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Aim: To develop evidence‐based clinical algorithms for the assessment and management of spontaneous, uncomplicated labour and vaginal birth. Population: Pregnant women at any stage of labour, with singleton, term pregnancies considered to be at low risk of developing complications. Setting: Health facilities in low‐ and middle‐income countries. Search Strategy: We searched for relevant published algorithms, guidelines, systematic reviews and primary research studies on Cochrane Library, PubMed, and Google on terms related to spontaneous, uncomplicated labour and childbirth up to 01 June 2023. Case scenarios: Three case scenarios were developed to cover assessments and management for spontaneous, uncomplicated first, second and third stage of labour. The algorithms provide pathways for definition, assessments, diagnosis, and links to other algorithms in this series for management of complications. Conclusions: We have developed three clinical algorithms to support evidence‐based decision making during spontaneous, uncomplicated labour and vaginal birth. These algorithms may help guide health care staff to institute respectful care, appropriate interventions where needed, and potentially reduce the unnecessary use of interventions during labour and childbirth. Evidence‐based clinical algorithms may help support respectful, high quality intrapartum care. [Correction added on 23 August 2024, after first online publication: The Abstract has been updated to structure layout in this version.] [ABSTRACT FROM AUTHOR]

BACKGROUND The establishment of maternal–fetal crosstalk is vital to a successful pregnancy. Glycosylation is a post-translational modification in which glycans (monosaccharide chains) are attached to an organic molecule. Glycans are involved in many physiological and pathological processes. Human endometrial epithelium, endometrial gland secretions, decidual immune cells, and trophoblasts are highly enriched with glycoconjugates and glycan-binding molecules important for a healthy pregnancy. Aberrant glycosylation in the placenta and uterus has been linked to repeated implantation failure and various pregnancy complications, but there is no recent review summarizing the functional roles of glycosylation at the maternal–fetal interface and their associations with pathological processes. OBJECTIVE AND RATIONALE This review aims to summarize recent findings on glycosylation, glycosyltransferases, and glycan-binding receptors at the maternal–fetal interface, and their involvement in regulating the biology and pathological conditions associated with endometrial receptivity, placentation and maternal–fetal immunotolerance. Current knowledge limitations and future insights into the study of glycobiology in reproduction are discussed. SEARCH METHODS A comprehensive PubMed search was conducted using the following keywords: glycosylation, glycosyltransferases, glycan-binding proteins, endometrium, trophoblasts, maternal–fetal immunotolerance, siglec, selectin, galectin, repeated implantation failure, early pregnancy loss, recurrent pregnancy loss, preeclampsia, and fetal growth restriction. Relevant reports published between 1980 and 2023 and studies related to these reports were retrieved and reviewed. Only publications written in English were included. OUTCOMES The application of ultrasensitive mass spectrometry tools and lectin-based glycan profiling has enabled characterization of glycans present at the maternal–fetal interface and in maternal serum. The endometrial luminal epithelium is covered with highly glycosylated mucin that regulates blastocyst adhesion during implantation. In the placenta, fucose and sialic acid residues are abundantly presented on the villous membrane and are essential for proper placentation and establishment of maternal–fetal immunotolerance. Glycan-binding receptors, including selectins, sialic-acid-binding immunoglobulin-like lectins (siglecs) and galectins, also modulate implantation, trophoblast functions and maternal–fetal immunotolerance. Aberrant glycosylation is associated with repeated implantation failure, early pregnancy loss and various pregnancy complications. The current limitation in the field is that most glycobiological research relies on association studies, with few studies revealing the specific functions of glycans. Technological advancements in analytic, synthetic and functional glycobiology have laid the groundwork for further exploration of glycans in reproductive biology under both physiological and pathological conditions. WIDER IMPLICATIONS A deep understanding of the functions of glycan structures would provide insights into the molecular mechanisms underlying their involvement in the physiological and pathological regulation of early pregnancy. Glycans may also potentially serve as novel early predictive markers and therapeutic targets for repeated implantation failure, pregnancy loss, and other pregnancy complications. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the causes of miscarriage and subsequent pregnancy outcomes among different phenotypes of second trimester miscarriage. Methods: Retrospective analysis of 170 consecutive second trimester miscarriages between 14 + 0 and 23 + 6 weeks recorded in the Clinical Data Analysis and Reporting System from 2012 to 2021. Cases were excluded if miscarriages occurred before 14 + 0 weeks of gestation, data were incomplete, or passage of the fetus happened before the clinical assessment. Cases were classified with a stepwise approach into three phenotypic groups including silent miscarriages (ST‐SM), rupture of membranes (ST‐ROM), and inevitable miscarriages (ST‐IM) depending on the fetal heart pulsation and leakage of liquor at presentation. Clinical investigation of the underlying causes and the outcome of the subsequent pregnancy was then reviewed. Results: There were 97 cases of ST‐SM, 21 cases of ST‐ROM, and 52 cases of ST‐IM. Placental histology and karyotype examination were more likely to yield significant results in the cases of ST‐ROM and ST‐SM (p < 0.05). The phenotypic examination identified different underlying causes including fetal anomaly, suspected cervical insufficiency, diabetes mellitus, and unknown causes (p < 0.001). Sixty‐four cases achieved a subsequent pregnancy. Although women with history of ST‐ROM and ST‐IM received more cervical length monitoring and cervical cerclage than those with ST‐SM (66.7% vs. 44.4% vs. 7.5%, p = 0.0002; and 16.7% vs. 22.2% vs. 2.5%, p = 0.031, respectively), the risk of recurrent second trimester miscarriage was higher in ST‐ROM and ST‐IM than in ST‐SM (16.7% vs. 0%, p = 0.018). Conclusion: The classification can differentiate different second trimester miscarriage phenotypes, which offers essential information to guide investigation panels of the underlying cause of miscarriages, and the prognosis and management of subsequent pregnancy. Future researches focused on second trimester miscarriage should report their findings according to different phenotypes. [ABSTRACT FROM AUTHOR]