Vaccine Education During Pregnancy and Timeliness of Infant Immunization

Pregnant women routinely receive information in support of or opposing infant immunization. We aimed to describe immunization information sources of future mothers' and determine if receiving immunization information is associated with infant immunization timeliness.

We analyzed data from a child cohort born 2009-2010 in New Zealand. Pregnant women (N = 6822) at a median gestation of 39 weeks described sources of information encouraging or discouraging infant immunization. Immunizations received by cohort infants were determined through linkage with the National Immunization Register (n = 6682 of 6853 [98%]). Independent associations of immunization information received with immunization timeliness were described by using adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

Immunization information sources were described by 6182 of 6822 (91%) women. Of these, 2416 (39%) received information encouraging immunization, 846 (14%) received discouraging information, and 565 (9%) received both encouraging and discouraging information. Compared with infants of women who received no immunization information (71% immunized on-time), infants of women who received discouraging information only (57% immunized on time, OR = 0.49, 95% CI 0.38-0.64) or encouraging and discouraging information (61% immunized on time, OR = 0.51, 95% CI 0.42-0.63) were at decreased odds of receiving all immunizations on time. Receipt of encouraging information only was not associated with infant immunization timeliness (73% immunized on time, OR = 1.00, 95% CI 0.87-1.15).

Receipt, during pregnancy, of information against immunization was associated with delayed infant immunization regardless of receipt of information supporting immunization. In contrast, receipt of encouraging information is not associated with infant immunization timeliness.