3.2. Factors associated with susceptibility to rubella
During the study period, 87.9% (19,925), 11.5% (2601) and 0.7%
(148) of pregnant women had one, two or three rubella serology
tests, respectively (corresponding to different pregnancies). Of the
1328 susceptible women, 46% (611) were born in Spain, 9.6% (128)
in China, 5.7% (76) in Morocco, and 4.4% (58) in the Philippines.
Total susceptibility to rubella was 5.9% (1328). There was a variation
in susceptibility by year, ranging from 3.6% in 2008 to 7.6%
in 2011 (p-value < 0.001) (Fig. 1). The highest susceptibility rate
was in the 50% in women aged >30 years. During the
entire study period, women born in Spain were less adherent to
the second dose than immigrant women (52.7% vs. 55.2%) but this
proportion changed in the last year of the study (58.0% vs. 55.3%)
(Fig. 2). After stratification by region of origin, women born in the
rest of Europe, Africa and the Americas had lower adherence than
Spanish women. Asian women were more likely to receive the
second dose, compared to women born in Spain (OR 1.6 (95% CI
1.2–2.2)) (Table 3). Women who gave birth in 2013 were more
likely to receive the second dose compared with those who gave
birth in 2008, OR 1.9 (95% CI 1.2–2.8).
3.4. Immunological response to two doses of MMR vaccine
Around 60% (429/718) of women who received the second MMR
dose returned for the assessment of the antibody response. After