Pharmacology of oxytocin and prostaglandins

Sublingual Misoprostol-Induced Rhabdomyolysis and Convulsions in Postpartum Hemorrhage: A Case Report and Literature Review

Postpartum hemorrhage (PPH) remains the leading cause of maternal mortality, primarily attributed to uterine atony. Both the World Health Organization (WHO) and the International Federation of Gynecology and Obstetrics (FIGO) endorse the use of misoprostol not only for the prevention but also for the treatment of PPH. However, the administration of misoprostol is commonly associated with transient pyrexia, attributed to a shift in the hypothalamic set point observed in certain animal studies. Misoprostol-induced hyperpyrexia can occasionally manifest with a prodrome of shivering, particularly when administered via the sublingual route, which achieves a higher and faster maximum plasma concentration compared to vaginal and rectal routes. General management strategies to reduce fever involve removing clothing and blankets, applying cool compresses, administering oral acetaminophen, and ensuring adequate hydration. While some cases have reported misoprostol-induced convulsions, hyperpyrexia leading to convulsions and subsequent rhabdomyolysis is a rare and potentially lethal side effect. In this case presentation, we emphasize a scenario where misoprostol was employed for the treatment of PPH but led to rhabdomyolysis. Our goal is to highlight the side effects of misoprostol and the significance of considering the initial combination of misoprostol with anti-pyretic management to minimize the risk of hyperthermia-related side effects and prevent additional severe complications.

Oxytocin and vaginal dinoprostone in labor induction: A systematic review and meta-analysis

BACKGROUND

The comparison between prostaglandin E2 (PGE2) and oxytocin and for induction of labor (IOL) remains controversial.

OBJECTIVE

The present study aimed to determine the safety and efficacy of these two agents in IOL.

SEARCH STRATEGY

PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov. from the establishment of the database to April 23, 2023.

SELECTION CRITERIA

A search was conducted with keywords "labor, induction, prostaglandin E2/PGE2/dinoprostone, and oxytocin". Only randomized clinical trials comparing oxytocin and vaginal dinoprostone in women who were at least late preterm (gestational age [GA] ≥34 weeks), singleton pregnant, and had intact membranes were enrolled for further meta-analysis.

DATA COLLECTION AND ANALYSIS

We conducted both a descriptive analysis and a meta-analysis. In the meta-analysis, we utilized the Mantel-Haenszel random effects model to analyze dichotomous data, employing the relative risk (RR) as the effect measure along with 95% confidence intervals (CIs). The study quality was evaluated using Cochrane Collaboration's risk of bias assessment tool (RoB 2). A random-effects model was applied for the meta-analysis.

MAIN RESULTS

After screening 3303 articles from five databases, a total of nine randomized controlled studies composed of 1071 patients were included. Our analysis included 534 patients in the PGE2 group and 537 patients in the oxytocin group. The pooled estimate of vaginal deliveries following PGE2 induction stood at 84.2%, while after oxytocin induction, it was 79.8%. The meta-analysis showed no statistical difference between the two groups in terms of the rate of vaginal delivery (pooled RR, 1.05; 95% CI: 0.95-1.16; P value for Q, 0.001; I2 , 71.14%), cesarean section (pooled RR, 0.84; 95% CI: 0.52-1.35; P value for Q, 0.007; I2 , 61.69%) and induction-delivery interval (pooled standard mean difference, 0.09; 95% CI: -0.67 to 0.85; P value for Q, 0.000; I2 , 96.45%). Since the results for fetal distress and uterine hyperstimulation were consistent across all enrolled studies, no further meta-analysis was conducted.

CONCLUSIONS

When amalgamating the available literature, it implies that oxytocin was found to have similar effects as PGE2 on delivery outcomes and safety concerns in pregnant women with GA ≥36 weeks. Although the uterine cervix was unfavorable, both low and high doses of oxytocin were feasible for IOL.

From love to pain: is oxytocin the key to grief complications?

