Investigation of factors associated with spontaneous preterm birth in pregnant women living with HIV.

OBJECTIVE: To investigate factors contributing to preterm birth (PTB), including cART use and clinical and social determinants of health, in women living with HIV (WLWH) from British Columbia, Canada. DESIGN: Retrospective observational cohort. METHODS: We investigated the effect of cART use and other clinical and demographic factors on spontaneous PTB (sPTB) rates (<37 weeks gestational age) among 631 singleton pregnancies between 1997 and 2018. Exposure to cART was modelled in comparison to no exposure, exposure in the first trimester, and between regimens. Differences in sPTB risk were estimated using time-dependent Cox's proportional hazards models. RESULTS: Overall, the sPTB rate was 16%. Cumulative cART use was associated with lower risk of PTB (Wald test P = 0.02; hazard ratio = 0.98, 95% CI = 0.96-0.99) and specific cART regimens were not associated with increased risk of sPTB. Exposure in the first trimester was not associated with sPTB and for each week of cART exposure, the risk of sPTB decreased by 2%. In a multivariable model, HIV viral load and substance use remained associated with risk of sPTB, but not cART exposure. CONCLUSION: The sPTB rate among pregnant WLWH was more than three times higher than in the general population. However, sPTB was not related specifically to use of cART; in fact, cART appeared to reduce the risk of sPTB. Uncontrolled HIV replication and substance use were associated with increased risk of sPTB among pregnant WLWH. This emphasizes the important role of prenatal care, access to cART, and smoking cessation and harm reduction to reduce the risk of sPTB in WLWH.

Understanding Men's Perceptions of Human Papillomavirus and Cervical Cancer Screening in Kampala, Uganda.

PURPOSE: This preliminary study explores Ugandan men's knowledge and attitudes about human papillomavirus (HPV), cervical cancer, and screening. METHODS: A local physician led an education session about cervical cancer for 62 men in Kisenyi, Kampala in Uganda. Trained nurse midwives administered surveys to assess knowledge and attitudes before and after the education session. RESULTS: From the pre-education survey, only 24.6% of men had heard of HPV previously, and 59% of men had heard of cervical cancer. Posteducation, 54.5% of men believed only women could be infected with HPV and 32.7% of men believed antibiotics could cure HPV. Despite their limited knowledge, 98.2% of men stated they would support their partners to receive screening for cervical cancer, and 100% of men surveyed stated they would encourage their daughter to get the HPV vaccine if available. CONCLUSIONS: Knowledge of HPV and cervical cancer among Ugandan men is low. Even after targeted education, confusion remained about disease transmission and treatment. Ongoing education programs geared toward men and interventions to encourage spousal communication about reproductive health and shared decision making may improve awareness of cervical cancer prevention strategies.

Human Immunodeficiency Virus Viral Load Rebound Near Delivery in Previously Suppressed, Combination Antiretroviral Therapy-Treated Pregnant Women.

OBJECTIVE: To assess the stability of human immunodeficiency virus (HIV) viral load suppression within 1 month before birth in pregnant women receiving antenatal combination antiretroviral therapy (CART). METHODS: This is a retrospective cohort study of a Canadian provincial perinatal HIV database from 1997 to 2015. Inclusion criteria were live birth and CART received for at least 4 weeks. Viral load rebound, defined as viral load greater than 50 copies/mL (or greater than 400 copies/mL for 1997-1998) and measured within 1 month before delivery, was identified in women who had at least one previous undetectable viral load during pregnancy. Logistic regressions were conducted to identify the risk factors for viral load rebound. RESULTS: Among the 470 women in the database, 318 met inclusion criteria. Viral load rebound was experienced by 19 women (6.0%, 95% CI 3.7-9.3%) with a mean log10 viral load near delivery of 2.71 copies/mL (=513 copies/mL). Six (32%) had a viral load above 1,000 copies/mL. The rebound was detected within 1 day before delivery in 50% of the women. Aboriginal ethnicity, cocaine use, and hepatitis C virus polymerase chain reaction positivity were significantly associated with viral load rebound. There were no HIV vertical transmissions. CONCLUSION: Even women attending for HIV care and achieving viral suppression in pregnancy can experience viral load rebound predelivery.

