Connective tissue and related disorders and preterm birth: clues to genes contributing to prematurity

Obstetric outcomes of transabdominal cerclage: A retrospective observational study in Japan

OBJECTIVE

This study aimed to investigate the obstetric outcomes of transabdominal cerclage (TAC) in Japan.

METHODS

Questionnaires on TAC were sent to 183 institutions performing high-quality perinatal management in Japan. As a first-step questionnaire, we asked whether TAC was performed between January 1, 2011, and December 31, 2022. In the second step of the questionnaire, the characteristics of all cases were asked from all institutions in which TAC was performed.

RESULTS

The response rate for the first survey was 59% (108/183). Of the 108 institutions, 27 performed TAC (25%) in 133 pregnancies. Of these 27 institutions, 19 responded to the second survey. One hundred twenty-five pregnancies were included in this study, five of which were aborted (gestational weeks <22 weeks), and 69 babies were born after 37 gestational weeks (55%). Eighty-two open abdominal cerclages were performed at 17 institutions and 43 laparoscopic TACs at three institutions. There were no differences in the age at TAC, gestational weeks at TAC, operative time of TAC, gestational weeks at delivery, incidence rate of second-trimester loss, or preterm delivery (before 37 gestational weeks) rate between the two groups. However, blood loss during open TAC was greater than that during laparoscopic TAC.

CONCLUSION

TAC is a rare surgery for cervical insufficiency in Japan. TAC may be a safe and useful method for preventing second-trimester loss and preterm delivery in high-risk patients. TAC may also be a key option in Japan to improve perinatal outcomes in patients with cervical insufficiency.

A recurrent de novo missense mutation in COL1A1 causes osteogenesis imperfecta type II and preterm delivery in Normande cattle

BACKGROUND

Nine male and eight female calves born to a Normande artificial insemination bull named "Ly" were referred to the French National Observatory of Bovine Abnormalities for multiple fractures, shortened gestation, and stillbirth or perinatal mortality.

RESULTS

Using Illumina BovineSNP50 array genotypes from affected calves and 84 half-sib controls, the associated locus was mapped to a 6.5-Mb interval on chromosome 19, assuming autosomal inheritance with germline mosaicism. Subsequent comparison of the whole-genome sequences of one case and 5116 control genomes, followed by genotyping in the affected pedigree, identified a de novo missense substitution within the NC1 domain of the COL1A1 gene (Chr19 g.36,473,965G > A; p.D1412N) as unique candidate variant. Interestingly, the affected residue was completely conserved among 243 vertebrate orthologs, and the same substitution in humans has been reported to cause type II osteogenesis imperfecta (OI), a connective tissue disorder that is characterized primarily by bone deformity and fragility. Moreover, three COL1A1 mutations have been described to cause the same syndrome in cattle. Necropsy, computed tomography, radiology, and histology confirmed the diagnosis of type II OI, further supporting the causality of this variant. In addition, a detailed analysis of gestation length and perinatal mortality in 1387 offspring of Ly and more than 160,000 progeny of 63 control bulls allowed us to statistically confirm in a large pedigree the association between type II OI and preterm delivery, which is probably due to premature rupture of fetal membranes and has been reported in several isolated cases of type II OI in humans and cattle. Finally, analysis of perinatal mortality rates and segregation distortion supported a low level of germ cell mosaicism in Ly, with an estimate of 4.5% to 7.7% of mutant sperm and thus 63 to 107 affected calves born. These numbers contrast with the 17 cases reported and raise concerns about the underreporting of congenital defects to heredo-surveillance platforms, even for textbook genetic syndromes.

CONCLUSIONS

In conclusion, we describe a large animal model for a recurrent substitution in COL1A1 that is responsible for type II OI in humans. More generally, this study highlights the utility of such datasets and large half-sib families available in livestock species to characterize sporadic genetic defects.

Systems biology approach: identification of hub genes, signaling pathways, and molecular docking of COL1A1 gene in cervical insufficiency

The collagen type I alpha 1 (COL1A1, OMIM #120,150) gene, encoding the alpha-1 chain of type I collagen (UniProt #P02452), plays a key role in life-homeostasis due to its remarkable involvement in collagen synthesis. It is a promising candidate gene implicated in the pathogenesis of cervical insufficiency (CI). This study aimed to identify genetic variations within the COL1A1 gene that contribute to the development of CI. Polymerase chain reaction (PCR) and amplicon sequencing were implemented for single nucleotide polymorphisms (SNPs) detection (+ 1245G/T, SP1 rs1800012), which revealed wild-type sequence for targeted SNPs in enrolled proband indicated negative results regarding COL1A1 gene involvement for current form of CI. It allows further investigation of other closely connected genes probed in this study. Computational approaches viz. Protein-protein interaction (PPI), gene ontology (GO), and pathway participation were used to identify the crucial hub genes and signaling pathways for COL1A1 and CI. Using the Yet Another Scientific Artificial Reality Application (YASARA) software, molecular docking, and molecular dynamic (MD) simulation with the oxytocin (CID 439,302), estradiol (CID 129,728,744), progesterone (CID 5994) and hydroxyprogesterone (CID 150,788) were done. Interactive bioinformatics analysis demonstrated that the COL1A1 and more than 10 collagen sister genes had a strong connection with CI. In sum, the findings of this study provide insights into a modus operandi that can be utilized to illuminate the path toward studying sister genes and smooth diagnosis of CI. These findings have implications for understanding the foundational process of the condition and potentially developing screening, diagnostic, and therapeutic interventions.

Graphical Abstract

No correlation to collagen synthesis disorders in patients with Perthes' disease: a nationwide Swedish register study of 3488 patients

BACKGROUND

Mutations of the COL2A1 gene have been identified in patients with Perthes' disease. Several studies have hypothesised a connection between Perthes' disease and collagen synthesis disorders, especially COL2A1-related disorders, but no large studies on the subject have been made. The aim of this study was thus to discover if there is a connection between patients presenting with Perthes' disease, and collagen synthesis disorders. A secondary aim was to see if the children with both disorders had less optimal birth characteristics than the rest.

METHODS

Swedish national registers were used to collect data on children diagnosed with Perthes' disease or a collagen synthesis disorder. These registers include all births in Sweden, and data from both outpatient and in-hospital visits. A wide range of data is included besides diagnoses. All children with follow-up data to the age of 15 years were included. Pearson's chi-square was used for analysis. Statistical significance was further analysed with Fisher's Exact Test.

RESULTS

In total, 3488 children with either diagnosis were included. 1620 children had only Perthes disease, while 1808 children had only a collagen synthesis disorder. Five children were found to have both the diagnosis Perthes' disease and a collagen synthesis disorder. One child was large for their gestational age and none of the children had a low birthweight. Two of the children were moderately preterm.

CONCLUSIONS

The distinct lack of overlap in such a large body of material raises doubt about a connection between the presentation of Perthes' disease and collagen synthesis disorders, either COL2A1-related or not. We could not find an overrepresentation of less optimal birth characteristics either.

Active versus expectant management for premature rupture of membranes at term: A randomized, controlled study

OBJECTIVE

To compare the effects on feto-maternal outcomes of expectant versus active management for premature rupture of membranes (PROM) at term.

METHODS

This was a prospective randomized (1:1) controlled study involving 86 pregnant-women who received either expectant management (n = 43) or active management with misoprostol (n = 43) for PROM at term. Primary outcome was route of delivery. Secondary outcomes were: PROM to presentation interval; latency period; PROM to delivery interval; recruitment to delivery interval; labour and delivery complications.