While most adults confronted with the death of a loved one manage to grieve, about 10-20% of individuals develop complicated grief, characterized by persistent distress and impaired social skills, or pathological grief, defined by the onset or decompensation of a psychiatric disorder. Little is known about the biological causes of these grief complications. Recent work suggests that oxytocin, a major neuroendocrine hormone regulating many neurocognitive mechanisms, may be involved in this process. Oxytocin is widely studied and well known for its impact on the mother-child bond and hormonal and brain systems related to attachment and social interactions. In this article, we propose a neurocognitive model of grief complications based on existing data on the role of oxytocin in interpersonal attachment and its impact on brain activity. We suggest that complicated grief is associated with dysfunctional cerebral oxytocinergic signaling and persistent hyperactivation of the nucleus accumbens. This mechanism is involved in limiting the reduction of interpersonal attachment to the deceased during acute phases and in searching for new interpersonal relationships during the recovery phase. We show how the exploration of cerebral oxytocinergic signaling would improve the understanding of physiological grief mechanisms in the general population and could allow the development of new therapeutic perspectives against the complications of grief.

Maternal and newborn plasma oxytocin levels in response to maternal synthetic oxytocin administration during labour, birth and postpartum - a systematic review with implications for the function of the oxytocinergic system

BACKGROUND

The reproductive hormone oxytocin facilitates labour, birth and postpartum adaptations for women and newborns. Synthetic oxytocin is commonly given to induce or augment labour and to decrease postpartum bleeding.

AIM

To systematically review studies measuring plasma oxytocin levels in women and newborns following maternal administration of synthetic oxytocin during labour, birth and/or postpartum and to consider possible impacts on endogenous oxytocin and related systems.

METHODS

Systematic searches of PubMed, CINAHL, PsycInfo and Scopus databases followed PRISMA guidelines, including all peer-reviewed studies in languages understood by the authors. Thirty-five publications met inclusion criteria, including 1373 women and 148 newborns. Studies varied substantially in design and methodology, so classical meta-analysis was not possible. Therefore, results were categorized, analysed and summarised in text and tables.

RESULTS

Infusions of synthetic oxytocin increased maternal plasma oxytocin levels dose-dependently; doubling the infusion rate approximately doubled oxytocin levels. Infusions below 10 milliunits per minute (mU/min) did not raise maternal oxytocin above the range observed in physiological labour. At high intrapartum infusion rates (up to 32 mU/min) maternal plasma oxytocin reached 2-3 times physiological levels. Postpartum synthetic oxytocin regimens used comparatively higher doses with shorter duration compared to labour, giving greater but transient maternal oxytocin elevations. Total postpartum dose was comparable to total intrapartum dose following vaginal birth, but post-caesarean dosages were higher. Newborn oxytocin levels were higher in the umbilical artery vs. umbilical vein, and both were higher than maternal plasma levels, implying substantial fetal oxytocin production in labour. Newborn oxytocin levels were not further elevated following maternal intrapartum synthetic oxytocin, suggesting that synthetic oxytocin at clinical doses does not cross from mother to fetus.

CONCLUSIONS

Synthetic oxytocin infusion during labour increased maternal plasma oxytocin levels 2-3-fold at the highest doses and was not associated with neonatal plasma oxytocin elevations. Therefore, direct effects from synthetic oxytocin transfer to maternal brain or fetus are unlikely. However, infusions of synthetic oxytocin in labour change uterine contraction patterns. This may influence uterine blood flow and maternal autonomic nervous system activity, potentially harming the fetus and increasing maternal pain and stress.

