Involvement of oxytocin and vasopressin in the pathophysiology of preterm labor and primary dysmenorrhea

Effects of atosiban on clinical outcome in frozen-thawed embryo transfer: a propensity score matching study

PURPOSE

To evaluate the effects of atosiban on clinical outcomes in patients undergoing frozen-thawed embryo transfer.

METHODS

The clinical data of 1093 infertile patients who underwent frozen-thawed embryo transfer in our center from January 2019 to December 2020 were retrospectively analyzed (control, 418; atosiban, 675). Propensity score matching (PSM) analysis identified 400 matched pairs of patients. The implantation rate, clinical pregnancy rate, live birth rate, biochemical pregnancy rate, abortion rate, multiple pregnancy rate, and ectopic pregnancy rate between the two groups were compared.

RESULTS

Before PSM, patients differed by infertility factors, number of transferred embryos, and endometrial preparation protocol (P < 0.05). After PSM, characteristics were similar in corresponding patients of the atosiban and control groups. After propensity score matching, we found that there was no significant difference in the implantation rate, clinical pregnancy rate, live birth rate, biochemical pregnancy rate, abortion rate, multiple pregnancy rate, and ectopic pregnancy rate in atosiban and control group (P > 0.05).

CONCLUSION

Atosiban did not improve the clinical outcomes of infertile patients with frozen-thawed embryo transfer.

Repurposing of Bryophyllum pinnatum for dysmenorrhea treatment: a systematic scoping review and case series

Dysmenorrhea affects women throughout their reproductive years but there has been a lack of effective and well-tolerated treatment options. Pain symptoms mainly result from inflammatory processes and increased contractile activity in the myometrium. The reported use of Bryophyllum pinnatum preparations against inflammation and pain in ethnomedicine as well as current pharmacological data on their inhibition of myometrial contractility led us to hypothesize that this medicinal plant might be a new treatment option for dysmenorrhea. In the first part of the present work, clinical, in vivo, and in vitro studies on the anti-nociceptive and anti-inflammatory, as well as on myometrium relaxing properties of B. pinnatum are reviewed. In the second part, cases of five women with dysmenorrhea who were tentatively treated with a B. pinnatum product are described. The review revealed thirty-three experimental in vivo and in vitro studies, but no clinical study, reporting anti-nociceptive and anti-inflammatory effects of B. pinnatum extracts and compounds in a wide range of conditions. Moreover, sixteen publications on smooth muscle contractility revealed relaxing effects. The latter consisted of clinical evidence, as well as of in vivo and in vitro data. The evidence reviewed therefore provided a rational basis for the use of B. pinnatum in the treatment of dysmenorrhea. We subsequently set out to tentatively treat patients with a well-tolerated B. pinnatum product that is registered (without indication) and commonly used in obstetrics and gynecology in Switzerland. All five treated patients reported a reduction in pain symptoms and 4 out of 5 indicated a reduced intake of painkillers during menstruation. Taken together, the reviewed information on the pharmacological properties and clinical evidence of B. pinnatum extracts and compounds as well as the outcomes of all five patients in the case series support our hypothesis in favor of B. pinnatum as a new, well-tolerated therapeutic approach for dysmenorrhea. Prospective clinical studies are urgently needed.

Insight into Dysmenorrhea Research from 1992 to 2022: A Bibliometric Analysis

Dysmenorrhea, classified as primary dysmenorrhea and secondary dysmenorrhea, is a common gynecological symptom that seriously affects female daily life. At present, studies on dysmenorrhea are numerous and complex. To better reflect the trend and innovative progress of dysmenorrhea-related research, this study screened papers on the Web of Science from January 1, 1992, to December 31, 2022. A total of 1012 papers were selected and analyzed for their affiliated countries, institutions, authors, keywords, etc. China is the country with the most academic output, Beijing University of Traditional Chinese Medicine is the most influential institution, and Yang Jie, from Chengdu University of Traditional Chinese Medicine, China, is the scholar with the most papers. We consider that the current research focus is on pathogenesis, treatment, epidemiology, and self-management. With increasing research on functional connectivity between dysmenorrhea and various brain regions, functional connectivity has gradually become the forefront of research. We hope our study can promote the further study of dysmenorrhea.

Effectiveness of atosiban in women with previous single implantation failure undergoing frozen-thawed blastocyst transfer: study protocol for a randomised controlled trial

BACKGROUND

Uterine contractions may interfere with embryo implantation in assisted reproductive technology. To reduce these contractions and improve success rates, the oxytocin antagonist atosiban has been suggested for administration during embryo transfer. The aim of this study is to evaluate the effectiveness of atosiban in increasing live birth rates among women who have previously experienced a single implantation failure and are scheduled for single blastocyst transfer.

METHODS AND ANALYSIS

We conduct a single-centre randomised controlled study comparing atosiban and placebo in women undergoing a single blastocyst transfer with a previous failed blastocyst transfer. Women with endocrine or systemic illnesses, recurrent miscarriages, uterine malformations or fibroids, untreated hydrosalpinx, endometriosis (stage III or IV) or uterine fibroids, as well as women undergoing preimplantation genetic testing, are ineligible. The primary outcome is live birth resulting from the frozen-thawed embryo transfer. Secondary outcomes include biochemical/clinical pregnancy, miscarriage, ectopic pregnancy, multiple pregnancies as well as maternal and perinatal outcomes. We plan to recruit 1100 women (550 women per group). This will allow us to demonstrate or refute an increase in live birth rate from 40% to 50%. Data analysis will follow the intention-to-treat principle. We will measure patterns of uterine peristalsis which will allow subgroup analysis for women with or without uterine peristalsis.

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board of Northwest Women's and Children's Hospital (No. SZ2019001). Written informed consent will be obtained from each participant before randomisation. The results of the trial will be presented at scientific meetings and reported in publications.

TRIAL REGISTRATION NUMBER

ChiCTR1900022333.

