The association between vaginal bacterial composition and miscarriage: a nested case-control study.

OBJECTIVE: To characterise vaginal bacterial composition in early pregnancy and investigate its relationship with first and second trimester miscarriages. DESIGN: Nested case-control study. SETTING: Queen Charlotte's and Chelsea Hospital, Imperial College Healthcare NHS Trust, London. POPULATION: 161 pregnancies: 64 resulting in first trimester miscarriage, 14 in second trimester miscarriage and 83 term pregnancies. METHODS: Prospective profiling and comparison of vaginal bacteria composition using 16S rRNA gene-based metataxonomics from 5 weeks' gestation in pregnancies ending in miscarriage or uncomplicated term deliveries matched for age, gestation and body mass index. MAIN OUTCOME MEASURES: Relative vaginal bacteria abundance, diversity and richness. Pregnancy outcomes defined as first or second trimester miscarriage, or uncomplicated term delivery. RESULTS: First trimester miscarriage associated with reduced prevalence of Lactobacillus spp.-dominated vaginal microbiota classified using hierarchical clustering analysis (65.6 versus 87.7%; P = 0.005), higher alpha diversity (mean Inverse Simpson Index 2.5 [95% confidence interval 1.8-3.0] versus 1.5 [1.3-1.7], P = 0.003) and higher richness 25.1 (18.5-31.7) versus 16.7 (13.4-20), P = 0.017), compared with viable pregnancies. This was independent of vaginal bleeding and observable before first trimester miscarriage diagnosis (P = 0.015). Incomplete/complete miscarriage associated with higher proportions of Lactobacillus spp.-depleted communities compared with missed miscarriage. Early pregnancy vaginal bacterial stability was similar between miscarriage and term pregnancies. CONCLUSIONS: These findings associate the bacterial component of vaginal microbiota with first trimester miscarriage and indicate suboptimal community composition is established in early pregnancy. While further studies are required to elucidate the mechanism, vaginal bacterial composition may represent a modifiable risk factor for first trimester miscarriage. TWEETABLE ABSTRACT: Vaginal bacterial composition in first trimester miscarriage is associated with reduced Lactobacillus spp. abundance and is independent of vaginal bleeding.

The vaginal microbiome in uterine transplantation.

Women with congenital absolute uterine factor infertility (AUFI) often need vaginal restoration to optimise sexual function. Given their lack of procreative ability, little consideration has previously been given to the resultant vaginal microbiome (VM). Uterine transplantation (UTx) now offers the opportunity to restore these women's reproductive potential. The structure of the VM is associated with clinical and reproductive implications that are intricately intertwined with the process of UTx. Consideration of how vaginal restoration methods impact VM is now warranted and assessment of the VM in future UTx procedures is essential to understand the interrelation of the VM and clinical and reproductive outcomes. TWEETABLE ABSTRACT: The vaginal microbiome has numerous implications for clinical and reproductive outcomes in the context of uterine transplantation.

Prospective observational study of vaginal microbiota pre- and post-rescue cervical cerclage.

OBJECTIVE: To investigate the relation between vaginal microbiota composition and outcome of rescue cervical cerclage. DESIGN: Prospective observational study. SETTING: Queen Charlotte's and Chelsea Hospital, London. POPULATION: Twenty singleton pregnancies undergoing a rescue cervical cerclage. METHODS: Vaginal microbiota composition was analysed in women presenting with a dilated cervix and exposed fetal membranes before and 10 days following rescue cervical cerclage and was correlated with clinical outcomes. MAIN OUTCOME MEASURES: Composition of vaginal bacteria was characterised by culture-independent next generation sequencing. Successful cerclage was defined as that resulting in the birth of a neonate discharged from hospital without morbidity. Unsuccessful cerclage was defined as procedures culminating in miscarriage, intrauterine death, neonatal death or significant neonatal morbidity. RESULTS: Reduced Lactobacillus spp. relative abundance was observed in 40% of cases prior to rescue cerclage compared with 10% of gestation age-matched controls (8/20, 40% versus 3/30, 10%, P = 0.017). Gardnerella vaginalis was over-represented in women presenting with symptoms (3/7, 43% versus 0/13, 0%, P = 0.03, linear discriminant analysis, LDA (log 10) and cases culminating in miscarriage (3/6, 50% versus 0/14, 0%, P = 0.017). In the majority of cases (10/14, 71%) bacterial composition was unchanged following cerclage insertion and perioperative interventions. CONCLUSIONS: Reduced relative abundance of Lactobacillus spp. is associated with premature cervical dilation, whereas high levels of G. vaginalis are associated with unsuccessful rescue cerclage cases. The insertion of a rescue cerclage does not affect the underlying bacterial composition in the majority of cases. TWEETABLE ABSTRACT: Preterm cervical dilatation associates with reduced Lactobacillus spp. Presence of Gardnerella vaginalis predicts rescue cerclage failure.