Effects of the Oxytocin Hormone on Pelvic Floor Muscles in Pregnant Rats

Background and Objectives: Oxytocin induction is a known risk factor for pelvic floor disorders (PFDs). The aim of the study was to investigate the effects of oxytocin induction on pelvic floor muscles in pregnant rats. Methods: Thirty-two female Wistar rats were included and divided into four groups (n = 8). The groups were as follows: virgin group (group I)-from which muscles were dissected at the beginning of the experiment; spontaneous vaginal delivery (group II) which has delivery spontaneously; saline control group (group III) and oxytocin group (group IV). In groups III and IV, pregnancy was induced on d 21 of pregnancy, with 2.5 mU saline solution or iv oxytocin, respectively, delivered by the intravenous (iv) route in pulses at 10-min intervals for 8 h. Then, the rats were euthanized, the m. coccygeus, m. iliocaudalis and m. pubocaudalis muscles were excised and tissue samples were taken. After histological processing, the vertical and horizontal dimensions of the muscles were analyzed under a light microscope. Results: In group IV; the measurement of the horizontal dimension of the m. pubocaudalis muscles was 50.1 ± 5.4 µm and it was significantly higher than other groups (p < 0.001). In group III; the mean value of the horizontal dimension of m. coccygeus muscle was found to be 49.5 ± 10.9 µm and it was significantly higher than other groups (p < 0.009). Between-group comparisons revealed no difference in mean m. iliocaudalis muscle dimension (p > 0.05). Conclusions: As a result of our study it can say that whether oxytocin induced or not, vaginal birth is a process that affects the pelvic muscles.

Ewe breed differences in the cervical transcriptome at the follicular phase of a synchronised oestrous cycle

Background

Cervical artificial insemination (AI) with frozen-thawed semen results in unacceptably low pregnancy rates internationally. The exception is in Norway, where vaginal deposition of frozen-thawed semen to a natural oestrous routinely yields pregnancy rates in excess of 70%. Previous studies by our group has demonstrated that this is due to differences in cervical sperm transport. However, a potentially important contributory factor is that ewes are inseminated to a natural oestrous in Norway but to a synchronised oestrous across most of the rest of the world. In this study, we interrogated the gene expression of the sheep cervix of four ewe breeds with known differences in pregnancy rates following cervical AI using frozen-thawed semen under the effect of exogenous hormones to synchronise the oestrous cycle. These four ewe breeds (n = 8 to 11 ewes per breed) are from two countries: Ireland (Belclare and Suffolk; medium and low fertility, respectively) and Norway (Norwegian White Sheep (NWS) and Fur; both with high fertility compared to the Irish ewe breeds).

Results

RNA extracted from cervical biopsies collected from these breeds was analysed by RNA-sequencing and differential gene expression analysis. Using the low-fertility Suffolk breed as a reference level; 27, 1827 and 2641 genes were differentially expressed in Belclare, Fur and NWS ewes, respectively (P <  0.05 and FC > 1.5). Gene ontology (GO) analysis revealed that Fur and NWS had an up-regulation of enriched pathways involved in muscle contraction and development compared to Suffolk. However, there was a down-regulation of the immune response pathway in NWS compared to Suffolk. In addition, GO analysis showed similar expression patterns involved in muscle contraction, extracellular matrix (ECM) development and cell-cell junction in both Norwegian ewe breeds, which differed to the Irish ewe breeds.

Conclusions

This novel study has identified a number of conserved and breed-specific biological processes under the effect of oestrous synchronisation that may impact cervical sperm transport during the follicular phase of the reproductive cycle.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08603-8.

Comparison of delivery outcomes in low-dose and high-dose oxytocin regimens for induction of labor following cervical ripening with a balloon catheter: A retrospective observational cohort study