The Association of Reproductive Hormones During the Menstrual Period with Primary Dysmenorrhea

Objective

This study aimed to investigate the association of reproductive hormones with primary dysmenorrhea in Chinese women.

Methods

A case-control study was conducted and patients with primary dysmenorrhea and non-dysmenorrhea participants were recruited. Oxytocin, PGF2α, vasopressin, estriol and estradiol were respectively measured in plasma collected three to five days after menstruation. Restricted cubic spline and multiple logistic regression models were adopted to analyze the association between hormones and primary dysmenorrhea.

Results

There were 604 participants enrolled in our study including 300 patients with primary dysmenorrhea. After adjustment for the potential confounders, oxytocin levels (Q3: OR (95% CI) = 0.50 (0.27~0.95) (p=0.035); Q4: 0.34 (0.17~0.66) (p=0.001)) and PGF2α levels (Q3: 0.45 (0.24~0.87) (p=0.017); Q4: 0.43 (0.22~0.84) (p=0.013)) were respectively associated with an decreased risk of primary dysmenorrhea, but estradiol (Q2: 2.18 (1.13~4.19) (p=0.020); Q3: 2.17 (1.12~4.19) (p=0.022)) and vasopressin (Q3: 2.88 (1.48~5.63) (p=0.002); Q4: 3.20 (1.65~6.22) (p<0.001)) with an increased risk of primary dysmenorrhea, respectively. Among patients with primary dysmenorrhea, the higher estriol level was associated with higher frequent dysmenorrhea (Q2: 3.12 (1.32~7.34) (p=0.009); Q3: 4.97 (2.08~11.85) (p<0.001)) and always dysmenorrhea (Q2: 2.51 (1.03~6.11) (p=0.041); Q3: 3.10 (1.25~7.73) (p=0.015)). Similarly, high estriol levels were associated with the higher degree of pain significantly only when hormone levels were at a high level (Q3: 2.06 (1.03~4.18) (p=0.043)).

Conclusion

Higher serum vasopressin and estradiol concentrations as well as lower oxytocin and PGF2α levels were associated with higher risk of primary dysmenorrhea. Estrogen showed a reverse U-shape association on the frequency and degree of pain among patients with primary dysmenorrhea.

RISING STARS: The heat is on: how does heat exposure cause pregnancy complications?

The incidence and severity of heatwaves are increasing globally with concomitant health complications. Pregnancy is a critical time in the life course at risk of adverse health outcomes due to heat exposure. Dynamic physiological adaptations, which include altered thermoregulatory pathways, occur in pregnancy. If heat dissipation is ineffective, maternal and neonate health outcomes can be compromised. Indeed, epidemiological studies and animal models reveal that exposure to heat in pregnancy likely elicits an array of health complications including miscarriage, congenital anomalies, low birth weight, stillbirth, and preterm birth. Despite these associations, the reasons for why these complications occur are unclear. An array of physiological and endocrine changes in response to heat exposure in pregnancy likely underpin the adverse health outcomes, but currently, conclusive evidence is sparse. Accompanying these fundamental gaps in knowledge is a poor understanding of what exact climatic conditions challenge pregnant physiology. Moreover, the overlay of thermoregulatory-associated behaviours such as physical activity needs to be taken into consideration when assessing the risks to human health and identifying critical populations at risk. While the health impacts from heat are largely preventable through strategic interventions, for the related clinical practice, public health, and policy approaches to be effective, the gaps in basic science understanding urgently need to be addressed.

Structures of the arginine-vasopressin and oxytocin receptor signaling complexes

Arginine-vasopressin (AVP) and oxytocin (OT) are neurohypophysial hormones which share a high sequence and structure homology. These are two cyclic C-terminally amidated nonapeptides with different residues at position 3 and 8. In mammals, AVP and OT exert their multiple biological functions through a specific G protein-coupled receptor family: four receptors are identified, the V1a, V1b, V2 receptors (V1aR, V1bR and V2R) and the OT receptor (OTR). The chemical structure of AVP and OT was elucidated in the early 1950s. Thanks to X-ray crystallography and cryo-electron microscopy, it took however 70 additional years to determine the three-dimensional structures of the OTR and the V2R in complex with their natural agonist ligands and with different signaling partners, G proteins and β-arrestins. Today, the comparison of the different AVP/OT receptor structures gives structural insights into their orthosteric ligand binding pocket, their molecular mechanisms of activation, and their interfaces with canonical Gs, Gq and β-arrestin proteins. It also paves the way to future rational drug design and therapeutic compound development. Indeed, agonist, antagonist, biased agonist, or pharmacological chaperone analogues of AVP and OT are promising candidates to regulate different physiological functions and treat several pathologies.

Uncovering the effects and mechanism of Danggui Shaoyao San intervention on primary dysmenorrhea by serum metabolomics approach

Danggui Shaoyao San (DSS) is a well-known prescription for relieving primary dysmenorrhea (PD) of women in China. However, its pharmacological mechanism has not been thoroughly uncovered. Here, an integrative UPLC-Q-TOF-MS-based serum metabolomics approach coupled with multivariate data analysis has been proposed to investigate the effects and mechanism of DSS on estradiol benzoate and oxytocin-induced PD rats. 31 potential biomarkers of PD were screened and identified, mainly involving phenylalanine, tyrosine and tryptophan biosynthesis, glycerophospholipid metabolism, primary bile acid biosynthesis, and the occurrence of PD could destroy biological homeostasis in vivo by monitoring these pathways. After DSS treatment, 18 identified different metabolites were restored to the nomal state in varying degrees and could be potential biomarkers contributing to the treatment of DSS. These findings implyed that DSS exhibited a therapeutic effect on PD rats through regulating multiple abnormal pathways. Of note, this study discovered some potential biomarkers related to PD for the first time, such as L-tyrosine, glycocholic acid, citric acid, palmitoylcarnitine, cholesterol. It preliminarily proved the pathophysiology of PD and action mechanisms of DSS on PD, and provided a novel insight into the effectiveness of DSS on PD.

