Tetanus and diphtheria toxoids and acellular pertussis vaccine uptake during pregnancy in a metropolitan tertiary care center

Objectives: Tetanus, diphtheria and acellular pertussis (Tdap) vaccine is recommended during each pregnancy, but national uptake is poor. We assessed Tdap uptake in a tertiary referral hospital served by university-affiliated and private obstetrical offices.

Methods: Review of women delivering at Texas Children's Hospital Pavilion for Women, Houston, Texas, during April 2013-June 2014.

Results: 6577 deliveries occurred during the study period. Mean maternal age was 29.8 years (range 13-49); race/ethnicity was 43.6% White, 27% Hispanic, 21% Black, 7.1% Asian, and 1.3% other. 252 were multiple gestations; 229 sets of twins, 21 triplets and 2 quadruplets. 3678 (56%) women received Tdap during pregnancy, 249 (3.8%) postpartum and 100 (1.5%) received Tdap pre-conception only. Tdap uptake during pregnancy increased from 36% in April 2013 to a sustained uptake of greater than 61% since November 2013, with increases noted coincidental with presentations highlighting Tdap maternal immunization recommendations at faculty and staff meetings, and the release of the ACOG "toolkit". When antenatal Tdap vaccine was administered, mean gestation at receipt of Tdap was 31.4 weeks and 95% of vaccinated women received Tdap at the recommended gestation interval of 27-36 weeks, 71.6% during the 28-32 week window believed optimal for placental transport and 98.5% at least 7 days before delivery. Of 19 women with two pregnancies during the study period, four (21%) had Tdap during both. Black women were less likely to receive antenatal Tdap than women of other race/ethnicity (41% versus 60%; P<0.001).

Conclusions: Sustained antenatal Tdap uptake rates exceeding 61% were achieved after strategies to increase awareness of recommendations were introduced and 95% of women were immunized at a gestation optimal for efficient maternal antibody placental transport. Further increases in uptake will require system changes such as best practice alerts in electronic medical records.