A variety of oxytocin regimens are used for labor induction and augmentation. Considering the increasing rates of labor induction, it is important to assess the most optimal oxytocin regimen without compromising maternal and fetal safety. The aim of this study was to compare delivery outcomes of low-dose and high-dose oxytocin induction protocols. This retrospective cohort study of 487 women comparing low-dose oxytocin protocol (n = 280) and high-dose oxytocin protocol (n = 207) in labor induction following cervical ripening by balloon catheter was performed in Helsinki University Hospital after implementation of a new oxytocin induction protocol. The study included two six-month cohorts from 2016 and 2019. Women with vital singleton pregnancies ≥37 gestational weeks, cephalic presentation, and intact amniotic membranes were included. The primary outcome was the rate of vaginal delivery. The secondary outcomes were the rates of maternal and neonatal infections, postpartum hemorrhage, umbilical artery blood pH-value, admission to neonatal intensive care, and induction-to-delivery interval. Statistical analyses were performed by using IBM SPSS Statistics for Windows (Armonk, NY, USA). The rate of vaginal delivery was higher [69.9% (n = 144) vs. 47.9% (n = 134); p<0.004] and the rates of maternal and neonatal infection were lower during the new high-dose oxytocin protocol [maternal infections 13.6% (n = 28) vs. 22.1% (n = 62); p = 0.02 and neonatal infection 2.9% (n = 6) vs. 14.6% (n = 41); p<0.001, respectively]. The rates of post-partum hemorrhage, umbilical artery blood pH-value <7.05 or neonatal intensive care admissions did not differ between the cohorts. The median induction-to-delivery interval was shorter in the new protocol [32.0 h (IQR 18.5–42.7) vs. 37.9 h (IQR 27.8–52.8); p<0.001]. In conclusion, implementation of the new continuous high-dose oxytocin protocol resulted in higher rate of vaginal delivery and lower rate of maternal and neonatal infections. Our experience supports the use of high-dose continuous oxytocin induction regimen with a practice of stopping oxytocin once active labor is achieved, and a 15–18-hour maximum duration for oxytocin induction in the latent phase of labor following cervical ripening with a balloon catheter.

Oxytocin: A citation network analysis of 10 000 papers

Our understanding of the oxytocin system has been built over the last 70 years by the work of hundreds of scientists, reported in thousands of papers. Here, we construct a map to that literature, using citation network analysis in conjunction with bibliometrics. The map identifies ten major 'clusters' of papers on oxytocin that differ in their particular research focus and that densely cite papers from the same cluster. We identify highly cited papers within each cluster and in each decade, not because citations are a good indicator of quality, but as a guide to recognising what questions were of wide interest at particular times. The clusters differ in their temporal profiles and bibliometric features; here, we attempt to understand the origins of these differences.

Comparison between 200 μg and 800 μg of vaginal misoprostol for cervical ripening before operative hysteroscopy: A randomized controlled trial

OBJECTIVE

To compare between 200 and 800 μg of vaginal misoprostol for cervical ripening before operative hysteroscopy.

METHODS

Quadruple-blind randomized clinical trial conducted between November 2019 and September 2020 involving 76 patients undergoing cervical dilatation before surgical hysteroscopy at teaching hospitals in Pernambuco, Brazil. Women received the vaginal misoprostol dosage of 200 or 800 μg,10-12 h before operative hysteroscopy. The cervical width was the primary outcome, and secondary outcomes were patient satisfaction, adverse effects, surgical complications, and duration of cervical dilatation. Chi-square tests of association, Fisher's exact and Mann-Whitney U tests were used with an α error of <5%.

RESULTS

There was no statistical difference between the groups in the mean of the cervical width (800 μg: 6.5 ± 1.6 mm vs 200 μg: 5.8 ± 1.8 mm, P = 0.055), patient satisfaction, and surgical findings, but the duration of cervical dilatation was lower in the 800-μg group (28.16 ± 28.5 s vs 41.97 ± 31.0 s, P = 0.035). Among the adverse effects, diarrhea was more frequent in the 800-μg group with statistical difference (100% vs 0%; P = 0.01).

CONCLUSION

For cervical ripening, 200 μg misoprostol is equally effective with fewer adverse effects than 800 μg before operative hysteroscopy. ClinicalTrials.gov: NCT04152317. https://clinicaltrials.gov/ct2/show/NCT04152317.