Preconception and early pregnancy maternal haemodynamic changes in healthy women in relation to pregnancy viability.

STUDY QUESTION: Are there differences in preconception cardiovascular function between women who have a viable pregnancy and those who have a first trimester miscarriage? SUMMARY ANSWER: Preconception cardiovascular function of central haemodynamics and arterial function are similar between women who have a viable pregnancy and those who have a first trimester miscarriage. WHAT IS KNOWN ALREADY: Miscarriages have been associated with increased long-term cardiovascular disease risk, and arterial and cardiovascular dysfunction has been hypothesised as the common link. It is not known if these risks are present prior to pregnancy or are a reflection of poor arterial and haemodynamic adaptation to pregnancy. STUDY DESIGN, SIZE, DURATION: This prospective longitudinal preconception cohort study was conducted over 18 months. In total, 367 participants were recruited pre-pregnancy, from which 197 pregnancies were recorded; 39 of these pregnancies ended in first trimester miscarriage. Complete longitudinal data were available for 172 pregnancies (140 viable pregnancies, 32 first trimester miscarriages) from pre-pregnancy to 6 weeks gestation. PARTICIPANTS/MATERIALS, SETTING, METHODS: This was a single site study based at a maternity hospital in London. Healthy women were recruited prior to natural conception and followed up once they became pregnant. All underwent haemodynamic [cardiac output (CO), peripheral vascular resistance (PVR)] and arterial function [aortic augmentation index (AIx) and pulse wave velocity (PWV)] testing prior to pregnancy and at 6 weeks gestation, using non-invasive devices (gas re-breathing method, Innocor® and an occilometric device, Vicorder®). Cross-sectional measurements at pre-pregnancy and 6 weeks gestation and a longitudinal analysis of changes were compared between women who had a subsequent viable pregnancy, and those who had a subsequent first trimester miscarriage. MAIN RESULTS AND THE ROLE OF CHANCE: There were no differences between women destined to have a healthy ongoing pregnancy compared to those who miscarried, in terms of baseline cardiovascular function, assessed by CO, PVR, PWV or AIx. Similarly, between the groups, there were no differences in pregnancy adaptation with similar trends in cardiovascular function changes from pre-pregnancy to 6 weeks gestation. LIMITATIONS, REASONS FOR CAUTION: Whilst this is the first study to investigate preconception and early pregnancy haemodynamic and arterial function in relation to viability, the relatively modest number of miscarriages may not be sufficient to show subtle differences in haemodynamic changes if these were present. WIDER IMPLICATIONS OF THE FINDINGS: This study suggests that pre-pregnancy haemodynamic and arterial function is unlikely to be the causal link between miscarriages and future cardiovascular disease. Our findings suggests that factors other than the presence of a viable embryo drive cardiovascular changes in early pregnancy. This study raises new questions about miscarriages as an independent risk event which predisposes women to increased cardiovascular risk later in life. STUDY FUNDING/COMPETING INTEREST(S): The investigators are funded by NIHR Imperial BRC, NIHR Cambridge BRC, Action Medical Research, Imperial College Healthcare Charity and Tommy's Charity. We acknowledge the loan of ultrasound equipment from Samsung Medison (South Korea)/MIS Ltd and provision of fertility monitors from SPD Development Company Ltd (Bedford, UK). There are no competing interests. C.C.L. is supported by the UK National Institute for Health Research Biomedical Research Centre based at Imperial College Healthcare National Health Service Trust and Imperial College London. TRIAL REGISTRATION NUMBER: N/A.

Safety, tolerability, and acceptability of Lactobacillus crispatus CTV-05 (LACTIN-V) in pregnant women at high-risk of preterm birth.