RESULTS

Baseline-characteristics were similar between groups. There was no significant difference between active and expectant groups in mean PROM to presentation/admission, or PROM to delivery. However, mean latency period (11.1 ± 7.3 hours vs 8.8 ± 5.5 hours) and mean recruitment to delivery intervals after PROM (14.7 ± 5.2 hours vs 11.8 ± 5.0 hours) were significantly shorter for the active group compared with the expectant group. Although the rate of caesarean section was less in expectant management group (21%) compared with the active management group (30%), the difference was not statistically significant. There were no significant differences between groups in delivery or perinatal complications.

CONCLUSION

Active and expectant management for PROM at term gave comparable outcomes in terms of methods of delivery and complications. However, active management significantly shortened the latency period and induction to delivery intervals compared with expectant management.Trial-Registration: Pan-African-trial-registry-(PACTR)-approval-number PACTR202206797734088.

High Prevalence of Collagenopathies in Preterm- and Term-Born Children With Periventricular Venous Hemorrhagic Infarction

INTRODUCTION

The aim of this study was to evaluate genetic risk factors in term-born children with antenatal periventricular hemorrhagic infarction (PVHI), presumed antenatal periventricular venous infarction and periventricular hemorrhagic infarction in preterm neonates.

METHODS

Genetic analysis and magnetic resonance imaging were performed in 85 children: term-born children (≥36 gestational weeks) with antenatal periventricular hemorrhagic infarction (n = 6) or presumed antenatal (n = 40) periventricular venous infarction and preterm children (<36 gestational weeks) with periventricular hemorrhagic infarction (n = 39). Genetic testing was performed using exome or large gene panel (n = 6700 genes) sequencing.

RESULTS

Pathogenic variants associated with stroke were found in 11 of 85 (12.9%) children with periventricular hemorrhagic infarction/periventricular venous infarction. Among the pathogenic variants, COL4A1/A2 and COL5A1 variants were found in 7 of 11 (63%) children. Additionally, 2 children had pathogenic variants associated with coagulopathy, whereas 2 other children had other variants associated with stroke. Children with collagenopathies had significantly more often bilateral multifocal stroke with severe white matter loss and diffuse hyperintensities in the white matter, moderate to severe hydrocephalus, moderate to severe decrease in size of the ipsilesional basal ganglia and thalamus compared to children with periventricular hemorrhagic infarction/periventricular venous infarction without genetic changes in the studied genes (P ≤ .01). Severe motor deficit and epilepsy developed more often in children with collagenopathies compared to children without genetic variants (P = .0013, odds ratio [OR] = 233, 95% confidence interval [CI]: 2.8-531; and P = .025, OR = 7.3, 95% CI: 1.3-41, respectively).

CONCLUSIONS

Children with periventricular hemorrhagic infarction/periventricular venous infarction have high prevalence of pathogenic variants in collagene genes (COL4A1/A2 and COL5A1). Genetic testing should be considered for all children with periventricular hemorrhagic infarction/periventricular venous infarction; COL4A1/A2 and COL5A1/A2 genes should be investigated first.

Pregnancy and Fetal Outcomes in Patients with Ehlers-Danlos Syndrome: A Nationally Representative Analysis

INTRODUCTION

Cardiovascular (CV) disease remains one of the leading causes of maternal morbidity and mortality globally. CV complications occur frequently in Ehlers-Danlos Syndrome (EDS). Pregnancy outcomes, however, are not well established in patients with EDS. We aim to evaluate pregnancy outcomes in this population compared to patients without EDS.

METHODS

We conducted a population-based, retrospective, cohort study using the national inpatient data sample to evaluate and compare pregnancy and fetal outcomes in patients with and without EDS, delivering between 2016 and 2019. Regression analysis was performed and adjusted for maternal age and race to compare maternal and fetal outcomes.

RESULTS

Of the total 5,887,050 births in our cohort, 1,016 were to patients with EDS. The EDS cohort was more likely to be older and white with multiple gestations and comorbidities, such as smoking, mitral valve prolapse, and chronic hypertension. When we adjusted for age and race, patients with EDS were more likely than those without EDS to require Cesarean-section, develop postpartum hemorrhage, experience intrauterine growth restriction, and deliver preterm.

CONCLUSION

In this nationally representative study, patients with EDS experienced higher rates of maternal complications, however, aortic aneurysmal rupture was not among them. Further studies regarding each type of EDS and its obstetric complications may aid in pre-pregnancy counseling, antenatal care, and formulating a multidisciplinary obstetric approach for this patient population.

SHORT ABSTRACT

Cardiovascular complications occur frequently in Ehlers-Danlos Syndrome (EDS). Pregnancy outcomes, however, are not well established in patients with EDS. We conducted a population-based, retrospective, cohort study using the national inpatient sample to compare pregnancy and fetal outcomes in patients with and without EDS, delivering between 2016 and 2019. Regression analysis was performed and adjusted for maternal age and race to compare both groups. Of the total 5,887,050 births in our cohort, 1,016 were to patients with EDS. The EDS cohort was more likely to be older, white and have multiple comorbidities, such as smoking, mitral valve prolapse, and chronic hypertension. When we adjusted for age and race, patients with EDS were more likely than those without EDS to require Cesarean-section, develop postpartum hemorrhage, experience intrauterine growth restriction, and deliver preterm. In this study, patients with EDS experienced higher rates of maternal complications, however, aortic aneurysmal rupture was not among them.

Progesterone and its receptor signaling in cervical remodeling: Mechanisms of physiological actions and therapeutic implications

The remodeling of the cervix from a closed rigid structure to one that can open sufficiently for passage of a term infant is achieved by a complex series of molecular events that in large part are regulated by the steroid hormones progesterone and estrogen. Among hormonal influences, progesterone exerts a dominant role for most of pregnancy to initiate a loss of tissue strength yet maintain competence in a phase termed softening. Equally important are the molecular events that abrogate progesterone function in late pregnancy to allow a loss of tissue competence and strength during cervical ripening and dilation. In this review, we focus on current understanding by which progesterone receptor signaling for the majority of pregnancy followed by a loss/shift in progesterone receptor action at the end of pregnancy, collectively ensure cervical remodeling as necessary for successful parturition.

Mechanical Response of Mouse Cervices Lacking Decorin and Biglycan During Pregnancy

Cervical remodeling is critical for a healthy pregnancy. The proper regulation of extracellular matrix (ECM) turnover leads to remodeling throughout gestation, transforming the tissue from a stiff material to a compliant, extensible, viscoelastic tissue prepared for delivery. Small leucine rich proteoglycans (SLRPs) are known to regulate structural fiber assembly in the cervical ECM and overall tissue material properties. To quantify the SLRPs' mechanical role in the cervix, whole cervix specimens from non-pregnant and late pregnant knockout mice of SLRPs, decorin and biglycan, were subjected to cyclic load-unload, ramp-hold, and load-to-failure mechanical tests. Further, a fiber composite material model, accounting for collagen fiber bundle waviness, was developed to describe the three-dimensional large deformation equilibrium behavior of the cervix. In nonpregnant tissue, SLRP KO cervices have the same equilibrium material properties as wild-type tissue. In contrast, the load-to-failure and ramp-hold tests reveal SLRPs impact rupture and time-dependent relaxation behavior. Loss of decorin in NP cervices results in inferior rupture properties. While remodeling recovers cervical strength, the SLRP-deficient tissue has diminished ability to dissipate stress during a ramp-hold. In mice with a combined loss of decorin and biglycan, the pregnant cervix loses its extensibility, compliance, and viscoelasticity. Taken together, these results suggest decorin and biglycan are necessary for key compliance and viscoelastic material property features of a healthy remodeled pregnant cervix.

