Fetal endoxin and pregnancy complication.

Digoxin-like substances (endoxin) are found in increasing concentrations in serum and urine with advancing pregnancy. Some high-risk pregnant women with hypertension and/or in premature labor have increased levels of endoxin. Both nifedipine and antidigoxin serum are proposed as specific therapy in abnormal pregnancies with high levels of endoxin. Urinary endoxin levels may indicate otherwise unsuspected high-risk pregnancies.