Lippia origanoides essential oil induces tocolytic effect in virgin rat uterus and inhibits writhing in a dysmenorrhea mouse model

ETHNOPHARMACOLOGICAL RELEVANCE

The species Lippia origanoides Kunth, popularly known as "salva-de-marajó", is used in Brazilian traditional "quilombola" communities to treat menstrual cramps and uterine inflammation.

AIM OF THE STUDY

Evaluate the spasmolytic activity of Lippia origanoides essential oil (LOO) on experimental models of uterine conditions related to menstrual cramps and investigate its mechanism of action.

MATERIALS AND METHODS

Virgin rat-isolated uterus was mounted in the organ bath apparatus to evaluate the spasmolytic effect of LOO on basal tonus and contractions induced by carbachol, KCl, or oxytocin. We used pharmacological agents to verify the relaxation mechanism of LOO. The evaluation of uterine contractility in virgin rats, after treatment with LOO for three consecutive days, was carried out by the construction of a concentration-response curve with oxytocin or carbachol. The primary dysmenorrhea animal model was replicated with an injection of estradiol cypionate in female mice for three consecutive days, followed by intraperitoneal application of oxytocin.

RESULTS

LOO relaxed the rat uterus precontracted with 10^-2 IU/mL oxytocin (logEC₅₀ = 1.98 ± 0.07), 1 μM carbachol (logEC₅₀ = 1.42 ± 0.07) or 60 mM KCl (logEC₅₀ = 1.53 ± 0.05). It was also able relax uterus on spontaneous contractions (logEC₅₀ = 0.41 ± 0.05). Preincubation with glibenclamide, propranolol, phentolamine or L-NAME in contractions induced by carbachol did not alter significantly the relaxing effect of LOO. However, in the presence of 4-aminopyridine, CsCl or tetraethylammonium there was a reduction of LOO potency, whereas the blockers methylene blue, ODQ, aminophylline and heparin potentiated the LOO relaxing effect. Preincubation with LOO in a Ca²⁺ free medium at concentrations of 27 μg/mL or 81 μg/mL reduced the contraction induced by carbachol. The administration of LOO for 3 days did not alter uterus contractility. The treatment with LOO at 30 or 100 mg/kg intraperitoneally, or 100 mg/kg orally, inhibited writhing in female mice. The association of LOO at 10 mg/kg with nifedipine or mefenamic acid potentiated writhing inhibition in mice.

CONCLUSIONS

The essential oil of L. origanoides has tocolytic activity in rat isolated uterus pre-contracted with KCl, oxytocin, or carbachol. This effect is possibly related to the opening of potassium channels (K_ir, K_V, and K_Ca), cAMP increase, and diminution of intracellular Ca²⁺. This relaxant effect, probably, contributed to reduce the number of writhings in an animal model of dysmenorrhea being potentiated by nifedipine or mefenamic acid. Taken together, the results here presented indicate that this species has a pharmacological potential for the treatment of primary dysmenorrhea, supporting its use in folk medicine.

Extreme Heat and Pregnancy Outcomes: A Scoping Review of the Epidemiological Evidence

BACKGROUND

Extreme heat caused by climate change is a major public health concern, disproportionately affecting poor and racialized communities. Gestational heat exposure is a well-established teratogen in animal studies, with a growing body of literature suggesting human pregnancies are similarly at risk. Characterization of extreme heat as a pregnancy risk is problematic due to nonstandard definitions of heat waves, and variable study designs. To better focus future research in this area, we conducted a scoping review to assess the effects of extreme heat on pregnancy outcomes.

METHODS

A scoping review of epidemiological studies investigating gestational heat-exposure and published 2010 and 2020, was conducted with an emphasis on study design, gestational windows of sensitivity, adverse pregnancy outcomes and characterization of environmental temperatures.

RESULTS

A sample of 84 studies was identified, predominantly set in high-income countries. Preterm birth, birthweight, congenital anomalies and stillbirth were the most common pregnancy outcome variables. Studies reported race/ethnicity and/or socioeconomic variables, however these were not always emphasized in the analysis.

CONCLUSION

Use of precise temperature data by most studies avoided pitfalls of imprecise, regional definitions of heat waves, however inconsistent study design, and exposure windows are a significant challenge to systematic evaluation of this literature. Despite the high risk of extreme heat events and limited mitigation strategies in the global south, there is a significant gap in the epidemiological literature from these regions. Greater consistency in study design and exposure windows would enhance the rigor of this field.

Role of epigenetics in parturition and preterm birth

Preterm birth occurs worldwide and is associated with high morbidity, mortality, and economic cost. Although several risk factors associated with parturition and preterm birth have been identified, mechanisms underlying this syndrome remain unclear, thereby limiting the implementation of interventions for prevention and management. Known triggers of preterm birth include conditions related to inflammatory and immunological pathways, as well as genetics and maternal history. Importantly, epigenetics, which is the study of heritable phenotypic changes that occur without alterations in the DNA sequence, may play a role in linking social and environmental risk factors for preterm birth. Epigenetic approaches to the study of preterm birth, including analyses of the effects of microRNAs, long non-coding RNAs, DNA methylation, and histone modification, have contributed to an improved understanding of the molecular bases of both term and preterm birth. Additionally, epigenetic modifications have been linked to factors already associated with preterm birth, including obesity and smoking. The prevention and management of preterm birth remains a challenge worldwide. Although epigenetic analysis provides valuable insights into the causes and risk factors associated with this syndrome, further studies are necessary to determine whether epigenetic approaches can be used routinely for the diagnosis, prevention, and management of preterm birth.

A cohort study of dysmenorrhea and risk of low birth weight

OBJECTIVE

Little is known about the association between maternal history of dysmenorrhea and perinatal outcomes. The aim of this study was to investigate the association between maternal history of dysmenorrhea and low birth weight (LBW).