High Diversity and Variability in the Vaginal Microbiome in Women following Preterm Premature Rupture of Membranes (PPROM): A Prospective Cohort Study.

OBJECTIVE: To characterize the vaginal microbiota of women following preterm premature rupture of membranes (PPROM), and determine if microbiome composition predicts latency duration and perinatal outcomes. DESIGN: A prospective cohort study. SETTING: Canada. POPULATION: Women with PPROM between 24+0 and 33+6 weeks gestational age (GA). METHODS: Microbiome profiles, based on pyrosequencing of the cpn60 universal target, were generated from vaginal samples at time of presentation with PPROM, weekly thereafter, and at delivery. MAIN OUTCOME MEASURES: Vaginal microbiome composition, latency duration, gestational age at delivery, perinatal outcomes. RESULTS: Microbiome profiles were generated from 70 samples from 36 women. Mean GA at PPROM was 28.8 wk (mean latency 2.7 wk). Microbiome profiles were highly diverse but sequences representing Megasphaera type 1 and Prevotella spp. were detected in all vaginal samples. Only 13/70 samples were dominated by Lactobacillus spp. Microbiome profiles at the time of membrane rupture did not cluster by gestational age at PPROM, latency duration, presence of chorioamnionitis or by infant outcomes. Mycoplasma and/or Ureaplasma were detected by PCR in 81% (29/36) of women, and these women had significantly lower GA at delivery and correspondingly lower birth weight infants than Mycoplasma and/or Ureaplasma negative women. CONCLUSION: Women with PPROM had mixed, abnormal vaginal microbiota but the microbiome profile at PPROM did not correlate with latency duration. Prevotella spp. and Megasphaera type I were ubiquitous. The presence of Mollicutes in the vaginal microbiome was associated with lower GA at delivery. The microbiome was remarkably unstable during the latency period.

Evidence of Subclinical mtDNA Alterations in HIV-Infected Pregnant Women Receiving Combination Antiretroviral Therapy Compared to HIV-Negative Pregnant Women.

INTRODUCTION: Combination antiretroviral therapy (cART) can effectively prevent vertical transmission of HIV but there is potential risk of adverse maternal, foetal or infant effects. Specifically, the effect of cART use during pregnancy on mitochondrial DNA (mtDNA) content in HIV-positive (HIV+) women is unclear. We sought to characterize subclinical alterations in peripheral blood mtDNA levels in cART-treated HIV+ women during pregnancy and the postpartum period. METHODS: This prospective longitudinal observational cohort study enrolled both HIV+ and HIV-negative (HIV-) pregnant women. Clinical data and blood samples were collected at three time points in pregnancy (13-<23 weeks, 23-<30 weeks, 30-40 weeks), and at delivery and six weeks post-partum in HIV+ women. Peripheral blood mtDNA to nuclear DNA (nDNA) ratio was measured by qPCR. RESULTS: Over a four year period, 63 HIV+ and 42 HIV- women were enrolled. HIV+ women showed significantly lower mtDNA/nDNA ratios compared to HIV- women during pregnancy (p = 0.003), after controlling for platelet count and repeated measurements using a multivariable mixed-effects model. Ethnicity, gestational age (GA) and substance use were also significantly associated with mtDNA/nDNA ratio (p≤0.02). Among HIV+ women, higher CD4 nadir was associated with higher mtDNA/nDNA ratios (p<0.0001), and these ratio were significantly lower during pregnancy compared to the postpartum period (p<0.0001). CONCLUSIONS: In the context of this study, it was not possible to distinguish between mtDNA effects related to HIV infection versus cART therapy. Nevertheless, while mtDNA levels were relatively stable over time in both groups during pregnancy, they were significantly lower in HIV+ women compared to HIV- women. Although no immediate clinical impact was observed on maternal or infant health, lower maternal mtDNA levels may exert long-term effects on women and children and remain a concern. Improved knowledge of such subclinical alterations is another step toward optimizing the safety and efficacy of cART regimens during pregnancy.