Study protocol to quantify the genetic architecture of sonographic cervical length and its relationship to spontaneous preterm birth

INTRODUCTION

A short cervix (cervical length <25 mm) in the midtrimester (18-24 weeks) of pregnancy is a powerful predictor of spontaneous preterm delivery. Although the biological mechanisms of cervical change during pregnancy have been the subject of extensive investigation, little is known about whether genes influence the length of the cervix, or the extent to which genetic factors contribute to premature cervical shortening. Defining the genetic architecture of cervical length is foundational to understanding the aetiology of a short cervix and its contribution to an increased risk of spontaneous preterm delivery.

METHODS/ANALYSIS

The proposed study is designed to characterise the genetic architecture of cervical length and its genetic relationship to gestational age at delivery in a large cohort of Black/African American women, who are at an increased risk of developing a short cervix and delivering preterm. Repeated measurements of cervical length will be modelled as a longitudinal growth curve, with parameters estimating the initial length of the cervix at the beginning of pregnancy, and its rate of change over time. Genome-wide complex trait analysis methods will be used to estimate the heritability of cervical length growth parameters and their bivariate genetic correlation with gestational age at delivery. Polygenic risk profiling will assess maternal genetic risk for developing a short cervix and subsequently delivering preterm and evaluate the role of cervical length in mediating the relationship between maternal genetic variation and gestational age at delivery.

ETHICS/DISSEMINATION

The proposed analyses will be conducted using deidentified data from participants in an IRB-approved study of longitudinal cervical length who provided blood samples and written informed consent for their use in future genetic research. These analyses are preregistered with the Center for Open Science using the AsPredicted format and the results and genomic summary statistics will be published in a peer-reviewed journal.

CD73+ adipose-derived stem cells reduce scar formation through PLOD1

Background

Reducing cutaneous scar formation is important for assessing the success of skin wound healing. Although it is generally accepted that adipose-derived mesenchymal stem cells (AMSCs) have substantial therapeutic potential, efforts are continuously made to improve the outcome of AMSC therapy. Post-transcriptional suppression of procollagen-lysine 1, 2-oxoglutarate 5-dioxygenase 1 (PLOD1) in AMSCs has been shown to greatly reduce scar formation during skin wound healing, likely through modulating macrophage polarization. In the present study, we tested whether a CD73⁺ subpopulation of AMSCs could reduce scar formation compared with CD73^– AMSCs.

Methods

The gene profile of CD73⁺ versus CD73^– AMSCs was obtained from a validated public database, GSE167219. AMSCs were isolated from adipose tissue surrounding the groin of mice, after which CD73⁺ versus CD73^– AMSCs were sorted using flow cytometry. PLOD1 levels were determined in CD73⁺ versus CD73^– AMSCs. Then, PLOD1 in CD73^– AMSCs was depleted by a short-hair interfering RNA against PLOD1 (sh-PLOD1), while PLOD1 in CD73⁺ AMSCs was increased by expression of a PLOD1 transgene. A blade was used to induce a skin injury on the middle back of the mice. Either CD73⁺ AMSCs or CD73⁺ PLOD1 AMSCs or CD73^– AMSCs or CD73^– sh-PLOD1 AMSCs were intravenously transplanted into the injured region of the mice. Fibrosis and the underlying mechanisms were investigated. Co-immunoprecipitation was performed to evaluate interaction between CD73 and PLOD1.

Results

CD73⁺ AMSCs expressed significantly lower levels of PLOD1, a potent stimulator of fibrosis, compared with CD73^– AMSCs. Transplantation of CD73⁺ AMSCs generated significantly reduced fibrosis at the skin injury site compared with CD73^– AMSCs. However, expression of PLOD1 in CD73⁺ AMSCs abolished its advantageous effects on fibrosis reduction, while depletion of PLOD1 in CD73^– AMSCs improved the outcome of fibrosis to the levels of transplantation of CD73⁺ AMSCs. Co-immunoprecipitation showed no direct protein interaction between CD73 and PLOD1.

Conclusions

CD73⁺ AMSCs are a subgroup of AMSCs with better therapeutic effects on wound healing, and can inhibit scar formation through reduced PLOD1 in an indirect manner.

Posttranscriptional control of PLOD1 in adipose-derived stem cells regulates scar formation through altering macrophage polarization

Background

The level of cutaneous scar formation is a critical parameter to determine the success of skin wound healing. Adipose-derived mesenchymal stem cells (AMSCs) have been applied to improve treatment of cutaneous injury with the purpose of reducing scar formation.

Methods

The levels of procollagen-lysine 1,2-oxoglutarate 5-dioxygenase 1 (PLOD1) were assessed at scar sites. Then, PLOD1 in AMSCs was depleted by either expression of a PLOD1-specific short-hair interfering RNA (shPLOD1) or by expression of microRNA-449 (miR-449) that targets and suppresses protein translation of PLOD1 through 3 prime untranslated region (3'-UTR) interfering. For induction of skin injury, a blade cut of 1.5-cm long and 2-mm thick was made on the middle back of the mice. Transplantation of either AMSCs-shPLOD1 or AMSCs-miR-449 into the injured region of the mice was performed via tail vein injection. The fibrosis as well as underlying mechanisms were assessed.

Results

The AMSCs expressed high levels of PLOD1, a potent stimulator of fibrosis. We knocked down PLOD1 in AMSCs by expression of either shPLOD1 or miR-449. Transplantation of either AMSCs-shPLOD1 or AMSCs-miR-449 significantly reduced the fibrotic process in the injured region of the mice to a similar degree. Mechanistically, transplantation of either AMSCs-shPLOD1 or AMSCs-miR-449 shifted macrophage polarization from M2 to M1-like and reduced both reactive oxygen species (ROS) and activation of myofibroblasts from fibroblasts.

Conclusions

Suppression of PLOD1 levels in AMSCs either directly by shPLOD1 or indirectly by miR-449 may substantially improve the anti-fibrotic potential of AMSCs during wound healing, likely through altering macrophage polarization.

Health repercussions of environmental exposure to lead: Methylation perspective

Lead (Pb) exposure has been a major public health concern for a long time now due to its permanent adverse effects on the human body. The process of lead toxicity has still not been fully understood, but recent advances in Omics technology have enabled researchers to evaluate lead-mediated alterations at the epigenome-wide level. DNA methylation is one of the widely studied and well-understood epigenetic modifications. Pb has demonstrated its ability to induce not just acute deleterious health consequences but also alters the epi-genome such that the disease manifestation happens much later in life as supported by Barkers Hypothesis of the developmental origin of health and diseases. Furthermore, these alterations are passed on to the next generation. Based on previous in-vivo, in-vitro, and human studies, this review provides an insight into the role of Pb in the development of several human disorders.

A comparative analysis of the intrauterine transcriptome in fertile and subfertile mares using cytobrush sampling

Background

Subfertility is a major problem in modern horse breeding. Especially, mares without clinical signs of reproductive diseases, without known uterine pathogens and no evidence of inflammation but not becoming pregnant after several breeding attempts are challenging for veterinarians. To obtain new insights into the cause of these fertility problems and aiming at improving diagnosis of subfertile mares, a comparative analysis of the intrauterine transcriptome in subfertile and fertile mares was performed. Uterine cytobrush samples were collected during estrus from 57 mares without clinical signs of uterine diseases. RNA was extracted from the cytobrush samples and samples from 11 selected subfertile and 11 fertile mares were used for Illumina RNA-sequencing.