The vaginal microbiota is a determinant for the risk of preterm birth (PTB). Dominance of the vaginal niche by Lactobacillus crispatus associates with term delivery. This is the first observational clinical study of live vaginal biotherapeutics (Lactobacillus crispatus CTV-05 (LACTIN-V)) in pregnant women at high-risk of PTB. The primary aim was to explore safety, tolerability and acceptability of LACTIN-V in pregnancy. Women were offered a course of LACTIN-V at 14 weeks gestation for five consecutive days followed by weekly administration for six weeks. Participants were followed up at 15, 18-, 20-, 28- and 36-weeks' gestation and at delivery for assessment of adverse events, compliance and tolerability. Participants completed a questionnaire to gauge experience and acceptability. In total, 73 women were recruited, of whom eight withdrew, leaving a final cohort size of 61. Self-reported compliance to the course was high (56/60, 93%). Solicited adverse events were reported in 13 women (19%) including changes in vaginal discharge, odour, colour or consistency of urine, itching and vaginal bleeding. One unsolicited adverse event was reported as haematuria at 38 weeks gestation, but was judged to be unrelated to LACTIN-V. No serious adverse events occurred. One mild adverse event led to study withdrawal. Thirty-one women completed an experience and acceptability questionnaire. Women found LACTIN-V easy and comfortable to use and the majority (30/31, 97%) would use LACTIN-V in future pregnancies. Eight women (8/31, 26%) found the schedule of use difficult to remember. The rate of PTB <34 weeks in this cohort was 3.3% compared to 7% in a historical cohort of 2,190 women at similar background PTB risk. With satisfactory uptake and good compliance, we demonstrate that LACTIN-V is safe and accepted in pregnancy, with high tolerability. Further studies are needed to assess colonisation of Lactobacillus crispatus CTV-05 and clinical efficacy.

Prostaglandin E2 vaginal gel or tablets for the induction of labour at term: a randomised controlled trial.

OBJECTIVE: To compare the effectiveness of prostaglandin E2 (dinopristone) vaginal gel versus vaginal tablets for the induction of labour at term. DESIGN: Randomised controlled clinical trial. SETTING: University maternity hospital in London. POPULATION: Pregnant women with cephalic presentation undergoing induction of labour after 37 weeks of gestation. METHODS: Prostaglandin E2 vaginal tablets (3 mg) or vaginal gel (1 mg/ 2 mg) was administered at 6-hourly intervals until the cervix was suitable for amniotomy. MAIN OUTCOME MEASURES: Induction to delivery interval, in minutes; rate of failed induction of labour requiring caesarean delivery. RESULTS: Eighty-two women received prostaglandin gel; 83 women received vaginal tablets. There were significant differences between the two treatment groups in the primary outcomes. The mean induction to delivery interval was significantly shorter in women who received the gel (1400 minutes, 690-2280 minutes, versus 1780 minutes, 960-2640 minutes; P = 0.03). The rate of failed induction of labour was significantly higher in women who received tablets (10.84 versus 1.22%; P = 0.01). Subanalysis showed that these differences were only representative of differences in the groups of primigravid women. There were no significant differences in any of the secondary outcomes, including the number of women who required syntocinon augmentation, the rate of uterine hyperstimulation, the need for epidural analgesia, meconium staining of liquor, the need for fetal blood sampling, or delivery by caesarean section. There were no differences in adverse maternal and neonatal outcomes. CONCLUSION: Prostaglandin E2 vaginal gel is superior to vaginal tablets for the induction of labour.

Prostaglandin F2-alpha receptor regulation in human uterine myocytes.

Investigations of the modulation of prostaglandin F(2alpha) receptor (FP) expression in primary cultures of human uterine myocytes showed that FP mRNA expression was reduced by progesterone, unaltered by cAMP (8-bromo cAMP or forskolin), but increased by the PKA antagonist H89. Interleukin (IL)-1beta, tumour necrosis factor-alpha and oxytocin increased FP mRNA expression and IL-6 and prostaglandin E(2) reduced FP mRNA expression. The changes in FP protein levels were similar to the mRNA responses. We found that the IL-1beta-induced increase in FP expression was mediated at least in part via protein kinase C (PKC), but was independent of mitogen-activated protein kinase, phospholipase C and PI3 kinase. Since IL-1beta activates NFkappaB, AP-1 and C/EBP, we over-expressed these transcription factors alone and in combination and found that only NFkappaB alone increased FP mRNA expression. Finally, we found that the IL-1beta-induced increase in FP expression was unaffected by progesterone and/or cAMP, but was accentuated by H89. These data suggest that the pregnancy-induced down-regulation in myometrial FP expression is mediated by progesterone and cAMP and that the increase with labour is induced by inflammatory cytokine activation of PKC and NFkappaB.

