Effectiveness and safety of digoxin to induce fetal demise prior to second-trimester abortion

The study was conducted to assess the effectiveness in inducing fetal demise through digoxin injection given 1 day prior to second-trimester pregnancy termination and to evaluate related maternal safety.

A retrospective cohort analysis of 1795 pregnant women between 17 and 24 weeks' gestation who received varying doses of digoxin by transabdominal intrafetal or intra-amniotic injection at the time of laminaria placement was conducted. Fetal heart activity documented by M-mode Doppler sonography on the subsequent day was considered failure. Digoxin dosages started at 1.0 mg for intrafetal and 0.5 mg for intra-amniotic injections and were progressively decreased based on best clinical judgment.

The overall rate of failure to achieve fetal demise was 6.6% (95% CI, 5.5-7.9). Failure rates varied according to route of administration and dosage. There were no failures using a 1.0-mg intrafetal dose, but failures occurred with lower doses. Failure rates were higher with 0.5 mg for intra-amniotic (8.3%) than intrafetal administration (3.6%). There were no adverse maternal events at any of the doses in this study.

Intrafetal digoxin injection at a dose of 1.0 mg is safe and effective for fetal demise prior to pregnancy termination in the second trimester. Significantly lower doses are effective in most cases. Additional doses merit further testing.