Results

The cytobrush sampling was a suitable technique to isolate enough RNA of high quality for transcriptome analysis. Comparing subfertile and fertile mares, 114 differentially expressed genes (FDR = 10%) were identified. Metascape enrichment analysis revealed that genes with lower mRNA levels in subfertile mares were related to ‘extracellular matrix (ECM)’, ‘ECM-receptor interaction’, ‘focal adhesion’, ‘immune response’ and ‘cytosolic calcium ion concentration’, while DEGs with higher levels in subfertile mares were enriched for ‘monocarboxyl acid transmembrane transport activity’ and ‘protein targeting’.

Conclusion

Our study revealed significant differences in the uterine transcriptome between fertile and subfertile mares and provides leads for potential uterine molecular biomarkers of subfertility in the mare.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07701-3.

Ehlers-Danlos Syndrome in Pregnancy: A Review

Ehlers-Danlos syndrome (EDS) is a group of connective tissue disorders that can result in a range of complications during pregnancy. Pregnant EDS patients generally have a favourable outcome, but those with vascular EDS are more likely to suffer from severe maternal complications. Early diagnosis of EDS and subtype characterization can aid in pre-pregnancy counselling, planning of antenatal care, risk assessment of obstetric and neonatal complications, and influence both obstetric and anaesthetic management of these patients. This piece aims to outline the obstetric implications of classical, hypermobile, and vascular EDS, and review the current literature regarding their optimal obstetric management.

Cervical insufficiency: a noteworthy disease with controversies

Cervical insufficiency (CI) is a mainly disease leading to recurrent abortions and preterm birth which may present in about 1% of obstetric populations. Recurrent pregnancy losses caused by CI incur serious economic burdens on society as well as huge psychological burdens to family members. However, many patients even clinicians in some areas of the world still remain confused about this disease. At the same time, the etiology of CI is still uncertain and it is still a controversial disease in diagnosis and treatment. This article summarizes the potential risk factors associated with CI, which could be worthy of attention and helpful for future research. It also reviews the methods for diagnosis and treatment of CI to better understand this noteworthy disease, as well as presents the related consensus and controversies according to the newly updated guidelines, which has practical significance for conducting more in-depth investigations in the future.

Pregnancy outcomes in women with Ehlers-Danlos Syndrome

PURPOSE

Ehlers-Danlos Syndrome (EDS) is an inherited connective tissue disorder caused by abnormal collagen synthesis. Little is known about its effects on pregnancy. The purpose of this study was to evaluate the pregnancy outcomes in women with EDS.

MATERIALS AND METHODS

We conducted a population-based retrospective cohort study using the Healthcare Cost and Utilization Project Nationwide Inpatient Sample database from the United States. The study included women who delivered between 1999 and 2014. We measured the prevalence of EDS over time, and compared the baseline, obstetrical, and neonatal outcomes among women with EDS to the general obstetrical population without EDS. Unconditional logistic regression models were used to calculate the adjusted effect of EDS on maternal and neonatal outcomes.

RESULTS

The overall prevalence of EDS in pregnancy was 7 per 100,000 births, with the trend increasing over the 16 year study period (p < .0001). Women with EDS were more likely to be Caucasian, belong to a higher income quartile, and smoke. Pregnancies in women with EDS were associated with prematurity, 1.47 (1.18-1.82), cervical incompetence, 3.11 (1.99-4.85), antepartum hemorrhage, 1.71 (1.16-2.50), placenta previa, 2.26 (1.35-3.77) and maternal death, 9.04 (1.27-64.27). Pregnant women with EDS were more likely to be delivered by cesarean section, 1.55 (1.36-1.76), have longer postpartum stays (>7 days), 2.82 (2.08-3.85), and have a neonate with intra-uterine growth restriction, 1.81 (1.29-2.54).

CONCLUSIONS

EDS in pregnancy is a high-risk condition with increased maternal morbidity and mortality, as well as newborn morbidity. Consideration should be given to prematurity preventative measures and high-risk pregnancy consultation.

The Role of Danger Associated Molecular Patterns in Human Fetal Membrane Weakening

The idea that cellular stress (including that precipitated by stretch), plays a significant role in the mechanisms initiating parturition, has gained considerable traction over the last decade. One key consequence of this cellular stress is the increased production of Danger Associated Molecular Patterns (DAMPs). This diverse family of molecules are known to initiate inflammation through their interaction with Pattern Recognition Receptors (PRRs) including, Toll-like receptors (TLRs). TLRs are the key innate immune system surveillance receptors that detect Pathogen Associated Molecular Patterns (PAMPs) during bacterial and viral infection. This is also seen during Chorioamnionitis. The activation of TLR commonly results in the activation of the pro-inflammatory transcription factor Nuclear Factor Kappa-B (NF-kB) and the downstream production of pro-inflammatory cytokines. It is thought that in the human fetal membranes both DAMPs and PAMPs are able, perhaps via their interaction with PRRs and the induction of their downstream inflammatory cascades, to lead to both tissue remodeling and weakening. Due to the high incidence of infection-driven Pre-Term Birth (PTB), including those that have preterm Premature Rupture of the Membranes (pPROM), the role of TLR in fetal membranes with Chorioamnionitis has been the subject of considerable study. Most of the work in this field has focused on the effect of PAMPs on whole pieces of fetal membrane and the resultant inflammatory cascade. This is important to understand, in order to develop novel prevention, detection, and therapeutic approaches, which aim to reduce the high number of mothers suffering from infection driven PTB, including those with pPROM. Studying the role of sterile inflammation driven by these endogenous ligands (DAMPs) activating PRRs system in the mesenchymal and epithelial cells in the amnion is important. These cells are key for the maintenance of the integrity and strength of the human fetal membranes. This review aims to (1) summarize the knowledge to date pertinent to the role of DAMPs and PRRs in fetal membrane weakening and (2) discuss the clinical potential brought by a better understanding of these pathways by pathway manipulation strategies.

Preterm Birth of Infants Prenatally Diagnosed with Congenital Heart Disease, Characteristics, Associations, and Outcomes

There are limited data on the relation between congenital heart disease (CHD) and preterm birth (PTB). We aimed to estimate the risk of PTB in newborns with CHD, to study associations and risk factors (modifiable and non-modifiable) as well as investigate postnatal outcomes. This was a retrospective cohort study of 336 pregnancies diagnosed with CHD between 2011 and 2016. Groups consisted of those delivered at or after 37 weeks, and those who delivered prior to 37 weeks. Collected data included maternal and fetal characteristics as well postnatal outcomes. Complete data were obtained from 237 singleton pregnancies. The overall proportion of PTB was 23.2% for all CHD, of which 38.2% were spontaneous PTB which was almost unchanged after excluding extracardiac anomalies and pathogenic chromosomal abnormalities. Significant non-modifiable risk factors were pregnancy-related HTN disorders (P < 0.001), fetal growth restriction (P = 0.01), and pathogenic chromosomal abnormalities (P = 0.046). Significant PTB modifiable risk factors included prenatal marijuana use (P = 0.01). Pregnancies delivered at 37-38 weeks had significantly more newborns with birthweight < 2500 g (P < 0.001), required more pre-operative NICU support including intubation (P = 0.049), vasopressors (P = 0.04), prostaglandins (P = 0.003), antibiotics (P = 0.01), and had longer hospital stay (P = 0.001) than those delivered at ≥ 39 weeks. Prenatally diagnosed pregnancies with CHD had higher PTB rate compared to the general population, with spontaneous PTB comprising 38.2% of these preterm deliveries. Most PTB risk factors were non-modifiable, however, significant modifiable factors included marijuana use in pregnancy. Outcomes were favorable in neonates delivered at or beyond 39 weeks.