METHODS

A total of 6754 pregnant women were recruited from the ongoing prospective cohort study in Guangxi, China, in 2015-2018. Information on the maternal history of dysmenorrhea was obtained by questionnaires including visual analog scale (VAS) questions during the first antenatal care visit. The association of maternal history of dysmenorrhea and LBW was evaluated using logistic regression analyses adjusted for confounding factors (infant sex, maternal age, parity, pre-pregnancy body mass index (BMI) (kg/m²), gestational age, alcohol use during pregnancy, passive smoking, and occupational status).

RESULTS

Mothers with a history of dysmenorrhea were more likely to give birth to LBW infants (adjusted odds ratio (OR)=1.44; 95% confidence interval (CI): 1.12, 1.83). Among women with a history of dysmenorrhea, women ≥29 years old (adjusted OR 1.46; 95% CI 1.02, 2.10), multiparous (adjusted OR 1.59, 95% CI 1.12, 2.25), and women gave birth to female infant (adjusted OR = 1.53, 95% CI = 1.11, 2.11) had a higher risk of LBW.

CONCLUSIONS

As the first cohort study to investigate the association between maternal history of dysmenorrhea and LBW, our study shows that dysmenorrhea may increase the risk of LBW.

Inflammatory Markers in Dysmenorrhea and Therapeutic Options

Dysmenorrhea often significantly reduces the quality of women's life and is still an important public health problem. Despite numerous studies, the pathomechanism of dysmenorrhea is not fully understood. Previous research indicates the complexity of biochemical reactions between the endocrine, vascular, and immune systems. Prostaglandins play a major role in the pathomechanism of dysmenorrhea. In contrast, cytokines and other proinflammatory factors in primary dysmenorrhea are less studied. In addition to the applied pharmacotherapy, more and more studies proving the effectiveness of non-pharmacological methods appear. Therefore, the present work contains a review of the latest research concerning factors involved in dysmenorrhea, as well as therapeutic options. In the literature search, authors used online databases, PubMed, and clinitrials.gov and browsed through individual gynecology, physiotherapy journals and books.

Effect of Chinese herbal medicine on primary dysmenorrhea: A protocol for a systematic review and meta-analysis

BACKGROUND

Primary dysmenorrhea (PD), the most common gynecological diseases, seriously affects women's life and work; however, without more effective treatment. Chinese herbal medicine (CHM) has been widely used for relieving dysmenorrheic pain in patients with PD. To assess the effectiveness and safety of CHM in patients with PD, a systematic review and meta-analysis of current published evidence regarding CHM as treatment for PD would be conducted in this study.

METHODS

Literatures related to CHM for PD from the establishment of the database to June 2019 will be retrieved from the following databases: MEDLINE, EMBACE, Wed of Science and Cochrane Central Register of Controlled Trials, Chinese Biomedical Literature Database, Chinese National Knowledge Infrastructure, and Wanfang Database. There are no language restrictions for retrieving literature. Eligible randomized clinical trials (RCTs) evaluating the effectiveness and safety of CHM in PD patients will be put in the study including outcomes of pain intensity, clinical effectiveness rate, quality of life, and adverse events. By scanning the titles, abstracts and full texts, 2 reviewers will independently select studies, extract data, and assess the quality of study. Meta-analysis of RCTs will be conducted using Review Manager 5.1 software. The results will be presented as risk ratio for dichotomous data, and standardized or weighted mean difference for continuous data.

RESULT

This study will provide high-quality available evidence for the treatment of PD with CHM based on pain, clinical efficacy, quality of life, and adverse events.

CONCLUSION

The systematic review willto evaluate the efficacy of CHM in treating PD and provide evidence for clinicians.

PROSPERO REGISTRATION NUMBER

CRD42019121185.

The Effect of Atosiban on Patients With Difficult Embryo Transfers Undergoing In Vitro Fertilization-Embryo Transfer

The purpose of this study was to evaluate the effect of atosiban on the outcomes of infertile women undergoing in vitro fertilization (IVF) with difficult embryo transfers (ETs). This randomized double-blind study enrolled 204 infertile women with difficult ETs during IVF treatment between June 2014 and June 2018. According to a computer-generated randomization list, participants were randomized into placebo (n = 102) and atosiban (n = 102) groups. In atosiban group, atosiban with a total dose of 37.5 mg was administered. All of the patients underwent IVF-ET using cryopreserved embryos. The clinical pregnancy rate per cycle and implantation rate per transfer (45.1% and 26.5%) in atosiban group were significantly higher than those of placebo group (15.6% and 9.7%, respectively; P < .05). This study showed that administration of atosiban during ET was extraordinarily effective for patients with difficult transfers.

Nonsteroidal antiinflammatory drug resistance in dysmenorrhea: epidemiology, causes, and treatment

Although nonsteroidal antiinflammatory drugs can alleviate menstrual pain, about 18% of women with dysmenorrhea are unresponsive, leaving them and their physicians to pursue less well-studied strategies. The goal of this review is to provide a background for treating menstrual pain when first-line options fail. Research on menstrual pain and failure of similar drugs in the antiplatelet category suggested potential mechanisms underlying nonsteroidal antiinflammatory drug resistance. Based on these mechanisms, alternative options may be helpful for refractory cases. This review also identifies key pathways in need of further study to optimize menstrual pain treatment.