A Study of the Vaginal Microbiome in Healthy Canadian Women Utilizing cpn60-Based Molecular Profiling Reveals Distinct Gardnerella Subgroup Community State Types.

The vaginal microbiota is important in women's reproductive and overall health. However, the relationships between the structure, function and dynamics of this complex microbial community and health outcomes remain elusive. The objective of this study was to determine the phylogenetic range and abundance of prokaryotes in the vaginal microbiota of healthy, non-pregnant, ethnically diverse, reproductive-aged Canadian women. Socio-demographic, behavioural and clinical data were collected and vaginal swabs were analyzed from 310 women. Detailed profiles of their vaginal microbiomes were generated by pyrosequencing of the chaperonin-60 universal target. Six community state types (CST) were delineated by hierarchical clustering, including three Lactobacillus-dominated CST (L. crispatus, L. iners, L. jensenii), two Gardnerella-dominated (subgroups A and C) and an "intermediate" CST which included a small number of women with microbiomes dominated by seven other species or with no dominant species but minority populations of Streptococcus, Staphylococcus, Peptoniphilus, E. coli and various Proteobacteria in co-dominant communities. The striking correspondence between Nugent score and deep sequencing CST continues to reinforce the basic premise provided by the simpler Gram stain method, while additional analyses reveal detailed cpn60-based phylogeny and estimated abundance in microbial communities from vaginal samples. Ethnicity was the only demographic or clinical characteristic predicting CST, with differences in Asian and White women (p = 0.05). In conclusion, this study confirms previous work describing four cpn60-based subgroups of Gardnerella, revealing previously undescribed CST. The data describe the range of bacterial communities seen in Canadian women presenting with no specific vaginal health concerns, and provides an important baseline for future investigations of clinically important cohorts.

Characterization of the vaginal microbiota of healthy Canadian women through the menstrual cycle.

BACKGROUND: The vaginal microbial community plays a vital role in maintaining women's health. Understanding the precise bacterial composition is challenging because of the diverse and difficult-to-culture nature of many bacterial constituents, necessitating culture-independent methodology. During a natural menstrual cycle, physiological changes could have an impact on bacterial growth, colonization, and community structure. The objective of this study was to assess the stability of the vaginal microbiome of healthy Canadian women throughout a menstrual cycle by using cpn60-based microbiota analysis. Vaginal swabs from 27 naturally cycling reproductive-age women were collected weekly through a single menstrual cycle. Polymerase chain reaction (PCR) was performed to amplify the universal target region of the cpn60 gene and generate amplicons representative of the microbial community. Amplicons were pyrosequenced, assembled into operational taxonomic units, and analyzed. Samples were also assayed for total 16S rRNA gene content and Gardnerella vaginalis by quantitative PCR and screened for the presence of Mollicutes by using family and genus-specific PCR. RESULTS: Overall, the vaginal microbiome of most women remained relatively stable throughout the menstrual cycle, with little variation in diversity and only modest fluctuations in species richness. Microbiomes between women were more different than were those collected consecutively from individual women. Clustering of microbial profiles revealed the expected groupings dominated by Lactobacillus crispatus, Lactobacillus iners, and Lactobacillus jensenii. Interestingly, two additional clusters were dominated by either Bifidobacterium breve or a heterogeneous mixture of nonlactobacilli. Direct G. vaginalis quantification correlated strongly with its pyrosequencing-read abundance, and Mollicutes, including Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum, were detected in most samples. CONCLUSIONS: Our cpn60-based investigation of the vaginal microbiome demonstrated that in healthy women most vaginal microbiomes remained stable through their menstrual cycle. Of interest in these findings was the presence of Bifidobacteriales beyond just Gardnerella species. Bifidobacteriales are frequently underrepresented in 16S rRNA gene-based studies, and their detection by cpn60-based investigation suggests that their significance in the vaginal community may be underappreciated.