Pregnancy management in a patient with stickler syndrome

BACKGROUND

Stickler syndrome is a collagen disorder that can affect multiple organ systems. It is characterized by ocular abnormalities, hearing loss, midfacial hypoplasia, hypermobility, and joint abnormalities. The phenotypic expression of Stickler syndrome can vary among those affected. Since Stickler syndrome is a collagen disorder, it is possible to expect pregnancy complications similar to those reported in other collagen disorders. To our knowledge, there is only one case report in the literature on the management of pregnancy and delivery of a patient with Stickler syndrome.

METHODS/CASE REPORT

A 37-year-old primigravid woman with a diagnosis of Stickler syndrome presented at 9 weeks gestation for prenatal genetic consultation. At 26, the patient had prophylactic laser therapy for lattice degeneration of the retina. At 32, she was found to be heterozygous for the c.1527 G>T variant in the COL2A1 gene, which is associated with ocular abnormalities and autosomal dominant form of Stickler syndrome. Subsequently, she desired to pursue prenatal diagnostic testing for the familial variant. The patient voiced that the results would impact pregnancy management. Amniocentesis was performed at 16 weeks gestation. Results were negative for the maternal COL2A1 variant. Karyotype was normal (46, XX).

RESULTS

A multidisciplinary team using a patient-centered approach including obstetrics, ophthalmology, maternal-fetal medicine, and genetics determined that there were no contraindications for vaginal delivery. At 39 weeks, the patient underwent spontaneous vaginal delivery with no complications.

CONCLUSION

There is a paucity of data available regarding the maternal outcomes of women affected with collagen disorders, especially Stickler Syndrome. This case highlights the importance of accurate genetic diagnosis in the prenatal period and provides information to physicians caring for patients with Stickler syndrome.

Tenascin-X in amniotic fluid and reproductive tissues of pregnancies complicated by infection and preterm prelabor rupture of membranes†

Preterm prelabor rupture of membranes (PPROM), which can precede or follow intra-amniotic infection/inflammation (IAI), is a poorly understood pregnancy complication. Tenascin-X (TNX) is a connective tissue extracellular matrix protein that regulates fibrillogenesis of collagens I, III, and V. Our goal was to investigate the presence and level of soluble TNX (sTNX) in amniotic fluid (AF) and TNX expression in reproductive tissues of pregnancies complicated by PPROM and IAI. We prospectively recruited 334 women pregnant with singletons who had a clinically indicated amniocentesis for genetic karyotyping, lung maturity testing, or rule-out IAI in the presence or absence of PPROM. We quantified TNX expression in fetal membranes, myometrium, cervix, and placenta using immunological methods and qRT-PCR. In pregnancies with normal outcomes, AF sTNX levels were GA-regulated with lower levels toward term. IAI significantly upregulated AF sTNX levels independent of membrane status. AF sTNX levels inversely correlated with fetal membranes tenascin XB (TNXB) mRNA level, which was significantly downregulated by IAI. Western blotting identified characteristic ∼75 and ∼140 kDa sTNX forms in both AF and fetal membranes. Fetal membranes, placenta, and cervix constitutively express TNX with the highest abundance in the amnion. Amnion TNX richness is significantly lost in the setting of IAI. Our results suggest that fetal membranes may be a source of AF sTNX whereby protein and mRNA expression seem to be significantly impacted by inflammation independent of fetal membrane status. A more thorough understanding of TNX changes may be valuable for understanding spontaneous PPROM and to potentially develop therapeutic targets.

Genetical modification on adipose-derived stem cells facilitates facial nerve regeneration

Adipose-derived stem cells (ASCs) have a demonstrative therapeutic potential in aging-associated facial nerve regeneration, in which ASCs work as a source of Schwann cells therapy as an alternative to autologous nerve grafts. However, the transplantation of ASCs may induce local fibrosis, which causes inferior outcome. Here, we aimed to use genetic modification approaches to reduce the fibrogenic properties of ASCs to improve their therapeutic effects on facial nerve regeneration. Since procollagen-lysine 1, 2-oxoglutarate 5-dioxygenase 1 (PLOD1) is essential for hydroxylation of lysine residues in collagen telopeptides and for collagen pyridinoline cross-link formation during fibrosis, and since we found that ASCs expressed high levels of PLOD1, we depleted PLOD1 in ASCs by expression of either a short-hair interfering RNA for PLOD1 (shPLOD1) or a microRNA-449 (miR-449), the latter of which targets PLOD1 mRNA to suppress protein translation. Transplantation of either ASCs-shPLOD1 or ASCs-miR-449 or ASCs-control to repair a 6mm-gap in rat facial nerve was compared. Either ASCs-shPLOD1 or ASCs-miR-449 exhibited a better facial nerve function. Mechanistically, ASCs-shPLOD1 or ASCs-miR-449 significantly and similarly reduced the fibrosis in the injured region, likely through suppression of reactive oxygen species (ROS) and activation of myofibroblasts.

Genetic landscape of preterm birth due to cervical insufficiency: Comprehensive gene analysis and patient next-generation sequencing data interpretation

Preterm delivery is both a traumatizing experience for the patient and a burden on the healthcare system. A condition distinguishable by its phenotype in prematurity is cervical insufficiency, where certain cases exhibit a strong genetic component. Despite genomic advancements, little is known about the genetics of human cervix remodeling during pregnancy. Using selected gene approaches, a few studies have demonstrated an association of common gene variants with cervical insufficiency. However, until now, no study has employed comprehensive methods to investigate this important subject matter. In this study, we asked: i) are there genes reliably linked to cervical insufficiency and, if so, what are their roles? and ii) what is the proportion of cases of non-syndromic cervical insufficiency attributable to these genetic variations? We performed next-generation sequencing on 21 patients with a clinical presentation of cervical insufficiency. To assist the sequencing data interpretation, we retrieved all known genes implicated in cervical functioning through a systematic literature analysis and additional gene searches. These genes were then classified according to their relation to the questions being posed by the study. Patients' sequence variants were filtered for pathogenicity and assigned a likelihood of being contributive to phenotype development. Gene extraction and analysis revealed 12 genes primarily linked to cervical insufficiency, the majority of which are known to cause collagenopathies. Ten patients carried disruptive variants potentially contributive to the development of non-syndromic cervical insufficiency. Pathway enrichment analysis of variant genes from our cohort revealed an increased variation burden in genes playing roles in tissue mechanical and biomechanical properties, i.e. collagen biosynthesis and cell-extracellular matrix communications. Consequently, the proposed idea of cervical insufficiency being a subtle form of collagenopathy, now strengthened by our genetic findings, might open up new opportunities for improved patient evaluation and management.

Amniotic band sequence in paternal half-siblings with vascular Ehlers-Danlos syndrome

Familial amniotic band sequence (ABS) is rare but has been reported in the offspring of mothers with connective tissue disorders. We present a family of two half-siblings with ABS who share the same biological father. Following a serious vascular event a de novo pathogenic variant in COL3A1 was detected in the father, confirming a diagnosis of vascular Ehlers-Danlos syndrome (vEDS). The same variant was found in both his ABS-affected children but not in his unaffected child. The amniotic membrane is derived from fetal tissue, type III collagen being a component. As the affected children are paternal half-siblings, ABS was less likely due to maternal factors. Rather, the amniotic bands may have resulted from decreased type III collagen production as seen in people with vEDS, causing fragility of the amniotic membrane. Consequently, it is important to consider vEDS in patients with ABS.