Longitudinal analysis of DNA methylation associated with birth weight and gestational age

Gestational age (GA) and birth weight have been implicated in the determination of long-term health. It has been hypothesized that changes in DNA methylation may mediate these long-term effects. We obtained DNA methylation profiles from cord blood and peripheral blood at ages 7 and 17 in the same children from the Avon Longitudinal Study of Parents and Children. Repeated-measures data were used to investigate changes in birth-related methylation during childhood and adolescence. Ten developmental phenotypes (e.g. height) were analysed to identify possible mediation of health effects by DNA methylation. In cord blood, methylation at 224 CpG sites was found to be associated with GA and 23 CpG sites with birth weight. Methylation changed in the majority of these sites over time, but neither birth characteristic was strongly associated with methylation at age 7 or 17 (using a conservative correction for multiple testing of P < 1.03 × 10(-7)), suggesting resolution of differential methylation by early childhood. Associations were observed between birth weight-associated CpG sites and phenotypic characteristics in childhood. One strong association involved birth weight, methylation of a CpG site proximal to the NFIX locus and bone mineral density at age 17. Analysis of serial methylation from birth to adolescence provided evidence for a lack of persistence of methylation differences beyond early childhood. Sites associated with birth weight were linked to developmental genes and have methylation levels which are associated with developmental phenotypes. Replication and interrogation of causal relationships are needed to substantiate whether methylation differences at birth influence the association between birth weight and development.

Plasma metabolic profiling of normal and dysmenorrhea syndrome rats and the effects of Xiang-Fu-Si-Wu Decoction intervention

CONTEXT

Primary dysmenorrhea (PDM), a common, clinically heterogeneous endocrine disorder affecting young women, is associated with endocrinopathy and metabolic abnormalities. The Xiang-Fu-Si-Wu Decoction (XFSWD) is a traditional Chinese medicine preparation used to treat PDM.

OBJECTIVE

In the current study, a plasma metabonomics method based on the ultra-high-performance liquid chromatography-quantitative time-of-flight-mass spectrometry (UHPLC-Q-TOF-MS) system was employed to examine the mechanism of XFSWD action in PDM.

MATERIALS AND METHODS

Estradiol benzoate (0.01 g/kg/d) and oxytocin (5 mL/kg) were used to create the dysmenorrhea rat model. Based on the chromatographic data of plasma samples at different time-points following oral administration of XFSWD mixed in water (37.8 g crude herbs/kg) on day 7, partial least square (PLS) and discriminate analysis (DA) were applied to visualize group differentiation and marker selection.

RESULTS

Systemic changes occurring in PDM reflect alterations in not only uterus function but also whole-body metabolism. The XFSWD was effective as a therapeutic agent for PDM by reflect metabolic pathway. Prostaglandins and lysophospholipids were identified as two marker types for oxytocin-induced dysmenorrhea syndrome, including LysoPC(18:4), LysoPE(22:2/0:0), LysoPC(17:0), PGJ₂, 11-deoxy-11-methylene-PGD₂, 15-deoxy-δ-12,14-PGJ₂, LysoPC(20:3), etc. Specifically, the concentrations of prostaglandins compounds (PGJ₂, 11-deoxy-11-methylene-PGD₂, 15-deoxy-δ-12,14-PGJ₂) were increased while those of lysophospholipid compounds [lysoPC(18:4), LysoPE(22:2/0:0), LysoPC(17:0)] were decreased to a significant extent (p < 0.05) in dysmenorrheal rats. Upon treatment with the XFSWD at 12 h, the concentrations of lysophospholipids showed no significant differences (P > 0.05) between the model and normal groups. The lysophospholipid levels were restored. Lysophospholipids were the key factors in phospholipid metabolism. Thus, disruption of phospholipids metabolism appears critical for the development of dysmenorrhea. The XFSWD exerted its effects by interfering with the sphingolipid metabolic pathway.

DISCUSSION AND CONCLUSIONS

The metabonomics method presents a promising tool to treat PDM in animal models, and may be applicable for clinical treatment of the human disease in the future.

Altered cytokine gene expression in peripheral blood monocytes across the menstrual cycle in primary dysmenorrhea: a case-control study

Primary dysmenorrhea is one of the most common gynecological complaints in young women, but potential peripheral immunologic features underlying this condition remain undefined. In this paper, we compared 84 common cytokine gene expression profiles of peripheral blood mononuclear cells (PBMCs) from six primary dysmenorrheic young women and three unaffected controls on the seventh day before (secretory phase), and the first (menstrual phase) and the fifth (regenerative phase) days of menstruation, using a real-time PCR array assay combined with pattern recognition and gene function annotation methods. Comparisons between dysmenorrhea and normal control groups identified 11 (nine increased and two decreased), 14 (five increased and nine decreased), and 15 (seven increased and eight decreased) genes with ≥2-fold difference in expression (P<0.05) in the three phases of menstruation, respectively. In the menstrual phase, genes encoding pro-inflammatory cytokines (IL1B, TNF, IL6, and IL8) were up-regulated, and genes encoding TGF-β superfamily members (BMP4, BMP6, GDF5, GDF11, LEFTY2, NODAL, and MSTN) were down-regulated. Functional annotation revealed an excessive inflammatory response and insufficient TGF-β superfamily member signals with anti-inflammatory consequences, which may directly contribute to menstrual pain. In the secretory and regenerative phases, increased expression of pro-inflammatory cytokines and decreased expression of growth factors were also observed. These factors may be involved in the regulation of decidualization, endometrium breakdown and repair, and indirectly exacerbate primary dysmenorrhea. This first study of cytokine gene expression profiles in PBMCs from young primary dysmenorrheic women demonstrates a shift in the balance between expression patterns of pro-inflammatory cytokines and TGF-β superfamily members across the whole menstrual cycle, underlying the peripheral immunologic features of primary dysmenorrhea.

Vasopressin V1a and V1b Receptors: From Molecules to Physiological Systems

The neurohypophysial hormone arginine vasopressin (AVP) is essential for a wide range of physiological functions, including water reabsorption, cardiovascular homeostasis, hormone secretion, and social behavior. These and other actions of AVP are mediated by at least three distinct receptor subtypes: V1a, V1b, and V2. Although the antidiuretic action of AVP and V2 receptor in renal distal tubules and collecting ducts is relatively well understood, recent years have seen an increasing understanding of the physiological roles of V1a and V1b receptors. The V1a receptor is originally found in the vascular smooth muscle and the V1b receptor in the anterior pituitary. Deletion of V1a or V1b receptor genes in mice revealed that the contributions of these receptors extend far beyond cardiovascular or hormone-secreting functions. Together with extensively developed pharmacological tools, genetically altered rodent models have advanced the understanding of a variety of AVP systems. Our report reviews the findings in this important field by covering a wide range of research, from the molecular physiology of V1a and V1b receptors to studies on whole animals, including gene knockout/knockdown studies.