Conserved and breed-specific differences in the cervical transcriptome of sheep with divergent fertility at the follicular phase of a natural oestrus cycle

BACKGROUND

The outcome of cervical artificial insemination (AI) with frozen-thawed semen in sheep is limited by the inability of sperm to traverse the cervix of some ewe breeds. Previous research has demonstrated that cervical sperm transport is dependent on ewe breed, as sperm can traverse the cervix in greater numbers in some higher fertility ewe breeds. However, the molecular mechanisms underlying ewe breed differences in sperm transport through the cervix remain unknown. In this study, we aimed to characterise the cervical transcriptome of four European ewe breeds with known differences in pregnancy rates following cervical AI using frozen-thawed semen at the follicular phase of a natural oestrous cycle. Cervical post mortem tissue samples were collected from two Irish ewe breeds (Belclare and Suffolk; medium and low fertility, respectively) and from two Norwegian ewe breeds (Norwegian White Sheep (NWS) and Fur; high fertility compared to both Irish breeds) at the follicular phase of a natural oestrous cycle (n = 8 to 10 ewes per breed).

RESULTS

High-quality RNA extracted from biopsies of the mid-region of the cervix was analysed by RNA-sequencing and Gene Ontology (GO). After stringent filtering (P <  0.05 and FC > 1.5), a total of 11, 1539 and 748 differentially expressed genes (DEGs) were identified in Belclare, Fur and NWS compared to the low fertility Suffolk breed, respectively. Gene ontology analysis identified significantly enriched biological processes involved in muscle contraction, extracellular matrix (ECM) development and the immune response. Gene co-expression analysis revealed similar patterns in muscle contraction and ECM development modules in both Norwegian ewe breeds, which differed to the Irish ewe breeds.

CONCLUSIONS

These breed-specific biological processes may account for impaired cervical sperm transport through the cervix in sheep during the follicular phase of the reproductive cycle. This novel and comprehensive dataset provides a rich foundation for future targeted initiatives to improve cervical AI in sheep.

Cervical Ripening and Labor Induction and Augmentation, 5th Edition

Cervical ripening and induction and augmentation of labor are common procedures in labor and birth units. The potential risks and benefits for the procedure should be explained to women so that they can make informed decisions. Clinicians should be knowledgeable about the methods and medications used and be skilled in maternal-fetal assessment. Adequate nurse staffing is required to monitor the mother and fetus to promote the best possible outcomes. This practice monograph includes information on mechanical and pharmacologic methods for cervical ripening; labor induction and augmentation with oxytocin, a high alert drug; and nurse staffing levels and skills needed to provide safe and effective care during cervical ripening and labor induction and augmentation.

Cervical Ripening and Labor Induction and Augmentation, 5th Edition

Cervical ripening and induction and augmentation of labor are common procedures in labor and birth units. The potential risks and benefits for the procedure should be explained to women so that they can make informed decisions. Clinicians should be knowledgeable about the methods and medications used and be skilled in maternal-fetal assessment. Adequate nurse staffing is required to monitor the mother and fetus to promote the best possible outcomes. This practice monograph includes information on mechanical and pharmacologic methods for cervical ripening; labor induction and augmentation with oxytocin, a high alert drug; and nurse staffing levels and skills needed to provide safe and effective care during cervical ripening and labor induction and augmentation.

Metabolic Effects of Oxytocin

There is growing evidence that oxytocin (OXT), a hypothalamic hormone well recognized for its effects in inducing parturition and lactation, has important metabolic effects in both sexes. The purpose of this review is to summarize the physiologic effects of OXT on metabolism and to explore its therapeutic potential for metabolic disorders. In model systems, OXT promotes weight loss by decreasing energy intake. Pair-feeding studies suggest that OXT-induced weight loss may also be partly due to increased energy expenditure and/or lipolysis. In humans, OXT appears to modulate both homeostatic and reward-driven food intake, although the observed response depends on nutrient milieu (eg, obese vs. nonobese), clinical characteristics (eg, sex), and experimental paradigm. In animal models, OXT is anabolic to muscle and bone, which is consistent with OXT-induced weight loss occurring primarily via fat loss. In some human observational studies, circulating OXT concentrations are also positively associated with lean mass and bone mineral density. The impact of exogenous OXT on human obesity is the focus of ongoing investigation. Future randomized, placebo-controlled clinical trials in humans should include rigorous, standardized, and detailed assessments of adherence, adverse effects, pharmacokinetics/pharmacodynamics, and efficacy in the diverse populations that may benefit from OXT, in particular those in whom hypothalamic OXT signaling may be abnormal or impaired (eg, individuals with Sim1 deficiency, Prader-Willi syndrome, or craniopharyngioma). Future studies will also have the opportunity to investigate the characteristics of new OXT mimetic peptides and the obligation to consider long-term effects, especially when OXT is given to children and adolescents. (Endocrine Reviews XX: XX - XX, 2020).