The mitogen-activated protein kinase dependent expression of prostaglandin H synthase-2 and interleukin-8 messenger ribonucleic acid by myometrial cells: the differential effect of stretch and interleukin-1{beta}.

Infection and uterine stretch are the common causes of preterm labor. IL-1beta plays a key role in infection-induced preterm labor and increases prostaglandin H synthase 2 (PGHS-2) and IL-8 expression. We have shown that mechanical stretch of uterine myocytes in vitro up-regulates the expression of PGHS-2 and IL-8. In this study, we tested the hypotheses that both IL-1beta and mechanical stretch increase the myometrial expression of PGHS-2 and IL-8 via MAPK activation and that their effects are synergistic. MAPK activation was assessed in myocytes obtained from pregnant women undergoing cesarean section before the onset of labor after exposure to IL-1beta and stretch either alone or in combination. Specific inhibitors of ERK, p38, and c-Jun N-terminal kinase were used to define the role of each in the increased expression of PGHS-2 and IL-8 mRNA. We found that both IL-1beta and stretch activated all three MAPK subtypes but that they had no synergistic effect. The inhibitor studies showed that stretch-induced increases in both PGHS-2 and IL-8 mRNA expression were ERK1/2 and p38 dependent and that IL-1beta-induced increases of PGHS-2 mRNA expression were also ERK1/2 and p38 dependent, but those of IL-8 were dependent only on ERK1/2 activation. These data show that exposure of human uterine myocytes to both stretch and IL-1beta activates the MAPK system, which is responsible for the increase in PGHS-2 and IL-8 mRNA expression. We found no evidence of a synergistic effect of IL-1beta and stretch on myometrial expression of PGHS-2 and IL-8 mRNA.

Progesterone and the Repression of Myometrial Inflammation: The Roles of MKP-1 and the AP-1 System.

Progesterone (P4) maintains uterine quiescence during pregnancy and its functional withdrawal is associated with increased prostaglandin synthesis and the onset of labor. In primary human myometrial cells, the glucocorticoid receptor (GR) rather than the P4 receptor mediates P4 antagonism of IL-1ß-induced cyclooxygenase-2 (COX-2) expression, the rate-limiting enzyme in prostaglandin synthesis. We now report that P4 also acts via GR to induce MAPK phosphatase (MKP)-1 and knockdown of MKP-1 impairs the ability of P4 to repress IL-1ß-dependent COX-2 induction. Microarray analysis revealed that P4 repressed preferentially activator protein-1-responsive genes in response to IL-1ß. Consistent with these observations, we found that the ability of P4 to reduce c-Jun activation was lost upon GR as well as MKP-1 knockdown. Interestingly, c-Jun levels in human myometrial cells declined upon GR and MKP-1 knockdown, which suggests the presence of an activator protein-1 feedback loop. This is supported by our observation that c-Jun levels declined after an initial rise in primary myometrial cells treated with phorbol 12-myrisatate 13-acetate, a potent activator of c-Jun N-terminal kinase. Finally, we show that MKP-1 is an intermediate in P4-mediated repression of some but not all IL-1ß-responsive genes. For example, P4 repression of IL11 and IRAK3 was maintained upon MKP-1 knockdown. Taken together, the data show that P4 acts via GR to drive MKP-1 expression, which in turn inhibits IL-1ß-dependent c-Jun activation and COX-2 expression.

Cervical intraepithelial neoplasia disease progression is associated with increased vaginal microbiome diversity.

Persistent infection with oncogenic Human Papillomavirus (HPV) is necessary for cervical carcinogenesis. Although evidence suggests that the vaginal microbiome plays a functional role in the persistence or regression of HPV infections, this has yet to be described in women with cervical intra-epithelial neoplasia (CIN). We hypothesised that increasing microbiome diversity is associated with increasing CIN severity. llumina MiSeq sequencing of 16S rRNA gene amplicons was used to characterise the vaginal microbiota of women with low-grade squamous intra-epithelial lesions (LSIL; n = 52), high-grade (HSIL; n = 92), invasive cervical cancer (ICC; n = 5) and healthy controls (n = 20). Hierarchical clustering analysis revealed an increased prevalence of microbiomes characterised by high-diversity and low levels of Lactobacillus spp. (community state type-CST IV) with increasing disease severity, irrespective of HPV status (Normal = 2/20,10%; LSIL = 11/52,21%; HSIL = 25/92,27%; ICC = 2/5,40%). Increasing disease severity was associated with decreasing relative abundance of Lactobacillus spp. The vaginal microbiome in HSIL was characterised by higher levels of Sneathia sanguinegens (P < 0.01), Anaerococcus tetradius (P < 0.05) and Peptostreptococcus anaerobius (P < 0.05) and lower levels of Lactobacillus jensenii (P < 0.01) compared to LSIL. Our results suggest advancing CIN disease severity is associated with increasing vaginal microbiota diversity and may be involved in regulating viral persistence and disease progression.