Neonatal DNA methylation patterns associate with gestational age

Risk for adverse neonatal outcome increases with declining gestational age (GA), and changes in DNA methylation may contribute to the relationship between GA and adverse health outcomes in offspring. To test this hypothesis, we evaluated the association between GA and more than 27,000 CpG sites in neonatal DNA extracted from umbilical cord blood from two prospectively-characterized cohorts: (1) a discovery cohort consisting of 259 neonates from women with a history of neuropsychiatric disorders and (2) a replication cohort consisting of 194 neonates of uncomplicated mothers. GA was determined by obstetrician report and maternal last menstrual period. The associations between proportion of DNA methylated and GA were evaluated by fitting a separate linear mixed effects model for each CpG site, adjusting for relevant covariates including neonatal sex, race, parity, birth weight percentile and chip effects. CpG sites in 39 genes were associated with GA (false discovery rate < 0.05) in the discovery cohort. The same CpG sites in 25 of these genes replicated in the replication cohort, with each association replicating in the same direction. Notably, these CpG sites were located in genes previously implicated in labor and delivery (e.g., AVP, OXT, CRHBP and ESR1) or that may influence the risk for adverse health outcomes later in life (e.g., DUOX2, TMEM176A and CASP8). All associations were independent of method of delivery or induction of labor. These results suggest neonatal DNA methylation varies with GA even in term deliveries. The potential contribution of these changes to clinically significant postnatal outcomes warrants further investigation.

A narrative review of medical, chiropractic, and alternative health practices in the treatment of primary dysmenorrhea

OBJECTIVE

Primary dysmenorrhea and related issues are discussed as they influence the gynecological and social health of females during adolescence, adulthood, and senior maturity. Health practitioners are exposed to multiple approaches towards the management of menstrual pain. Clinical and social viewpoints target the causation, development, diagnosis, manifestation and management of primary dysmenorrhea. This narrative review includes the topic of the doctor-patient relationship in efforts of cultivating effectively communicative health practitioners. Controversial topics related to primary dysmenorrhea and the quality of life for women are addressed.

DATA SOURCES

A search for literature reviews, case studies, laboratory research, and clinical trials from 1985-2004 was performed using the MEDLINE database. Sources of additional information included textbooks, national organizational literature and contemporary articles.

DISCUSSION

Menstrual pain is a prevalent experience yet it is socially taboo for conversation; as such, it poses a hindrance to its management. The communication between the doctor and patient is a critical barrier point between establishing a diagnosis and determining an appropriate treatment plan. A multi-disciple treatment plan varies as much as patients themselves vary in personal experiences, needs, and preferences.

CONCLUSIONS

Medicinal prophylactics, physical therapeutics, non-acidic diets, herbal supplements, eastern therapies and the chiropractic manual adjustments of the spine are effective methods for the management of primary dysmenorrhea. The non-invasive management of primary dysmenorrhea includes the chiropractic adjustment with complimentary modalities, and other alternative health care practices. Medicinal prophylactics are invasive and pose a higher risk to long-term chemical exposure, side effects or irreversible conditions.

A double-blind, randomised, crossover study of two doses of a single-tablet combination of ibuprofen/paracetamol and placebo for primary dysmenorrhoea

OBJECTIVES

Efficacy of pain relief may potentially be enhanced by combining two or more analgesics with different mechanisms of action. The objective of this study was to assess the efficacy and tolerability of a novel single-tablet combination of ibuprofen and paracetamol compared with placebo in females experiencing moderate-to-severe pain due to primary dysmenorrhoea, a prevalent, recurrent condition characterised by pain at the time of menses.

METHODS

This was a phase II/III, double-blind, randomised, cross-over, single-dose study in 94 women with moderate-to-severe dysmenorrhoea, examining the efficacy and tolerability of one or two tablets of a single-tablet combination of ibuprofen 200 mg/paracetamol 500 mg compared with placebo.

CLINICAL TRIAL REGISTRATION

ISRCTN42521357

RESULTS

Total pain relief over 6 hours post-dose (TOTPAR(0-6h)) was significantly greater following administration of two tablets of the single-tablet combination of ibuprofen 200 mg/paracetamol 500 mg compared with placebo (LS means: 2.35, 1.85, respectively; p = 0.0001) and approached significance for one tablet (LS mean: 2.10; p = 0.054). Statistically superior pain relief and reductions in pain intensity were achieved from 2 hours and 90 minutes post-dose, respectively, with the higher dose combination, and from 4 hours with the lower dose combination compared with placebo. Overall effectiveness (sum of pain intensity difference and pain relief score [SPRID] over 6 hours) were statistically superior to placebo for both one and two tablets of the ibuprofen/paracetamol combination (p = 0.0011 and p = 0.03, respectively). Both dose combinations were well-tolerated. Adverse events were minor and their frequency and nature did not differ with either treatment compared with placebo.

CONCLUSIONS

One or two tablets of a single-tablet combination of ibuprofen 200 mg/paracetamol 500 mg is well-tolerated and provides superior analgesic efficacy to placebo in patients with primary dysmenorrhoea.

Oxytocin antagonists may improve infertility treatment

OBJECTIVE

To confirm the improvement of uterine receptivity following administration of oxytocin and vasopressin V1A antagonist atosiban.

DESIGN

Case report.

SETTING

Private reproductive medicine center.

PATIENT(S)

A 42-year-old woman with a history of 15 years' infertility and seven failed in vitro fertilization/embryo transfer (IVF-ET) attempts.

