Human Papillomavirus Transmission and Persistence in Pregnant Women and Neonates
Authors: Khayargoli Pranamika , Niyibizi Joseph , Mayrand Marie-Hélène , Audibert François , Monnier Patricia , Brassard Paul , Laporte Louise , Lacaille Julie , Zahreddine Monica , Bédard Marie-Josée , Girard Isabelle , Francoeur Diane , Carceller Ana Maria , Lacroix Jacques , Fraser William , Coutlée François , Trottier Helen ,   HERITAGE Study Group, Trottier Helen , Mayrand Marie-Hélène , Coutlée François , Monnier Patricia , Laporte Louise , Niyibizi Joseph , Zahreddine Monica , Carceller Ana Maria , Brassard Paul , Lacroix Jacques , Francoeur Diane , Bédard Marie-Josée , Girard Isabelle , Audibert François , Fraser William 
Published: May 2023

Importance

The prevalence of human papillomavirus (HPV) infection during pregnancy and its risk of transmission to newborns are not well documented.

Objective

To ascertain the prevalence of HPV in pregnant women, the risk of HPV detection in the placenta and in children at birth, and the probability that HPV detected at birth may persist in newborns.

Design, Setting, and Participants

The Human Papillomavirus Perinatal Transmission and Risk of HPV Persistence Among Children (HERITAGE) study was a prospective cohort study that recruited participants between November 8, 2010, and October 16, 2016. Participant follow-up visits were completed on June 15, 2017. Participants, which included pregnant women of at least 18 years of age and at 14 weeks or earlier of gestation, were recruited from 3 academic hospitals in Montreal, Québec, Canada. Laboratory and statistical analysis were completed on November 15, 2022.

Exposures

HPV DNA testing on self-collected vaginal and placental samples. Among children of mothers positive for HPV, conjunctival, oral, pharyngeal, and genital samples were collected for HPV DNA testing.

Main Outcomes and Measures

Vaginal HPV DNA testing was done on self-collected vaginal samples obtained among pregnant women recruited during their first trimester of pregnancy and in the third trimester for those who had HPV-positive samples in the first trimester. HPV DNA testing was also done on placental samples (swabs and biopsies) collected after birth in all participants. HPV DNA testing among children included conjunctival, oral, pharyngeal, and genital samples collected in children of HPV-positive mothers at birth, 3 months, and 6 months of age.

Results

A total of 1050 pregnant women (mean [SD] age, 31.3 [4.7] years) were included in this study. Prevalence of HPV in pregnant women at recruitment was 40.3% (95% CI, 37.3%-43.3%). Among the 422 HPV-positive women, 280 (66.4%) harbored at least 1 high-risk genotype, and 190 (45.0%) were coinfected with multiple genotypes. HPV was detected in 10.7% of placentas (92 of 860; 95% CI, 8.8%-12.9%) overall, but only 3.9% of biopsies (14 of 361) on the fetal side under the amniotic membrane were positive. Neonatal HPV detection (at birth and/or at 3 months) was 7.2% (95% CI, 5.0%-10.3%) overall, with the most frequent site of infection being the conjunctiva (3.2%; 95% CI, 1.8%-5.6%), followed by the mouth (2.9%; 95% CI, 1.6%-5.2%), the genital area (2.7%; 95% CI, 1.4%-4.9%), and the pharynx (0.8%; 95% CI, 0.2%-2.5%). Importantly, all HPV detected in children at birth cleared before the age of 6 months.

Conclusions and relevance

In this cohort study, vaginal HPV was frequently detected in pregnant women. Perinatal transmission was infrequent, and in this cohort, no infection detected at birth persisted at 6 months. Although HPV was detected in placentas, it remains difficult to differentiate contamination vs true infection.