Effect of nimesulide and indomethacin on contractility and the Ca2+ channel current in myometrial smooth muscle from pregnant women.

The non-steroidal anti-inflammatory drug (NSAID) indomethacin inhibits both constitutive and inducible forms of cyclo-oxygenase (COX-1 and COX-2, respectively), while nimesulide is a selective COX-2 inhibitor. Uterine COX-2 is upregulated before and during term and pre-term labour, and prostaglandins play a crucial role in parturition. We therefore evaluated the effects of these drugs on myometrial contractility and the voltage-gated Ca2+ channel current in tissue strips and isolated human myometrial smooth muscle cells (HMSMC) from myometrial biopsies taken with informed consent from women undergoing caesarean section at term (not in labour). Nimesulide and indomethacin caused almost complete inhibition of spontaneous myometrial contractions at concentrations of 100 and 300 microM, respectively. The Ca2+ channel current was inhibited in a concentration-dependent manner by both drugs, with a 40% reduction of the current at 100 microM nimesulide and 300 microM indomethacin. Nimesulide also accelerated the decay of the Ca2+ channel current. The inhibition of the Ca2+ channel current by 100 microM nimesulide and 300 microM indomethacin was unaffected by the presence of either PGF2alpha or PGE2 (30 microM), and was of similar magnitude whether 10 mM Ba2+ or 1.5 mM Ca2+ was used as the charge carrier. The concentrations of indomethacin and nimesulide required to suppress spontaneous contractility in human pregnant myometrium were much higher than those necessary to inhibit prostaglandin production. The results suggest that both nimesulide and indomethacin inhibit myometrial contractility via mechanisms independent of cyclo-oxygenase inhibition. Blockade of the Ca2+ current may contribute to this effect.

Regulation of prostaglandin production in intact fetal membranes by interleukin-1 and its receptor antagonist.

There is strong evidence for the involvement of inflammatory mediators such as interleukin (IL)-1 in the biochemical mechanisms of parturition. Therefore the effects of the IL-1 family (IL-1alpha (1 ng/ml), IL-1beta (1 ng/ml) and the IL-1 receptor antagonist (IL-1ra) (10 ng/ml)) on the regulation of prostaglandin synthesis in term human fetal membranes were investigated. It was found that, after 4 h of culture, IL-1beta increased prostaglandin E2 (PGE2) output approximately twofold. This was associated with both a significant increase in cyclo-oxygenase-2 (COX-2) mRNA levels (approximately fourfold compared with control) and translocation of cytoplasmic phospholipase A2 (cPLA2) from the cytosol to the membrane fraction. IL-1alpha was less effective than IL-1beta at stimulating PGE2 production through similar mechanisms. IL-1ra had no effect on PGE2 output. However, in combination treatments, IL-1ra did not inhibit IL-1alpha- or IL-1beta-stimulated PGE2 output, and increased PGE2 production further compared with IL-1beta alone. IL-1ra decreased IL-1beta-induced COX-2 mRNA expression by about half and significantly increased cPLA2 protein levels, as detected by immunoblotting, when used alone and together with IL-1beta. These results suggest that IL-1ra has partial agonist properties when used together with IL-1alpha and IL-1beta in fetal membranes by increasing cPLA2 protein levels, which leads to an increase in the production of prostaglandins.

A spontaneous induction of fetal membrane prostaglandin production precedes clinical labour.