Hepatitis C infection among pregnant women in British Columbia: reported prevalence and critical appraisal of current prenatal screening methods.

BACKGROUND: Despite the fact that hepatitis C virus (HCV) is a relatively common infection in Canada, particularly in British Columbia (BC), there is a paucity of information on actual HCV prevalence in pregnant women. At present, pregnant women are only screened if they fit risk criteria, which may result in under-identification of HCV in this population. The purpose of this study was to determine the overall prevalence rate, age and geographic distribution of reported HCV infection among pregnant women in BC, and compare results to a previously conducted anonymous seroprevalence survey. METHODS: Reported HCV prevalence was determined through a confidential database linkage of all prenatal screening results at the Canadian Blood Services (CBS) with all HCV test results at the Provincial Laboratory, from May 2000 to Oct 2002. Data were stratified by age group and geographic location, and subsequently compared to an anonymous prenatal seroprevalence survey conducted in 1994. RESULTS: The overall HCV prevalence rate was 50.3/10,000 (95% CI 46.3-54.6), or 0.5% of the cohort. Prevalence was highest in the northern BC region (66.2/10,000, 95% CI 51.4-85.3) and lowest in the populous suburban region southwest of Vancouver (38.0/10,000, 95% CI 32.3-44.8). Of note, the rate of reported HCV among pregnant women was significantly lower than the anonymous seroprevalence rate: 50.3/10,000 vs. 91.3/10,000 (p < 0.0001). CONCLUSION: Rates of reported HCV among pregnant women were approximately 50% lower than the rates determined by the anonymous seroprevalence survey. Further research is needed to determine the relative merits of the current selective screening policy versus universal prenatal HCV screening in pregnancy.

Inadequacy of plasma acyclovir levels at delivery in patients with genital herpes receiving oral acyclovir suppressive therapy in late pregnancy.

OBJECTIVE: Acyclovir therapy in late pregnancy among women with recurrent genital herpes is effective in decreasing genital lesion frequency and subclinical viral shedding rates at delivery, thereby decreasing the need for Caesarean section. Despite good adherence and increased dosing schedules, breakthrough lesions and viral shedding are still observed in some women at or near delivery. Anecdotal evidence suggests that low levels of herpes simplex virus replication at delivery may result in transmission to the neonate. Therefore, defining optimal acyclovir dosing during labour and delivery is warranted. Our objectives were to determine actual maternal and fetal acyclovir levels at delivery, and explore associations between acyclovir levels, duration of labour, and time since last acyclovir dose. METHODS: Twenty-seven patients were prescribed oral acyclovir 400 mg three times daily from 36 weeks' gestation. Cord blood (venous and arterial) and maternal venous blood samples were collected at delivery, and acyclovir levels measured using capillary electrophoresis. Correlations between duration of labour, and time since last acyclovir dose with acyclovir blood levels were calculated. RESULTS: Acyclovir levels were below the published mean steady-state trough value (180 ng/mL) in 52% of venous cord samples, 55% of arterial cord samples, and 36% of maternal samples. There was a significant inverse correlation between the time since last dose and venous cord levels (rs19 = -0.57, P < 0.015), arterial cord levels (rs16 = -0.63, P < 0.01), and maternal acyclovir levels (r10 = -0.69, P < 0.03). CONCLUSION: Oral dosing of acyclovir in women in late pregnancy may result in insufficient levels at delivery to prevent viral shedding. Alternative approaches that incorporate acyclovir dosing through labour, either through oral or intravenous administration, should be evaluated to assess effects on viral shedding.

Hematological changes associated with egg production: direct evidence for changes in erythropoiesis but a lack of resource dependence?

