Safety of the HPV Bivalent and Quadrivalent Vaccines During Pregnancy

To evaluate the safety of the human papillomavirus (HPV) bivalent and quadrivalent vaccines in pregnancy.

PubMed (1966-August 2010) was searched using the terms human papillomavirus, human papillomavirus vaccine, and pregnancy. References were reviewed for relevant information.

All studies including humans that were published in English with data describing HPV vaccine administration in pregnancy were evaluated.

Two combined analyses of 7 Phase 3 efficacy trials have retrospectively evaluated the safety of unintentional administration of either the bivalent (n = 1786) or quadrivalent (n = 2085) HPV vaccine during pregnancy. In addition, postmarketing pregnancy registry surveillance data (prospective, n = 787; retrospective, n = 76) for the quadrivalent HPV vaccine have been published. However, only 279 pregnancies from the studies and 90 pregnancies from the registry occurred within 30 days of receiving the vaccination. Overall, the vaccine does not appear to be associated with an increased risk of spontaneous abortion, fetal malformations, or adverse pregnancy outcomes beyond that found in the general population. Although the data are limited, neither HPV vaccine appears to be associated with an increased risk of adverse pregnancy outcomes. However, limitations of the data include small patient populations, minimal to no adjustments for factors known to influence pregnancy outcomes or malformations, and the majority of the available pregnancy data are from retrospective analysis of Phase 3 efficacy trials.

Neither HPV vaccine should be routinely administered during pregnancy. If a pregnancy occurs midseries, the remaining vaccines should be given after pregnancy completion. Further studies are required to determine actual risk.