Maternal microbial factors that affect the fetus and subsequent offspring

The maternal microbiome has emerged as an important area of investigation. While birth is a critical timepoint for initial colonization of the newborn, the fetus resides in the womb surrounded by multiple unique colonized niches. The maternal microbiome has recently been shown to be associated with several morbidities in offspring. Understanding the multiple bacterial niches within the pregnant woman and how they interact with the fetus in-utero can lead to novel therapies to improve the health of offspring. In this review, we provide an overview of the available literature on normal bacterial colonization within the individual niches of the pregnant woman and the known associations with outcomes in offspring, including a discussion of the controversy of in-utero colonization.     

Analysis of lactobacillus products for phages and bacteriocins that inhibit vaginal lactobacilli

Objective: Bacterial vaginosis is associated with an unexplained loss of vaginal lactobacilli. Previously, we have identified certain vaginal lactobacilli-released phages that can inhibit in vitro other vaginal lactobacilli. However, there is no apparent route for phages to be transmitted among women. The purpose of this study was to identify whether certain Lactobacillus products commonly used by women release phages or bacteriocins that can inhibit vaginal lactobacilli.Methods: From 26 Lactobacillus products (2 acidophilus milks, 20 yogurts, 3 Lactobacillus pills, and 1 vaginal douche mix), lactobacilli were isolated with Rogosa SL agar (Difco, Detroit, MI). From these lactobacilli, phages and bacteriocins were induced with mitomycin C and tested against a collection of vaginal Lactobacillus strains.Results: From the 26 products, 43 Lactobacillus strains were isolated. Strains from 11 yogurts released phages, among which 7 inhibited vaginal lactobacilli. Eleven strains released bacteriocins that inhibited vaginal lactobacilli. While about one-half of the vaginal strains were lysed by bacteriocins, less than 20% were lysed by phages.Conclusions: Some vaginal lactobacilli were inhibited in vitro by phages or bacteriocins released from Lactobacillus products used by women, implying that vaginal lactobacilli may be reduced naturally due to phages or bacteriocins from the environment.     

细菌性阴道病患者与健康妇女阴道乳杆菌生态学特征的比较

目的:观察健康妇女与细菌性阴道病患者阴道内乳杆菌属内各种乳杆菌在阴道中分布的差异。方法:利用微生态学研究方法,调查45例健康妇女和40例细菌性阴道病患者阴道乳杆菌的分布,鉴定阴道内乳杆菌,比较阴道乳杆菌产生过氧化氢的能力。结果:健康妇女阴道内乳杆菌检出率和平均活菌数量对数值明显高于细菌性阴道病患者(P<0.01),健康妇女阴道内优势乳杆菌是嗜酸乳杆菌(35%,7·68±1.41)、德氏乳杆菌(7·5%,8.06±0.83)和乳酸乳杆菌(7·5%,8.07±1·51),其大多数产生H2O2能力较强;健康妇女阴道内产H2O2乳杆菌的分离率明显高于细菌性阴道病患者(P<0.01)。结论:H2O2阳性的乳杆菌是健康妇女阴道乳杆菌的重要成员,在防治细菌性阴道病发生中起重要作用。     

Parallel detection of lactobacillus and bacterial vaginosis-associated bacterial DNA in the chorioamnion and vagina of pregnant women at term

Background: The majority of early preterm births are associated with intrauterine infections, which are thought to occur when microbes traffic into the uterus from the lower genital tract and seed the placenta. Bacterial vaginosis (BV) is associated with heterogeneous bacterial communities in the vagina and is linked to preterm birth. The extent to which trafficking into the uterus of normal and BV-associated vaginal bacteria occurs is unknown. The study objective was to characterize in parallel the distribution and quantities of bacteria in the vagina, uterus, and placental compartments.

Methods: Pregnant women at term (≥37 weeks) presenting for delivery were recruited prospectively. Swabs were collected in parallel from the vagina, chorioamnion. Choriodecidual swabs were collected if a cesarean section was performed. Samples were analyzed by culture, broad-range 16S rRNA gene PCR, and bacterial species-specific quantitative PCR (qPCR) for DNA from Lactobacillus and a panel of BV-associated bacteria. Results were correlated with placental histopathology.

Results: Of the 23 women enrolled, 15 were delivered by cesarean section (N?=?10 without labor; N?=?5 in labor) and eight were delivered vaginally. BV was diagnosed in two women not in labor. Placental histopathology identified chorioamnionitis or funisitis in six cases [1/10 (10%) not in labor; 5/13 (38%) in labor]. Among non-laboring women, broad-range 16S qPCR detected bacteria in the chorioamnion and the choriodecidua (4/10; 40%). Among laboring women, Lactobacillus species were frequently detected in the chorioamnion by qPCR (4/13; 31%). In one case, mild chorioamnionitis was associated with qPCR detection of similar microbes in the chorioamnion and vagina (e.g. Leptotrichia/Sneathia, Megasphaera), along a quantitative gradient.

Conclusions: Microbial trafficking of lactobacilli and fastidious bacteria into the chorioamniotic membranes and choriodecidua occurs at term in normal pregnancies. In one case, we demonstrated a quantitative gradient between multiple bacterial species in the lower genital tract and placenta. Not all bacterial colonization is associated with placental inflammation and clinical sequelae. Further studies of the role of placental colonization with Lactobacillus in normal pregnancy and fastidious bacteria in chorioamnionitis may improve prevention and treatment approaches for preterm labor.     

An exploration of the perceived factors that affect the learning and transfer of skills taught to student midwives

Aims and objective

the aim of this study was to examine the attitudes of student midwives towards skills training and practise. The objectives were to explore the factors in the skills laboratory environment and in clinical practice which affect how successfully student midwives transfer into clinical practice the various skills they have learnt in preparation for an Objective Structured Clinical Examination.

Background

a review of the background literature revealed that there were many variables related to successful transfer of skills in general but there appeared to be a gap around perceived factors affecting transfer of skills of student midwives.

Design

a mixed methods design was conducted using both questionnaires and semi-structured interviews between June and August 2010.

Data sources

questionnaires were administered to all midwifery students at one university in Wales. These were later followed by semi-structured interviews for 6 student midwives who were purposively selected from all year groups.

Findings

the results from the questionnaires revealed that a majority of students had positive attitudes to educators and mentors and to their skills acquisition experience in the skills laboratory and to the available opportunities to practise in clinical practice. Although students believed in the transferability of skills from the laboratory setting to clinical practice, a majority thought that clinical practice provided them with a better opportunity to learn clinical skills. The semi-structured interviews demonstrated that facilitating factors in the skills laboratory included having adequate instruction as well as having a designated space. Hindering factors included unrealistic models and equipment. In clinical practice, facilitating factors included having the opportunities to practise skills and support and feedback from the mentor. Hindering factors included deficits in the student–mentor relationship.

Conclusions

this study highlighted that midwifery students must be adequately prepared to carry out clinical skills competently and effectively. Educators and mentors must provide adequate support and feedback to promote transfer of knowledge and skills into the workplace to optimise high standards of care for women and their babies.