Reductions in hematological parameters among laying birds are well reported, but the cause of this anemia is not known. We tested specific predictions generated from several, non-mutually exclusive hypotheses for mechanisms underlying reproductive anemia associated with egg production (hemodilution, transient suppression of erythropoiesis, resource dependence) in relation to (1) the time-course of development and recovery from anemia, (2) changes in specific hematological traits, and (3) the effect of diet quality, in female zebra finches (Taeniopygia guttata). Female zebra finches showed marked decreases in hematocrit (approximately 6%), red blood cell counts ( approximately 8%), and plasma hemoglobin concentration (approximately 9%) during egg production, even on a high-quality ad libitum diet, consistent with an effect of hemodilution associated with yolk precursor production. However, our results provide strong support for the hypothesis that erythropoiesis is transiently suppressed during egg-laying and that the recovery from anemia is relatively long-lasting, extending through incubation and hatching periods. Decreased hematocrit, red blood cell counts, and hemoglobin concentration did not recover at clutch completion, but showed evidence of recovery to baseline pre-breeding levels at hatching. More importantly, there was significant time-dependent variation in the proportion of reticulocytes, which increased at clutch completion but peaked at hatching 10-12 days after clutch completion, and in mean red blood cell volume, which showed a significant increase at clutch completion; consistent with enhanced production and release of larger immature cells into the circulation following suppression of erythropoiesis. Finally, we found no evidence for resource dependence of anemia associated with egg production in relation to diet quality, i.e. exogenous lipid and protein resources available to the laying female. This study demonstrates that transient suppression of erythropoiesis and, subsequently, increased reticulocytosis, are key components of reproductive anemia in egg-laying females.

Hematological changes associated with egg production: estrogen dependence and repeatability.

The 'cost of reproduction' (i.e. the trade-off between current reproduction and future fecundity and/or survival) is a central concept in life history theory, yet we still know very little about the physiological mechanisms underlying such costs. Recently it has been recognized that reproduction itself or the regulatory (hormonal) mechanisms underlying reproduction might result in 'costs' (cf. resource-allocation based mechanisms). As one example, it has been suggested that the decrease in hematocrit observed during egg production in birds might be due to antagonistic pleiotropic effects of estrogens. This could generate costs of reproduction by reducing oxygen-carrying capacity during subsequent aerobically demanding stages such as chick-provisioning. Here we show that the reduction in hematocrit during egg-laying is dependent on receptor-mediated actions of endogenous estrogens: blocking estrogen receptors using the anti-estrogen tamoxifen reduces the decrease in hematocrit during egg production in female zebra finches (Taeniopygia guttata) such that hematocrit at the 1-egg stage is not significantly different than pre-breeding, baseline values. We also show that both pre-breeding hematocrit and the decrease in hematocrit associated with egg production are repeatable, and that females with the highest pre-breeding hematocrit values tend to show the largest decreases in hematocrit during egg production. We suggest that hematological changes during egg production are a good candidate mechanism for a regulatory-network based trade-off involving antagonistic pleiotropic effects of estrogens, which otherwise have essential reproductive functions.

Experimental (antiestrogen-mediated) reduction in egg size negatively affects offspring growth and survival.

The relationship between egg size and offspring phenotype is critical to our understanding of the selective pressures acting on the key reproductive life-history traits of egg size and number. Yet there is surprisingly little empirical evidence to support a strong, positive relationship between egg size and offspring quality (i.e., offspring growth, condition, and survival) in birds, in part because of confounding effects of parental quality and the lack of experimental techniques for directly manipulating avian egg size independently of maternal condition. Previously, we showed that treatment of laying female zebra finches (Taeniopygia guttata) with the antiestrogen tamoxifen can decrease egg size by ca. 8% but that this reduction in egg size had few effects on offspring mass and size at fledging. Here, we extend the use of this technique to induce larger decreases in egg size (up to 50% in individual females) and show that a reduction in egg size of ca. 18% is associated with decreased embryo viability, increased hatchling mortality, and lower posthatching offspring survival. Furthermore, we show that although hatchlings from eggs reduced in size by ca. 9% can survive to fledging, these chicks show slower initial growth during the linear growth phase (5-10 d of age), fledge at lower masses than chicks from control eggs, and show postfledging compensatory growth. Our results provide empirical support for significant effects of egg size on offspring quality and further suggest that among individual females there is a minimum egg size required to maintain embryo viability and offspring quality.