Epigenetic changes in preterm birth placenta suggest a role for ADAMTS genes in spontaneous preterm birth

Preterm birth (PTB) affects approximately 1 in 10 pregnancies and contributes to approximately 50% of neonatal mortality. However, despite decades of research, little is understood about the etiology of PTB, likely due to the multifactorial nature of the disease. In this study, we examined preterm and term placentas, from unassisted conceptions and those conceived using in vitro fertilization (IVF). IVF increases the risk of PTB and causes epigenetic change in the placenta and fetus; therefore, we utilized these patients as a unique population with a potential common etiology. We investigated genome-wide DNA methylation in placentas from term IVF, preterm IVF, term control (unassisted conception) and preterm control pregnancies and discovered epigenetic dysregulation of multiple genes involved in cell migration, including members of the ADAMTS family, ADAMTS12 and ADAMTS16. These genes function in extracellular matrix regulation and tumor cell invasion, processes replicated by invasive trophoblasts (extravillous trophoblasts (EVTs)) during early placentation. Though expression was similar between term and preterm placentas, we found that both genes demonstrate high expression in first- and second-trimester placenta, specifically in EVTs and syncytiotrophoblasts. When we knocked down ADAMTS12 or ADAMTS16in vitro, there was poor EVT invasion and reduced matrix metalloproteinase activity, reinforcing their critical role in placentation. In conclusion, utilizing a population at high risk for PTB, we have identified a role for ADAMTS gene methylation in regulating early placentation and susceptibility to PTB.

Understanding fetal factors that contribute to preterm birth: Sjögren-Larsson syndrome as a model

AIM

Preterm birth is the world's leading cause of neonatal death. Unfortunately, the pathophysiology of preterm birth remains poorly understood. Sjögren-Larsson syndrome is a rare, neurometabolic disorder caused by a fatty aldehyde dehydrogenase deficiency. A majority of patients with Sjögren-Larsson syndrome is born preterm.

METHODS

Data of all known Dutch patients with Sjögren-Larsson syndrome and all cases reported in literature were analyzed to learn from preterm birth in context of this rare disease.

RESULTS

Exact gestational age was known in 33 Dutch patients; 24 (73%) of them were born preterm, with a median gestational age of 36 weeks. The literature search confirmed our findings: 13 (59%) of 22 cases was born preterm.

CONCLUSIONS

Preterm birth is a hallmark of Sjögren-Larsson syndrome, presumably caused by the abnormal lipid metabolism of the fetus. At least five additional rare genetic disorders (namely Ehlers-Danlos syndrome, ichthyosis prematurity syndrome, congenital analbuminemia, osteogenesis imperfecta type II and restrictive dermopathy) were found in literature that lead to preterm birth of the affected fetus. These disorders are in fact "experiments of nature" and as such they shed new lights on the mechanisms causing preterm birth.

Mutations in fetal genes involved in innate immunity and host defense against microbes increase risk of preterm premature rupture of membranes (PPROM)

BACKGROUND

Twin studies have revealed a significant contribution of the fetal genome to risk of preterm birth. Preterm premature rupture of membranes (PPROM) is the leading identifiable cause of preterm delivery. Infection and inflammation of the fetal membranes is commonly found associated with PPROM.

METHODS

We carried out whole exome sequencing (WES) of genomic DNA from neonates born of African-American mothers whose pregnancies were complicated by PPROM (76) or were normal term pregnancies (N = 43) to identify mutations in 35 candidate genes involved in innate immunity and host defenses against microbes. Targeted genotyping of mutations in the candidates discovered by WES was conducted on an additional 188 PPROM cases and 175 controls.

RESULTS

We identified rare heterozygous nonsense and frameshift mutations in several of the candidate genes, including CARD6, CARD8, DEFB1, FUT2, MBL2, NLP10, NLRP12, and NOD2. We discovered that some mutations (CARD6, DEFB1, FUT2, MBL2, NLRP10, NOD2) were present only in PPROM cases.

CONCLUSIONS

We conclude that rare damaging mutations in innate immunity and host defense genes, the majority being heterozygous, are more frequent in neonates born of pregnancies complicated by PPROM. These findings suggest that the risk of preterm birth in African-Americans may be conferred by mutations in multiple genes encoding proteins involved in dampening the innate immune response or protecting the host against microbial infection and microbial products.

Fetal de novo mutations and preterm birth

Preterm birth (PTB) affects ~12% of pregnancies in the US. Despite its high mortality and morbidity, the molecular etiology underlying PTB has been unclear. Numerous studies have been devoted to identifying genetic factors in maternal and fetal genomes, but so far few genomic loci have been associated with PTB. By analyzing whole-genome sequencing data from 816 trio families, for the first time, we observed the role of fetal de novo mutations in PTB. We observed a significant increase in de novo mutation burden in PTB fetal genomes. Our genomic analyses further revealed that affected genes by PTB de novo mutations were dosage sensitive, intolerant to genomic deletions, and their mouse orthologs were likely developmentally essential. These genes were significantly involved in early fetal brain development, which was further supported by our analysis of copy number variants identified from an independent PTB cohort. Our study indicates a new mechanism in PTB occurrence independently contributed from fetal genomes, and thus opens a new avenue for future PTB research.

Preterm birth is a prevalent pregnancy condition and leads to substantial morbidity and mortality. Its genetic association has been well observed, but the underlying etiology remains unclear. Current research has been focused on identifying risk factors in maternal genomes. In this study, we tested an unexplored hypothesis that preterm birth could be independently influenced by fetal genomes. We analyzed fetal de novo mutations, those not inherited from parents, from 816 trio families, and found preterm infants tended to have increased de novo mutation rates compared to infants born at term. Importantly, we also observed that these preterm-associated de novo mutations preferentially affect dosage sensitive genes that are essential in embryonic development, and these affected genes are involved in early fetal brain development. Overall, our study for the first time showed the fetal genetic contribution to preterm birth, and suggested abnormal fetal development as a potential cause for preterm birth.

Steroid Hormones Are Key Modulators of Tissue Mechanical Function via Regulation of Collagen and Elastic Fibers

The extracellular matrix (ECM) plays an active and dynamic role that both reflects and facilitates the functional requirements of a tissue. The mature ECM of the nonpregnant cervix is drastically reorganized during pregnancy to drive changes in tissue mechanics that ensure safe birth. In this study, our research on mice deficient in the proteoglycan decorin have led to the finding that progesterone and estrogen play distinct and complementary roles to orchestrate structural reorganization of both collagen and elastic fibers in the cervix during pregnancy. Abnormalities in collagen and elastic fiber structure and tissue mechanical function evident in the cervix of nonpregnant and early pregnant decorin-null mice transiently recover for the remainder of pregnancy only to return 1 month postpartum. Consistent with the hypothesis that pregnancy levels of progesterone and estrogen may regulate ECM organization and turnover, expressions of factors required for assembly and synthesis of collagen and elastic fibers are temporally regulated, and the ultrastructure of collagen fibrils and elastic fibers is markedly altered during pregnancy in wild-type mice. Finally, utilizing ovariectomized nonpregnant decorin-null mice, we demonstrate structural resolution of collagen and elastic fibers by progesterone or estrogen, respectively, and the potential for both ECM proteins to contribute to mechanical function. These investigations advance understanding of regulatory factors that drive specialized ECM organization and contribute to an understanding of the cervical remodeling process, which may provide insight into potential complications associated with preterm birth that impact 9.6% of live births in the United States.