Fetal membranes from term human pregnancies produce prostaglandins, and may respond to bacterial endotoxin or interleukin-1 beta (IL-1 beta) with increased prostaglandin E2 (PGE2) production. The effects of endotoxin persisted for up to 24 h, whereas those of IL-1 beta were maximal 4-8 h after addition. The maximum levels of PGE2 (200-350 pg/ml) were similar in all experiments, and were independent of the stimulus used. Not all tissues responded to these stimuli; those which did not had basal levels of PGE2 production of 200-350 pg/ml, which was not further increased by endotoxin or IL-1 beta. The basal production from these tissues was therefore similar to the maximal production from those tissues which responded to endotoxin or IL-1 beta. The high basal production of PGE2 was attributed to prior in vivo activation of the membranes such that PGE2 synthesis could not be further stimulated in vitro. Overnight pretreatment with aspirin decreased basal PGE2 production from these activated membranes to < 100 pg/ml/4 h during subsequent culture in aspirin-free medium. Both endotoxin and IL-1 beta increased PGE2 production from the activated aspirin-pretreated membranes during this culture time, but this was transient as after 12 h of culture basal PGE2 production rose to over 200 pg/ml despite aspirin pretreatment.

The roles of the cyclo-oxygenases types one and two in prostaglandin synthesis in human fetal membranes at term.

UNLABELLED: The aim of this study was to determine the relative contributions of cyclo-oxygenase (COX) types 1 and 2 to prostaglandin synthesis at term. METHODS: Fetal membranes were collected from 6 pregnancies after elective caesarean section at term, prior to labour. The presence of COX-1 and COX-2 protein was determined using Western analysis. The relative contributions of the two isoforms of COX to prostaglandin synthesis were determined by incubation of fetal membrane discs with either a COX-2 selective inhibitor, SC236, or a COX-1 selective inhibitor, SC560, and measurement of prostaglandin release during 24 h using enzyme-linked immuno-sorbent assay (ELISA). RESULTS: Both COX-1 and COX-2 protein were demonstrated in amnion and chorion-decidua. The COX-2 selective inhibitor, SC-236, significantly reduced prostaglandin synthesis, both in its COX-2 specific and higher, non-specific concentration ranges. The COX-1 selective inhibitor, SC-560, had no effect upon prostaglandin synthesis in its COX-1 specific concentration range, but did significantly reduce prostaglandin synthesis at higher, non-selective concentrations. CONCLUSIONS: Fetal membranes contain both COX-1 and COX-2 at term, but only COX-2 contributes towards prostaglandin synthesis. COX-2 selective NSAI drugs will be as effective as non-selective agents in inhibition of fetal membrane prostaglandin synthesis and may represent a new strategy for tocolysis.

Interleukin-1beta and bacterial endotoxin change the metabolism of prostaglandins E2 and F2alpha in intact term fetal membranes.

There is strong evidence that prostaglandins E2 and F2alpha (PGE2 and PGF2alpha) are involved in the initiation and maintenance of human parturition and that their production can be stimulated by a number of cytokines and in infection-induced preterm labour by bacterial endotoxin. This study used an intact fetal membrane disk model to investigate the regulation of PGE2 and PGF2alpha metabolism by interleukin-1 beta (IL-1beta) and bacterial endotoxin [lipopolysaccharide (LPS)]. Fetal membrane explants were incubated with IL-1beta (0.1 or 1.0 ng/ml) or LPS (10 ng/ml) for 24 h. A mixture of 3H-prostaglandin (0.1 microCi) and unlabelled prostaglandin (1 microg) was then added at selected times after the addition of inflammatory mediators. The radiolabelled prostaglandins and their metabolites were then extracted from the culture medium and quantified by high-pressure liquid chromatography. Levels of prostaglandin metabolites were generally decreased following incubation with IL-1beta or LPS, which is consistent with a decrease in the activity of 15-hydroxyprostaglandin dehydrogenase (PGDH). It is concluded that IL-1beta and LPS moderately decrease the metabolism of prostaglandins, which may contribute to increasing the local levels of active prostaglandins induced by these stimuli.

Stimulation of prostaglandin production from intact human fetal membranes by bacteria and bacterial products.

The addition of live or sonicated Escherichia coli, or endotoxin from E. coli increased the release of prostaglandins (PG) on both sides of intact human fetal membranes after 24 h of incubation, indicating that live bacteria were not required to activate prostaglandin production. Time-course studies showed that the levels of PGE2 and PGF2alpha on the fetal side of the membrane were increased 6 h after the addition of endotoxin, whereas levels on the maternal side increased within 1-2 h. These changes were independent of the side to which the endotoxin was added, indicating that a stimulatory factor passes through the fetal membranes. This factor is not endotoxin, which did not cross the membranes, and further studies are required to identify this endogenous stimulus. Prostaglandin metabolite levels were either unaffected or increased by endotoxin, indicating that the main effect is at the level of increased prostaglandin biosynthesis rather than decreased metabolism.