INTERVENTION(S)

Atosiban (mixed vasopressin V1A/oxytocin antagonist registered for the treatment of imminent premature birth) was administered on the 14th day of endometrial synchronization for oocyte donation.

MAIN OUTCOME MEASURE(S)

Uterine contractile activity (component of uterine receptivity) and success of treatment of infertility.

RESULT(S)

Intense spontaneous uterine contractility was visualized by transvaginal sonography. After 1 hour of intravenous infusion of atosiban, a repeated scan showed a significant decrease in contractile activity (11 vs 7 contractions per 4 minutes, respectively). The ET was performed immediately after, and the infusion of atosiban continued for the next 2 hours. The treatment decreased the uterine contractile activity and resulted in successful embryo implantation and a normal twin diamniotic pregnancy.

CONCLUSION(S)

Atosiban may improve uterine receptivity during ET and may increase success rates of advanced infertility treatment procedures.

Physiology of Upward Transport in the Human Female Genital Tract

The uterus and fallopian tubes represent a functionally united peristaltic pump under the endocrine control of ipsilateral ovary. We have examined this function by using hysterosalpingoscintigraphy (HSS), recording of intrauterine pressure, electrohysterography, and Doppler sonography of the fallopian tubes. An uptake of labeled particles into the uterus was observed during the follicular and luteal phases of the cycle after application into the vagina. Transport into the oviducts, however, could only be demonstrated during the follicular phase. Furthermore, the predominant transport was into the tube ipsilateral to the ovary containing the dominant follicle. The pregnancy rate following spontaneous intercourse or insemination was higher in those women in whom ipsilateral transport could be demonstrated. The amount of material transported to the ipsilateral tube was increased after oxytocin administration, as demonstrated by radionuclide imaging and by Doppler sonography following instillation of ultrasound contrast medium. An increase in the basal tone and amplitude of contractions was observed after oxytocin administration. These results support the idea that the uterus and fallopian tubes act as a peristaltic pump, which increases transport of sperm into the oviduct ipsilateral to the ovary bearing the dominant follicle. Oxytocin appears to play a critical role in this peristaltic pump. A failure of the peristaltic mechanism is possibly responsible for infertility. We propose the term tubal transport disorder (TTD) as a nosological entity. Results from HSS could be a useful adjunct for choosing treatment modalities in patients with patent fallopian tubes suffering from infertility. These patients may be better served with in vitro fertilization (IVF).

Effect of atosiban on rabbit embryo development and human sperm motility

OBJECTIVE

To investigate embryotoxic potential and effects on human sperm motility of the mixed vasopressin V(1a)/oxytocin receptor antagonist atosiban considered for novel indication of improvement of uterine receptivity in embryo-transfer recipients.

DESIGN

One-cell rabbit embryo bioassay and human sperm motility bioassay were performed in control media or in media containing atosiban.

SETTING

Private center of reproductive medicine and academic research institute of reproduction biotechnology.

ANIMAL(S)

Rabbit females (New Zealand and California, N = 15) aged 4.5-6.5 months.

INTERVENTION(S)

In vitro exposure of one-cell rabbit embryos and human sperm to atosiban in the range of therapeutic concentrations clinically occurring in human beings.

MAIN OUTCOME MEASURE(S)

Embryo development and sperm motility.

RESULT(S)

Preimplantation development of one-cell rabbit embryos was not affected by atosiban in the concentrations < or =15,000 nM, which was 50-fold higher than the mean plasma concentration reached during regular therapy (300 nM). Atosiban did not affect human sperm motility in concentrations of < or =3,000 nM, in other words, 10 times the human mean plasma concentration.

CONCLUSION(S)

Clinical application of atosiban in the proposed indication may be safe for embryos because it is compatible with preimplantation rabbit embryo development and human sperm motility.

Effect of short-term, low-dose treatment with tamoxifen in patients with primary dysmenorrhea

Current treatment of painful periods and other symptoms related to primary dysmenorrhea (PD) is usually commenced with non-steroidal anti-inflammatory drugs or oral contraceptives, which fails in about 10% of affected patients. Tamoxifen, a selective estrogen-receptor modulator (SERM), has been demonstrated to directly inhibit uterine contractions, causing improvement in uterine blood flow. It could be considered for application in selected groups of dysmenorrheic patients, for instance carriers of breast cancer-associated antigen (BRCA) genes, breast cancer survivors or women with advanced endometriosis. Thus the aim of the present study was to investigate the effect of short-term treatment with tamoxifen on PD and PD-related symptoms, as well as its direct effect on parameters of intrauterine pressure during the painful menstruation, in a group of dysmenorrheic patients. After two cycles of administration of tamoxifen we noted a significant decrease in bleeding together with reductions in the severity of menstrual cramps, diarrhea, headache, fatigue and anxiety. In intrauterine pressure assessments, tamoxifen significantly decreased propagation of uterine contractions. In conclusion, SERMs such as tamoxifen may constitute a therapeutic option in selected groups of patients, improving dysmenorrheic symptoms. Additionally to its receptor-mediated effects, tamoxifen was shown to exert a direct influence on uterine contractile activity that may explain the decrease of menstrual pain and cramps noted in the studied group.

Contractile reactivity of human myometrium in isolated non-pregnant uteri

BACKGROUND

Perfusion of the isolated uterus has been shown to be a feasible experimental system for studies of the human endometrium and myometrium. Utilizing our established experimental perfusion model we perfused 20 uteri for 27 h and investigated the contractile reactivity of the myometrium in response to 17beta-estradiol (E2) and oxytocin (OT).

METHODS

Uteri of group A (n = 4) were stimulated with OT; group B (n = 4) was treated continuously with E2; group C (n = 4) received both E2 and OT for 27 h; group D (n = 4) was perfused for 27 h with E2 with the addition of OT for the last 3 h of the experiment; group E (n = 4) as control group remained without any treatment. The pressure and duration of uterine contractions were recorded during the entire perfusion period using intramural and endoluminal pressure catheters.