Rare mutations and potentially damaging missense variants in genes encoding fibrillar collagens and proteins involved in their production are candidates for risk for preterm premature rupture of membranes

Preterm premature rupture of membranes (PPROM) is the leading identifiable cause of preterm birth with ~ 40% of preterm births being associated with PPROM and occurs in 1% - 2% of all pregnancies. We hypothesized that multiple rare variants in fetal genes involved in extracellular matrix synthesis would associate with PPROM, based on the assumption that impaired elaboration of matrix proteins would reduce fetal membrane tensile strength, predisposing to unscheduled rupture. We performed whole exome sequencing (WES) on neonatal DNA derived from pregnancies complicated by PPROM (49 cases) and healthy term deliveries (20 controls) to identify candidate mutations/variants. Genotyping for selected variants from the WES study was carried out on an additional 188 PPROM cases and 175 controls. All mothers were self-reported African Americans, and a panel of ancestry informative markers was used to control for genetic ancestry in all genetic association tests. In support of the primary hypothesis, a statistically significant genetic burden (all samples combined, SKAT-O p-value = 0.0225) of damaging/potentially damaging rare variants was identified in the genes of interest-fibrillar collagen genes, which contribute to fetal membrane strength and integrity. These findings suggest that the fetal contribution to PPROM is polygenic, and driven by an increased burden of rare variants that may also contribute to the disparities in rates of preterm birth among African Americans.

Recurrence rates after abdominal and vaginal cerclages in women with cervical insufficiency: a validated cohort study

PURPOSE

To estimate the incidence of cervical insufficiency and compare recurrence rates of second trimester miscarriage/delivery in second and third pregnancies after prophylactic vaginal cerclage, abdominal cerclage, or no cerclage.

METHODS

Retrospective chart review of a representative register-based sample of 621 women with a spontaneous second trimester miscarriage/delivery in the first pregnancy in Denmark (1997-2012). We used strict criteria for the diagnosis of cervical insufficiency. The outcome of subsequent pregnancies was described by treatment with prophylactic vaginal cerclage, abdominal cerclage, or no prophylactic cerclage. Women were followed until June 2015.

RESULTS

Of 621 women, 149 (24%) fulfilled the strict criteria of cervical insufficiency. Prophylactic treatment with abdominal cerclage (n = 20), vaginal cerclage (n = 59), and no prophylactic cerclage (n = 61) resulted in a second pregnancy ending before 28 weeks in 5, 30, and 72% (p < 0.001) and before 34 weeks in 10, 46, and 84% (p < 0.001), respectively. Take-home baby rate was 95% after abdominal cerclage, 73% after vaginal cerclage, and 33% after no cerclage. In a third pregnancy, abdominal cerclage (n = 47), vaginal cerclage (n = 38), and no cerclage (n = 8) resulted in pregnancy ending before 34 weeks of gestation in 2, 21, and 25%, respectively (p = 0.01).

CONCLUSIONS

Cervical insufficiency was diagnosed in 24% of women with an initial second trimester spontaneous miscarriage/delivery. In second and third pregnancies, recurrence rates were significantly lower after prophylactic vaginal or abdominal cerclage compared with no cerclage.

Cliff-edge model of obstetric selection in humans

The strikingly high incidence of obstructed labor due to the disproportion of fetal size and the mother's pelvic dimensions has puzzled evolutionary scientists for decades. Here we propose that these high rates are a direct consequence of the distinct characteristics of human obstetric selection. Neonatal size relative to the birth-relevant maternal dimensions is highly variable and positively associated with reproductive success until it reaches a critical value, beyond which natural delivery becomes impossible. As a consequence, the symmetric phenotype distribution cannot match the highly asymmetric, cliff-edged fitness distribution well: The optimal phenotype distribution that maximizes population mean fitness entails a fraction of individuals falling beyond the "fitness edge" (i.e., those with fetopelvic disproportion). Using a simple mathematical model, we show that weak directional selection for a large neonate, a narrow pelvic canal, or both is sufficient to account for the considerable incidence of fetopelvic disproportion. Based on this model, we predict that the regular use of Caesarean sections throughout the last decades has led to an evolutionary increase of fetopelvic disproportion rates by 10 to 20%.

A debate about ultrasound and anatomic aspects of the cervix in spontaneous preterm birth

Preterm birth is the legal first global cause of neonatal death. The cervix has two roles: it has to stay closed to allow the fetus to undergo a normal development during gestation, and at term, the cervix has to dilate under the pressure of uterine contractions to allow the delivery. The purpose of this article is to establish if the ultrasound measured length of the cervix and its appearance are predictive for the spontaneous preterm birth. Cervical insufficiency can be described by painless cervical dilatation leading to pregnancy losses/ births, with no other risk factors present. During gestation, the physiological softening of the cervix is determined by the extracellular matrix components, particular decorin, and thrombospondin 2. The direction of the collagen fibers remains the same - circumferential direction, but the collagen solubility increases. Therefore, during pregnancy, the cervical tissue is more hydrated and has higher collagen extractability than non-pregnant tissue. Women with cervical incompetence have increased levels of smooth muscle cells than normal pregnant women, the number of elastic fibers is low, and also the concentration of hydroxyproline is decreased. Transvaginal ultrasound is the suitable gold standard exam that can offer essential information about the cervical length and state of the internal os in early asymptomatic stage of cervical insufficiency for predicting and preventing preterm birth. In our experience, a transvaginal ultrasound screening for the measurement of the cervix is required. We consider that the proper gestational age for the prediction of a preterm birth is at 18-22 weeks of gestation for the general population and earlier for patients with a history of preterm birth. Just from an observational point of view, we concluded with the fact that the cerclage of the cervix is unnecessary if the cervical length is above 2 cm and if the internal cervical os is closed. In the absence of funneling, the probability of cervical incompetence is low and the best prophylactic option is progesterone administration.

Dynamic collagen changes in cervix during the first trimester and decreased collagen content in cervical insufficiency

OBJECTIVE

To determine the changes in cervical collagen during the first trimester of pregnancy and to evaluate the collagen deficit in cases with a previous diagnosis of cervical insufficiency (CI).

MATERIALS AND METHODS

Cervical punch biopsies were obtained from 66 patients divided into three groups: patients with recurrent abortions due to CI (CI group; n = 8); first-trimester abortion group (study group; n = 37), subdivided into three groups according their gestational week (<7, 7-9 and 9-12 weeks), and patients with cervical biopsy due to gynecologic reasons (control group; n = 12). Collagen quantity was determined by a biochemical method that measured the levels of hydroxyproline (HOP) in dry cervix tissue.

RESULTS

The HOP concentrations were significantly higher at lower gestational ages (p = 0.001). Collagen quantity was lowest in the CI group compared with other groups (p < 0.001).

CONCLUSION

This study shows collagen component of cervix decreases as pregnancy advances through the first trimester. Cervical collagen concentration is lower in women with a history of CI compared to controls who has not a history of CI.

Overview of the mechanisms of induction of labor

Here we provide a brief overview of the natural process of labor and its biochemical, hormonal, and mechanical characteristics that can be exploited in methods employed for induction of labor.

Compensatory fetal membrane mechanisms between biglycan and decorin in inflammation

Preterm premature rupture of fetal membranes (PPROM) is associated with infection, and is one of the most common causes of preterm birth. Abnormal expression of biglycan and decorin, two extracellular matrix proteoglycans, leads to preterm birth and aberrant fetal membrane morphology and signaling in the mouse. In humans and mice, decorin dysregulation is associated with inflammation in PPROM. We therefore investigated the link between biglycan and decorin and inflammation in fetal membranes using mouse models of intraperitoneal Escherichia coli injections superimposed on genetic biglycan and decorin deficiencies. We assessed outcomes in vivo as well as in vitro using quantitative PCR, Western blotting, and enzyme-linked immunosorbent assays. Our results suggest that biglycan and decorin compensate for each other in the fetal membranes, but lose the ability to do so under inflammation, leading to decreased latency to preterm birth. Furthermore, our findings suggest that biglycan and decorin play discrete roles in fetal membrane signaling pathways during inflammation, leading to changes in the abundance of MMP8 and collagen α1VI, two components of the fetal membrane extracellular matrix that influence the pathophysiology of PPROM. In summary, these findings underline the importance of biglycan and decorin as targets for the manipulation of fetal membrane extracellular matrix stability in the context of inflammation.