Misoprostol administration prior to intrauterine contraceptive device insertion: a systematic review and meta-analysis of randomised controlled trials

Objectives: Misoprostol has been used before intrauterine contraceptive device (IUCD) insertion to prime the cervical os. As the literature about this topic is controversial, we aimed to evaluate IUCD insertion failure, women's pain perception, use of cervical dilators and prevalence of side effects following the administration of misoprostol.Methods: Trials published in MEDLINE, Scopus, the Cochrane Library and ClinicalTrials.gov were searched (last search on 23 October 2019). The primary outcome was IUCD insertion failure; secondary outcomes were women's pain perception, use of cervical dilators to facilitate insertion, and prevalence of side effects.Results: Fourteen studies were eligible for inclusion. Misoprostol premedication reduced IUCD insertion failure rates and the use of cervical dilators but significantly increased the prevalence of side effects. The risk of IUCD insertion failure with misoprostol premedication was reduced among women who had undergone previous caesarean section and among women who had experienced previous IUCD insertion failure. Nulliparas did not benefit from misoprostol premedication. Buccal misoprostol administration did not seem to be effective in reducing IUCD insertion failure. Visual analogue scale pain scores were increased with both sublingual and buccal misoprostol administration if IUCD insertion was performed ≤2.5 h after misoprostol premedication.Conclusion: Our data demonstrate reduced IUCD insertion failure among women with previous caesarean section and those with previous IUCD insertion failure, suggesting that misoprostol may be a reasonable choice in these groups of women. Although misoprostol premedication reduced insertion failures, it significantly increased side effects and had a heterogeneous pattern of efficacy; thus, its routine use is not supported by the evidence.

Electro-Mechanical Ionic Channel Modeling for Uterine Contractions and Oxytocin Effect during Pregnancy

Uterine contractions during normal pregnancy and preterm birth are an important physiological activity. Although the cause of preterm labor is usually unknown, preterm birth creates very serious health concerns in many cases. Therefore, understanding normal birth and predicting preterm birth can help both newborn babies and their families. In our previous work, we developed a multiscale dynamic electrophysiology model of uterine contractions. In this paper, we mainly focus on the cellular level and use electromyography (EMG) and cell force generation methods to construct a new ionic channel model and a corresponding mechanical force model. Specifically, the ionic channel model takes into consideration the knowledge of individual ionic channels, which include the electrochemical and bioelectrical characteristics of individual myocytes. We develop a new sodium channel and a new potassium channel based on the experimental data from the human myometrium and the average correlations are 0.9946 and 0.9945, respectively. The model is able to generate the single spike, plateau type and bursting type of action potentials. Moreover, we incorporate the effect of oxytocin on changing the properties of the L-type and T-type calcium channels and further influencing the output action potentials. In addition, we develop a mechanical force model based on the new ionic channel model that describes the detailed ionic dynamics. Our model produces cellular mechanical force that propagates to the tissue level. We illustrate the relationship between the cellular mechanical force and the intracellular ionic dynamics and discuss the relationship between the application of oxytocin and the output mechanical force. We also propose a simplified version of the model to enable large scale simulations using sensitivity analysis method. Our results show that the model is able to reproduce the bioelectrical and electromechanical characteristics of uterine contractions during pregnancy.

Oxytocin Guidelines Associated with Compliance to National Standards

OBJECTIVE

Develop a multidisciplinary, consensus-driven, evidence-based approach to oxytocin use, while adhering to national guidelines.

