-intervention 99% of providers would comply for either uniformly or commonly lethal anomalies. The majority ‘encourage’ such management, but some were non-directive or discouraged this management. In continuing pregnancies, with patient request for full obstetric intervention the majority of respondents was willing to comply for both uniformly (71%) and commonly (82%) lethal anomalies. While most practitioners ‘discouraged’ full intervention, some were non-directive or encouraged this management. Demographics and severity of anomaly influenced counselling. Conclusion Discrepancies exist regarding the management of life-threatening fetal anomalies. Patients may be offered different options based on practitioner demographics. The majority of physicians comply with patient wishes. Differences were noted when comparing the management of lethal with that of severe commonly lethal anomalies, suggesting that practitioners make a distinction when counselling patients. (shrink)