Mothers’ Pap Screening Is Associated with Daughters’ Uptake of HPV Vaccine

First published online:

| DOI: https://doi.org/10.1363/4119409

Mothers' attitudes toward prevention, and history of abnormal Pap test results or STDs, are strongly linked to whether their daughters receive the human papillomavirus (HPV) vaccine. Adolescent women were more likely to begin receiving the quadrivalent HPV vaccine if their mothers had had a Pap test in the previous three years, had had an abnormal Pap test result or had a history of STDs (odds ratios, 1.1–1.5), according to a study of mother-daughter pairs belonging to a large health care organization in Southern California.1 Daughters of women who had had a recent Pap test also had increased odds of completing the three-dose regimen (1.4), as did those whose mothers had had abnormal test results or had a history of genital or anal warts (1.2 and 1.3, respectively).

Data were drawn from the electronic health records of a managed care organization that serves more than three million Californians. Its members are representative of the general population in Southern California in their ethnic and socioeconomic diversity, and all members have similar health care coverage; HPV vaccinations are available to eligible female members at no additional out-of-pocket cost.

The sample comprised 148,350 mother-daughter pairs; daughters had to be aged 9–17 as of October 2006, the month in which the organization began dispensing the vaccine, and mothers had to have been enrolled for the preceding three years. Vaccine initiation was examined over the subsequent 12 months, and completion of the regimen was examined over the year following receipt of the first dose. Associations between demographic and socioeconomic variables (some of which were derived from data from the U.S. census and the state-subsidized Medi-Cal program), mothers' Pap screening and STD history, and vaccine initiation were examined using analysis of variance and chi-square tests; Pap test screening was considered to be an indicator of women's attitude toward preventive measures. Multivariable logistic regression models assessed the association between mothers' Pap and STD history and daughters' initiation and completion of the vaccine regimen, while adjusting for demographic and socioeconomic characteristics.

Daughters' mean age at the beginning of the study was 13 years. Some 26% were Hispanic, 18% white, 7% black and 4% Asian or Pacific Islander; 44% were of other or unknown race or ethnicity. Daughters who had begun the vaccine regimen were older than those who had not (14 vs. 13), and had been health plan members for longer (10 vs. nine years). Their mothers were more likely to have had a Pap test in the previous three years than were mothers of daughters who had not begun the regimen (82% vs. 76%), and were also more likely to have had an abnormal Pap test result (18% vs. 17%) or genital or anal warts (3% vs. 2%).

In the multivariable analysis, adolescents' vaccine initiation was associated with all four aspects of their mothers' Pap and STD history: having had a Pap test within three years (odds ratio, 1.5), having had an abnormal test result (1.1), having had genital or anal warts (1.2) and having had other STDs (1.1). In addition, mothers' Pap test history was consistently associated with daughters' vaccine initiation regardless of ethnic background (1.3–1.5) or neighborhood education and income levels (1.5–1.6). Mothers' abnormal Pap test results and STD diagnoses were not consistently linked to vaccine initiation across racial, ethnic and socioeconomic groups, and associations were generally modest. Among the 18,275 mother-daughter pairs included in the analysis of the completion of the vaccine regimen, 41% of adolescents completed it within a year of initiation and at the recommended time intervals; another 2% completed the regimen but did not adhere to the recommended timing. Daughters whose mothers had had a Pap test within three years had increased odds of having completed the regimen (odds ratio, 1.4), as did those whose mothers had had abnormal Pap results or a history of genital or anal warts (1.2 and 1.3, respectively). Mothers' Pap test history was also associated with regimen completion for three of the four racial or ethnic groups (1.4–1.6, the exception being among black adolescents) and for every neighborhood education and income level (1.3–1.5). Women's abnormal Pap results and STD diagnoses were not consistently associated with vaccine completion across racial, ethnic and socioeconomic groups. The strongest association was found between mothers' history of having STDs other than genital or anal warts and their daughters' completion of the regimen among those who were of Asian or Pacific Islander background (4.9).

The researchers note several limitations of the study, including their use of neighborhood, rather than individual, socioeconomic measures and their use of Pap test history to indicate mothers' attitude toward preventive measures. Nonetheless, they believe that their use of detailed longitudinal health records minimized potential recall and selection biases, and point out that the diverse member population of the health care organization allowed the examination of associations across ethnically and socioeconomically diverse subgroups. The researchers note that if their findings are confirmed by other studies, public health programs might consider targeting the mothers of adolescent girls in an effort to increase the uptake and completion of the HPV vaccine regimen. Furthermore, they suggest that "mothers' attitudes toward preventive measures are one of the factors determining whether their daughters receive [this] nonmandatory vaccine against HPV infection and comply with its recommended 3-dose regimen."

—J. Thomas

1. Chao C et al., Papanicolaou screening behavior in mothers and human papillomavirus vaccine uptake in adolescent girls, American Journal of Public Health, 2009, 99(6):1137–1142.