Beyond too little, too late and too much, too soon: a pathway towards evidence-based, respectful maternity care worldwide.

Whole-genome shotgun sequencing and sequencing of the gene encoding the 16S rRNA in samples from a variety of body sites in a large cohort of mothers and their infants reveals that, during the 6 weeks after birth, changes in the composition and function of the microbiome are driven by body site but not by the mode of delivery. Human microbial communities are characterized by their taxonomic, metagenomic and metabolic diversity, which varies by distinct body sites and influences human physiology. However, when and how microbial communities within each body niche acquire unique taxonomical and functional signatures in early life remains underexplored. We thus sought to determine the taxonomic composition and potential metabolic function of the neonatal and early infant microbiota across multiple body sites and assess the effect of the mode of delivery and its potential confounders or modifiers. A cohort of pregnant women in their early third trimester (n = 81) were prospectively enrolled for longitudinal sampling through 6 weeks after delivery, and a second matched cross-sectional cohort (n = 81) was additionally recruited for sampling once at the time of delivery. Samples across multiple body sites, including stool, oral gingiva, nares, skin and vagina were collected for each maternal–infant dyad. Whole-genome shotgun sequencing and sequencing analysis of the gene encoding the 16S rRNA were performed to interrogate the composition and function of the neonatal and maternal microbiota. We found that the neonatal microbiota and its associated functional pathways were relatively homogeneous across all body sites at delivery, with the notable exception of the neonatal meconium. However, by 6 weeks after delivery, the infant microbiota structure and function had substantially expanded and diversified, with the body site serving as the primary determinant of the composition of the bacterial community and its functional capacity. Although minor variations in the neonatal (immediately at birth) microbiota community structure were associated with the cesarean mode of delivery in some body sites (oral gingiva, nares and skin; R2 = 0.038), this was not true for neonatal stool (meconium; Mann–Whitney P > 0.05), and there was no observable difference in community function regardless of delivery mode. For infants at 6 weeks of age, the microbiota structure and function had expanded and diversified with demonstrable body site specificity (P < 0.001, R2 = 0.189) but without discernable differences in community structure or function between infants delivered vaginally or by cesarean surgery (P = 0.057, R2 = 0.007). We conclude that within the first 6 weeks of life, the infant microbiota undergoes substantial reorganization, which is primarily driven by body site and not by mode of delivery.

Maturation of the infant microbiome community structure and function across multiple body sites and in relation to mode of delivery.

The International Federation of Gynecology and Obstetrics (FIGO) Initiative on gestational diabetes mellitus: A pragmatic guide for diagnosis, management, and care#

OBJECTIVE
We sought to examine etiology and preventability of maternal death and the causal relationship of cesarean delivery to maternal death in a series of approximately 1.5 million deliveries between 2000 and 2006.


STUDY DESIGN
This was a retrospective medical records extraction of data from all maternal deaths in this time period, augmented when necessary by interviews with involved health care providers. Cause of death, preventability, and causal relationship to mode of delivery were examined.


RESULTS
Ninety-five maternal deaths occurred in 1,461,270 pregnancies (6.5 per 100,000 pregnancies.) Leading causes of death were complications of preeclampsia, pulmonary thromboembolism, amniotic fluid embolism, obstetric hemorrhage, and cardiac disease. Only 1 death was seen from placenta accreta. Twenty-seven deaths (28%) were deemed preventable (17 by actions of health care personnel and 10 by actions of non-health care personnel). The rate of maternal death causally related to mode of delivery was 0.2 per 100,000 for vaginal birth and 2.2 per 100,0000 for cesarean delivery, suggesting that the number of annual deaths resulting causally from cesarean delivery in the United States is about 20.


CONCLUSION
Most maternal deaths are not preventable. Preventable deaths are equally likely to result from actions by nonmedical persons as from provider error. Given the diversity of causes of maternal death, no systematic reduction in maternal death rate in the United States can be expected unless all women undergoing cesarean delivery receive thromboembolism prophylaxis. Such a policy would be expected to eliminate any statistical difference in death rates caused by cesarean and vaginal delivery.

Iconographies supplémentaires de l'article : Maternal death in the 21st century: causes, prevention, and relationship to cesarean delivery

The rate of caesarean section delivery (CSD) is increasing worldwide. It remains unclear whether disruption of mother-to-neonate transmission of microbiota through CSD occurs and whether it affects human physiology. Here we perform metagenomic analysis of earliest gut microbial community structures and functions. We identify differences in encoded functions between microbiomes of vaginally delivered (VD) and CSD neonates. Several functional pathways are over-represented in VD neonates, including lipopolysaccharide (LPS) biosynthesis. We link these enriched functions to individual-specific strains, which are transmitted from mothers to neonates in case of VD. The stimulation of primary human immune cells with LPS isolated from early stool samples of VD neonates results in higher levels of tumour necrosis factor (TNF-α) and interleukin 18 (IL-18). Accordingly, the observed levels of TNF-α and IL-18 in neonatal blood plasma are higher after VD. Taken together, our results support that CSD disrupts mother-to-neonate transmission of specific microbial strains, linked functional repertoires and immune-stimulatory potential during a critical window for neonatal immune system priming. The effects of caesarean section delivery on mother-to-neonate transmission of microbiota are unclear. Here the authors show that caesarean section delivery can affect the transmission of specific microbial strains and the immunomodulatory potential of the microbiota.

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Jeanne Marie Guise

Papers

Safe prevention of the primary cesarean delivery