Immunity to diphtheria and tetanus in inner-city women of childbearing age.

This study was conducted to determine immunity to diphtheria and tetanus in 232 inner-city women experiencing a recent birth. Forty-three (18.5 percent) of the women had levels of diphtheria antitoxin below the protective level (less than 0.01 unit/ml), whereas only 10 (4.3 percent) had insufficient levels of tetanus antitoxin. The percent of women susceptible increased with age, with 33 percent and 25 percent of women over the age of 30 years susceptible to diphtheria and tetanus, respectively.