The study included 49 pairs of mothers and newborns.
HPV DNA in maternal genitalia
HPV DNA was detected in 49 (77.8%) of the 63 pregnant women who underwent delivery. The most frequently detected types of HPV DNA were 6/11 (20.7%), 42 (15.9%), 16 (15.9%), 18 (11%), 58 (6.1%) and 31, 35 e 52 (3.7% each). Of these 54.9%, 1.2%, 40.2% and 3.7% were types considered to present a high carcinogenic risk, possible high risk, low risk and HPV DNA present but not classified for viral type respectively (Table ). Genital infections produced by a single type of HPV DNA (38.8%), by two types of HPV DNA (30.6%) and more than two types of HPV DNA (30.6%) were identified.
HPV types in maternal genital sample.
HPV DNA in the placenta
HPV DNA was detected in 12 placentas (24.5%) of the 49 HPV DNA positive pregnant women (HPV DNA+) who underwent delivery. The fetal side of the placenta presented HPV DNA+ in 5 cases (41.7%, n = 5/12), the maternal placental side in 2 cases (16.7%, n = 2/12), while in 5 cases (41.7%, n = 5/12) research for HPV DNA was positive on both sides of the placenta. The viral types identified in the placentas were 6/11 (50%, n = 6/12), 16 (25%, n = 3/12), 18 (16.7%, n = 2/12), 42, 52 and 58 (8.3%, n = 1/12 – each). The type specific HPV concordance among the genital/placental samples was 91.7% (n = 11/12). Seven placentas (58.3%, n = 7/12) presented viral types considered a high carcinogenic risk (types 16, 18, 52 and 58) and 2 placentas presented two different types of HPV DNA (Table ).
Clinical and laboratory history of genital HPV infection during pregnancy and delivery and distribution of HPV types in maternal, newborn and placental samples.
It was observed that seven (58.2%, n = 7/12) cases presented HPV DNA+ for the genital/placental/newborn samples and five (41.7%, n = 5/12) cases presented HPV DNA+ for the genital/placental samples with negative research for HPV DNA in newborns (NB).
HPV DNA in newborns
HPV DNA was identified in eleven NB (22.4%, n = 11/49). Five NB had HPV DNA+ in samples of nasopharyngeal aspirate, six in buccal and body scrapings, and three in arterial cord blood (Table ). The viral types identified were 6/11 (45.5%, n = 5/11), 42 (18.2%, n = 2/11), 52 (18.2%, n = 2/11), 18 and 59 (9.1%, n = 1/11 – each). Four NB (36.4%, n = 4/11) presented viral types considered a high carcinogenic risk (types 18, 52 and 59). In one NB two types of HPV DNA were detected (types 6/11 and 52).
Among the eleven cases of NB HPV DNA+, seven (63.6%, n = 7/11) presented HPV DNA+ for the genital/placental/NB samples. Six of these cases (85.7%, n = 6/7) were in concordance as to the type-specific HPV among the placental/NB samples and five cases (71.4%, n = 5/7) presented concordance as to the type specific HPV among the genital/placental/NB samples, suggesting the transplacental transmission of the virus (10.2%, n = 5/49).
No physical abnormalities or genital warts were observed in the 49 newborns.
Among the 11 cases of NB HPV DNA+ (vertical transmission), four (36.4%, n = 4/11) did not present transplacental infection due to virus (Table ). Of these, one case presented type specific HPV concordance among the genital/arterial cord blood samples (HPV type 52) suggesting the possibility of transplacental transmission. Among the three other cases, two had type specific HPV concordance among the genital/NB samples (HPV types 11 and 42).
On the other hand, five NB (41.7%, n = 5/12) were negative for HPV DNA research, while in their respective placentas HPV DNA+ was shown (Table ). The HPV identified were types 16 (40%, n = 2/5), 6/11, 18 and 58 (20%, n = 1/5 – each). Four NB (80%, n = 4/5) presented viral types considered a high carcinogenic risk (types 16, 18, 58). The concordance of type specific HPV observed among the genital/placental samples was 100% (n = 5/5).
HPV DNA in arterial cord blood
Studying the arterial blood from the umbilical cords of NB (Table ), 3 cases (6.1%, n = 3/49) HPV DNA+ for viral types 6/11, 18 and 52 were observed. In 2 clinical cases there was concordance of type specific HPV among the genital/placental/arterial cord blood samples, and in the other case, concordance of type specific HPV among the genital/arterial cord blood was observed. The latter case mentioned, which corresponds to the same case mentioned above, was considered transplacental transmission (hematogenic, directly through the placenta, without any infection in the latter). Of the 3 cases studied, two (66.7%) had HPV DNA types 18 and 52 considered a high carcinogenic risk.
HPV DNA in maternal peripheral blood
Three (6.1%, n = 3/49) parturients had HPV DNA in their peripheral blood (Table ). In two cases HPV DNA that was considered a high carcinogenic risk (types 16 and 58) was detected. There was 66.7% (n = 2/3) concordance of type specific HPV among the maternal genital/peripheral blood samples. In all three cases no HPV DNA was identified in the respective placentas and NB.
Statistical analysis showed a significant association between placental HPV infection and the epidemiological variable history of immunodepression (HIV, p = 0.011), as observed in table and .
HPV status of the placenta and maternal factors.
HPV status of the placental and delivery factors.
In the group of pregnant women negative for genital HPV DNA (n = 14/63), it was observed that all samples, both of maternal peripheral blood and those of nasopharyngeal aspirate, buccal and bodily scrapings and arterial cord blood and those of placental biopsies and scrapings presented negative results for HPV DNA research.
HPV detection and typing methods
Evaluating the HPV DNA detection and typing methods, it was observed that the multiplex PCR methodology identified HPV DNA in 41 pregnant women (83.7%, n = 41/49), in 31 pregnant women (75.6%, n = 31/41) only a single type of HPV DNA was identified, and two or more types of HPV in 10 pregnant women (24.4%, n = 10/41). The nested multiplex PCR method (although it was used to identify and type 9 types of HPV shown as the most prevalent in the city of Caxias do Sul) identified HPV DNA in 43 pregnant women (87.8%, n = 43/49), only a single type of HPV DNA in 28 pregnant women (83.7%, n = 28/43), and two or more types of HPV in 15 pregnant women (83.7%, n = 15/43). Together the multiplex PCR and nested multiplex PCR methods identified HPV DNA in 49 pregnant women (100%, n = 49/49), only a single type of HPV DNA in 19 pregnant women (38.8%, n = 19/49) and two or more types of HPV in 30 pregnant women (61.2%, n = 30/49).
The multiplex PCR method identified HPV DNA in only two newborns (18.2%, n = 2/11), while the nested multiplex PCR method identified it in 9 newborns (81.8%, n = 9/11).
In the placentas, multiplex PCR identified HPV DNA in only a single one (83.7%, n = 1/12), while the nested multiplex PCR method identified HPV in 12 cases (100%, n = 12/12).