ADAMTS proteases in fertility

The reproductive organs are unique among adult organs in that they must undergo continual tissue remodelling as a key aspect of their normal function. The processes for persistent maturation and release of new gametes, as well as fertilisation, implantation, placentation, gestation and parturition involve cyclic development and regression of tissues that must continually regenerate to support fertility. The ADAMTS family of proteases has been shown to contribute to many aspects of the tissue morphogenesis required for development and function of each of the reproductive organs. Dysregulation or functional changes in ADAMTS family proteases have been associated with reproductive disorders such as polycystic ovarian syndrome (PCOS) and premature ovarian failure (POF). Likewise, proteolytic substrates of ADAMTS enzymes have also been linked to reproductive function. New insight into the roles of ADAMTS proteases has yielded a deeper understanding of the molecular mechanisms behind fertility with clinical potential to generate therapeutic targets to resolve infertility, develop biomarkers that predict dysfunction of the reproductive organs and potentially offer targets for development of non-hormonal male and female contraceptives.

Genomics of preterm birth

The molecular mechanisms controlling human birth timing at term, or resulting in preterm birth, have been the focus of considerable investigation, but limited insights have been gained over the past 50 years. In part, these processes have remained elusive because of divergence in reproductive strategies and physiology shown by model organisms, making extrapolation to humans uncertain. Here, we summarize the evolution of progesterone signaling and variation in pregnancy maintenance and termination. We use this comparative physiology to support the hypothesis that selective pressure on genomic loci involved in the timing of parturition have shaped human birth timing, and that these loci can be identified with comparative genomic strategies. Previous limitations imposed by divergence of mechanisms provide an important new opportunity to elucidate fundamental pathways of parturition control through increasing availability of sequenced genomes and associated reproductive physiology characteristics across diverse organisms.

Mechanical signaling in reproductive tissues: mechanisms and importance

The organs of the female reproductive system are among the most dynamic tissues in the human body, undergoing repeated cycles of growth and involution from puberty through menopause. To achieve such impressive plasticity, reproductive tissues must respond not only to soluble signals (hormones, growth factors, and cytokines) but also to physical cues (mechanical forces and osmotic stress) as well. Here, we review the mechanisms underlying the process of mechanotransduction-how signals are conveyed from the extracellular matrix that surrounds the cells of reproductive tissues to the downstream molecules and signaling pathways that coordinate the cellular adaptive response to external forces. Our objective was to examine how mechanical forces contribute significantly to physiological functions and pathogenesis in reproductive tissues. We highlight how widespread diseases of the reproductive tract, from preterm labor to tumors of the uterus and breast, result from an impairment in mechanical signaling.

Synergy and interactions among biological pathways leading to preterm premature rupture of membranes

Preterm premature rupture of membranes (PPROM) occurs in 1% to 2% of births. Impact of PPROM is greatest in low- and middle-income countries where prematurity-related deaths are most common. Recent investigations identify cytokine and matrix metalloproteinase activation, oxidative stress, and apoptosis as primary pathways to PPROM. These biological processes are initiated by heterogeneous etiologies including infection/inflammation, placental bleeding, uterine overdistention, and genetic polymorphisms. We hypothesize that pathways to PPROM overlap and act synergistically to weaken membranes. We focus our discussion on membrane composition and strength, pathways linking risk factors to membrane weakening, and future research directions to reduce the global burden of PPROM.

Risk stratification and hierarchy of antenatal care

Cardiac disease is the leading cause of maternal death in the UK. The triennial maternal mortality reports have repeatedly highlighted failure to recognise the level of risk as a major contributing factor to the deaths of these women. Once the level of risk has been recognised, services then need to be organised in a way that supports the needs of the highest risk women, but avoids unnecessary intervention for women at lower risk. Risk scoring systems and lesion-specific indicators may help predict maternal and neonatal outcomes. Care can then be planned accordingly, to optimise the outcome for the woman and her baby.

Imitating a stress response: a new hypothesis about the innate immune system's role in pregnancy

Recent research challenges long-held hypotheses about mechanisms through which pregnancy induces maternal immune suppression or tolerance of the embryo/fetus. It is now understood that normal pregnancy engages the immune system and that the immune milieu changes with advancing gestation. We suggest that pregnancy mimics the innate immune system's response to stress, causing a sterile inflammatory response that is necessary for successful reproduction. The relationship between external stressors and immunomodulation in pregnancy has been acknowledged, but the specific mechanisms are still being explicated. Implantation and the first trimester are times of immune activation and intensive inflammation in the uterine environment. A period of immune quiescence during the second trimester allows for the growth and development of the maturing fetus. Labor is also an inflammatory event. The length of gestation and timing of parturition can be influenced by environmental stressors. These stressors affect pregnancy through neuroendocrine interaction with the immune system, specifically through the hypothalamic-pituitary-adrenal (HPA) axis and the hypothalamic-pituitary-ovarian axis. Trophoblastic cells that constitute the maternal-fetal interface appear to harness the maternal immune system to promote and maximize the reproductive success of the mother and fetus. Pregnancy is a time of upregulated innate immune responses and decreased adaptive, cell-mediated responses. The inflammatory processes of pregnancy resemble an immune response to brief naturalistic stressors: there is a shift from T helper (Th) 1 to T helper (Th) 2 dominant adaptive immunity with a concomitant shift in cytokine production, decreased proliferation of T cells, and decreased cytotoxicity of natural killer (NK) cells. Inclusion of both murine and human studies, allows an exploration of insights into how trophoblasts influence the activity of the maternal innate immune system during gestation.

Marfan syndrome and pregnancy: maternal and neonatal outcomes

Objective

To report outcomes in a recent series of pregnancies in women with Marfan syndrome (MFS).

Design

Retrospective case note review.

Setting

Tertiary referral unit (Chelsea and Westminster and Royal Brompton Hospitals).

Sample

Twenty-nine pregnancies in 21 women with MFS between 1995 and 2010.

Methods

Multidisciplinary review of case records.

Main outcome measures

Maternal and neonatal mortality and morbidity of patients with MFS and healthy controls.

Results

There were no maternal deaths. Significant cardiac complications occurred in five pregnancies (17%): one woman experienced a type–A aortic dissection; two women required cardiac surgery within 6 months of delivery; and a further two women developed impaired left ventricular function during the pregnancy. Women with MFS were also more likely to have obstetric complications (OR 3.29, 95% CI 1.30–8.34), the most frequent of which was postpartum haemorrhage (OR 8.46, 95% CI 2.52–28.38). There were no perinatal deaths, although babies born to mothers with MFS were delivered significantly earlier than those born to the control group (median 39 versus 40 weeks of gestation, Mann–Whitney U–test, P = 0.04). These babies were also significantly more likely to be small for gestational age (24% in the MFS group versus 6% in the controls; OR 4.95, 95% CI 1.58–15.55).

Conclusions

Pregnancy in women with MFS continues to be associated with significant rates of maternal, fetal, and neonatal complications. Effective pre-pregnancy counselling and meticulous surveillance during pregnancy, delivery, and the puerperium by an experienced multidisciplinary team are warranted for women with MFS.