Region and labour-dependent synthesis of prostaglandin E2 by human fetal membranes.

To examine the effect of region and labour upon prostaglandin synthesis in human fetal membranes, intact membranes from three regions, the cervical region, the periplacental region and a region midway between the two, were collected following spontaneous labour and delivery or at elective caesarean section prior to labour. Discs of 2-cm diameter were cut from each of three regions and incubated for 1, 2, 4, 6, 12 or 24 h after which prostaglandin E2 concentration in the supernatant was measured. We found that there was an overall decrease in prostaglandin synthesis in tissues collected after labour, but that this effect could be reversed if exogenous arachidonic acid substrate was supplied. We found no differences in prostaglandin synthesis between tissues collected from each of the three regions. We conclude that prostaglandin synthesis from the fetal membranes during labour leads to depletion of arachidonic acid substrate and that regional changes in prostaglandin dehydrogenase activity do not appear to have a significant effect upon overall prostaglandin synthesis.

Amiodarone given by three routes to terminate fetal atrial flutter associated with severe hydrops.

BACKGROUND: We describe the concurrent administration of amiodarone using three different routes in order to provide: 1) rapid and adequate fetal loading without giving unduly high doses to the mother, and 2) a maintenance dose to the fetus without risking repeated invasive procedures. CASE: Rapid atrial flutter was seen on ultrasound in a fetus with severe hydrops at 27 weeks' gestation. Following failed transplacental therapy with sotalol and flecainide, amiodarone was administered to the fetus via the intravenous, intraperitoneal, and transplacental routes. Conversion to sinus rhythm and resolution of hydrops followed this treatment. CONCLUSION: Combined triple-route administration of amiodarone to the fetus can be effective in treating supraventricular tachycardia and may have a role in the management of life-threatening fetal arrhythmias refractory to transplacental therapy.

Progesterone receptor isoform A inhibits isoform B-mediated transactivation in human amnion.

Human amnion cells were transfected with progesterone receptor A and/or B, and the progesterone-dependent reporter construct, mouse mammary tumor virus promoter (MMTV), linked to a luciferase gene. In progesterone receptor B-expressing amnion that had been cultured before the onset of labour, treatment with progesterone resulted in an eightfold increase of the reporter activity, whereas in laboured cells, no such increase was seen. In contrast, progesterone receptor A was a weak activator of transcription in laboured and non-laboured amniocytes. When the isoforms A and B of the progesterone receptor were co-transfected, progesterone receptor A exhibited a marked inhibitory effect on progesterone receptor B-mediated transcription. These results show that progesterone receptors A and B function differentially, and progesterone receptor A is a transdominant repressor of progesterone receptor B-mediated transcription in human term amnion.

Uterine stretch and progesterone action.

CONTEXT: Progesterone administration reduces the risk of preterm labor in high-risk women with singleton pregnancies but has no effect in women with a multiple pregnancy. OBJECTIVE: We investigated whether progesterone is able to inhibit stretch-induced gene expression and/or whether stretch in turn inhibits progesterone action, perhaps providing an explanation for the functional progesterone withdrawal associated with human labor. METHODS AND RESULTS: In a series of in vitro studies using primary cultures of human myometrial cells, we found that preincubation with progesterone did not block stretch-induced ERK1/2 activation and cyclooxygenase-2 mRNA expression. Furthermore, we found that stretch did not alter the ability of progesterone to: 1) modulate progesterone-responsive gene expression; 2) activate a luciferase-linked progesterone response element; or 3) repress IL-1ß-driven cyclooxygenase-2 mRNA expression. We did find that stretch reduced the expression of progesterone receptor mRNA via nuclear factor κB activation but that this did not alter myometrial progesterone response. CONCLUSION: These data show that progesterone does not inhibit stretch-induced MAPK activation or gene expression, possibly explaining why progesterone is ineffective in the prevention of preterm labor in multiple pregnancy. Although stretch did reduce progesterone receptor expression in a nuclear factor κB-dependent manner, this was not sufficient to inhibit progesterone action, suggesting that it is not responsible for the functional progesterone withdrawal observed with the onset of human labor.