RESULTS

Compared to the other treatment groups and controls, the most effective myometrial activity was achieved in group D during the OT stimulation period. No relevant myometrial activity was detected in the control group.

CONCLUSIONS

Continuous E2 treatment, with the addition of OT for the last 3 h of the 27 h perfusion period, led to the most pronounced uterotonic effects in the presented experimental condition.

Inhibitory effect of barusiban and atosiban on oxytocin-induced contractions of myometrium from preterm and term pregnant women

BACKGROUND

A synthetic oxytocin analogue, barusiban, was shown to potently inhibit oxytocin-induced activity of myometrium from term pregnant women. The responsiveness to vasopressin was not influenced by the compound.

OBJECTIVE

To test the effect of barusiban and a reference compound, atosiban, on oxytocin-induced activity of myometrium from women at preterm pregnancy in comparison to myometrium from women at term.

METHODS

Fifteen preterm (30-36 gestational weeks) and 12 term pregnant women (38-41 weeks) who underwent cesarean delivery donated myometrial tissue for the study. Concentration-response curves following oxytocin administration to isolated myometrial strips were recorded in control experiments, in the presence of barusiban at concentrations of 2.5, 25, and 250 nM, and of atosiban at concentrations of 25, 250, and 750 nM. Effective concentration 50% (EC50) and pA2 values were calculated.

RESULTS

Both antagonists in higher concentrations increased the EC50 values to oxytocin. The median pA2 value for preterm myometrium with barusiban was 9.76 and with atosiban 7.86. For term myometrium the corresponding pA2 results were 9.89 and 7.81, respectively. None of these pA2 values differed to any statistically significant degree.

CONCLUSION

The selective oxytocin antagonist, barusiban, concentration-dependently inhibits oxytocin-induced myometrial contractions of both preterm and term myometrium at least as potently as atosiban. It remains to be determined if the selectivity of barusiban for the oxytocin receptor confers an advantage over atosiban as a tocolytic in preterm labor.

Tocolysis with atosiban: experience in the management of premature labor before 24 weeks of pregnancy

OBJECTIVE

Atosiban has been shown to be an effective tocolytic agent with a low rate of side effects during 24 to 33 weeks of gestation. Atosiban acts through selective, competitive inhibition of both oxytocin and vasopressin, so that there are reasons to assume that a tocolytic effect can also be achieved earlier in the pregnancy.

STUDY DESIGN

In this prospective, randomized pilot study, 20 women in the 18th through 24th week of gestation who presented at our hospital with preterm labor were treated with atosiban. In the control group 20 women received saline infusions. All patients received antibiotic therapy. A cervical cerclage was performed when indicated as was correction of the vaginal pH.

RESULTS

The tocolytic effect began after 3-10 min (median: 6.5 min). Treatment time until the complete absence of contractions was 3-12 h (median: 7.5 h). Pregnancies were prolonged between 11.1 and 21.7 weeks (median: 15.6 weeks) in the atosiban group vs. 10.5-19.1 weeks in the control group. If well tolerated, atosiban was continued. There were no significant alterations in the routine laboratory parameters, circulation parameters, and fluid balance.

CONCLUSION

In summary, atosiban showed itself to be effective for tocolytic treatment for premature labor, even during 18 and 24 weeks of pregnancy, while exhibiting its known, favorable profile of side effects.

SSR126768A (4-chloro-3-[(3R)-(+)-5-chloro-1-(2,4-dimethoxybenzyl)-3-methyl-2-oxo-2,3-dihydro-1H-indol-3-yl]-N-ethyl-N-(3-pyridylmethyl)-benzamide, hydrochloride): a new selective and orally active oxytocin receptor antagonist for the prevention of preterm labor

4-chloro-3-[(3R)-(+)-5-chloro-1-(2,4-dimethoxybenzyl)-3-methyl-2-oxo-2,3-dihydro-1H-indol-3-yl]-N-ethyl-N-(3-pyridylmethyl)benzamide, hydrochloride (SSR126768A), a new potent and selective, orally active oxytocin (OT) receptor antagonist was characterized in several biochemical and pharmacological models. In binding studies, SSR126768A showed nanomolar affinity for rat and human recombinant and native OT receptors (K(i) = 0.44 nM) and exhibited much lower affinity for V(1a), V(1b), and V(2) receptors. In addition, it did not interact with a large number of other receptors, enzymes, and ion channels (1 microM). In autoradiographic experiments performed on at-term human pregnant uterus sections, SSR126768A dose dependently displaced [I(125)]d(CH(2))(5)[Tyr(Me)(2), Thr(4), Orn(8) (125)I-Tyr-NH(2)(9)]VT in situ labeling to OT receptors highly expressed in these tissues. In functional studies, SSR126768A behaved as a full antagonist and potently antagonized OT-induced intracellular Ca(2+) increase (K(i) = 0.50 nM) and prostaglandin release (K(i) = 0.45 nM) in human uterine smooth muscle cells. In rat isolated myometrium, OT-induced uterine contractions were competitively antagonized by SSR126768A (pA(2) = 8.47). Similarly, in human pregnant myometrial strips, SSR126768A inhibited the contractile uterine response to OT. In conscious telemetrated rats, oral administration of SSR126768A (1-10 mg/kg) produced a competitive inhibition of the dose response to OT on uterine contractions up to 24 h at 3 mg/kg p.o.; no tachyphylaxis was observed after 4-day repeated treatment. Finally, SSR126768A (30 mg/kg p.o.) significantly delayed parturition in pregnant rats in labor similar to ritodrine (10 mg/kg p.o.). Thus, SSR126768A is a potent, highly selective, orally active OT receptor antagonist with a long duration of action. This molecule could find therapeutic application as a tocolytic agent for acute and chronic oral management of preterm labor.