DESIGN

This was a quality improvement project that used the Plan Do Study Act method to create cycles of change over several years. To initiate discussion, a survey was administered at a social event for providers from divergent community practices that addressed the controversial aspects of oxytocin use. Graphic feedback was provided showing divergences between answers and the evidence. The perinatal team directed design and implementation of this project with specific involvement of a nurse quality improvement coordinator and nurse educator.

MEASURES

Process, outcome, and balancing measures were used to evaluate the program. Process measure: use of a standardized order-set.

OUTCOME MEASURE

rate of adherence to the resultant protocol. Balancing measures: 1) maximum oxytocin dose, 2) time from oxytocin initiation to birth, 3) cesarean birth rates, and 4) Apgar scores.

RESULTS

An initial increase in adherence to the protocol decreased with the loss of the "paper" order-set. Adherence improved when computerized physician order entry was adjusted: 2006: 73%, 2007: 95%; 2011: 57%, 2013: 100% (p = 0.007, 2006 vs. 2007) (p < 0.001, 2006 vs. 2013). Compliance with the protocol was associated with a decrease in maximum oxytocin dose and in time between oxytocin initiation and birth (p < 0.001).

CONCLUSION

Consistency and safety in patient care can be accomplished using literature-based evidence and active consensus building among members of the perinatal team. A standardization process must be integrated into the electronic medical record to become a sustained part of a practice culture.

Systematic review of prostaglandin analogues for retained placenta

BACKGROUND

Medical management of retained placenta could be a safe alternative to manual removal.

OBJECTIVE

To evaluate the efficacy of prostaglandin analogues for retained placenta.

SEARCH STRATEGY

MEDLINE, EMBASE, CENTRAL, ICTRP, LILACS, and OpenSIGLE were searched without language restrictions from inception to January 31, 2017, by combining terms for retained placenta and prostaglandin analogues.

SELECTION CRITERIA

Randomized controlled trials comparing prostaglandin analogues with any other intervention.

DATA COLLECTION AND ANALYSIS

Trials were independently assessed for inclusion, data extraction, and risk of bias. Data were extracted for meta-analyses. GRADE was used to evaluate the quality of data.

MAIN RESULTS

Seven randomized controlled trials (851 patients) were included. Prostaglandins did not increase the placenta expulsion rate (relative risk [RR] 1.40, 95% confidence interval [CI] 0.83-2.36) or decrease maternal transfusion (RR 0.72, 95% CI 0.43-1.22). In comparison with oxytocin, prostaglandins did not modify the expulsion rate (RR 1.26, 95% CI 0.90-1.78), maternal transfusion (RR 1.05, 95% CI 0.27-4.09), or time for delivery of placenta (mean difference -1.56 minutes, 95% CI, -9.25-6.13). Three trials comparing prostaglandins with oxytocin agonists, ergometrine, and manual removal reported similar results.

CONCLUSIONS

Prostaglandin analogues do not offer an effective alternative for management of retained placenta.

Intranasal Oxytocin Does Not Modulate Responses to Alcohol in Social Drinkers

BACKGROUND

Preclinical and clinical evidence suggest that the neuropeptide oxytocin may be of value in treating alcohol use disorder, by either reducing the rewarding effects of alcohol or reducing negative affect induced by alcohol withdrawal. However, the effect of a single dose of oxytocin on subjective and psychomotor responses to alcohol in social drinkers is not known.

METHODS

This study examined the effect of intranasal oxytocin on subjective, behavioral, and physiological responses to a moderate dose of alcohol (0.8 g/kg) in young adult social drinkers. Participants (N = 35) completed 2 study sessions at which they consumed beverages containing alcohol (ALC; N = 20) or placebo (NoALC; N = 15) in combination with intranasal oxytocin (40 IU with a 20 IU booster) or placebo. They received oxytocin at one session and placebo at the other session (order counterbalanced) 20 minutes before consuming beverages. Subjective mood and drug effects ratings, heart rate and blood pressure, and 4 behavioral tasks (flanker task, digit span, go/no-go, and pursuit rotor) were the primary outcome measures.

RESULTS

ALC produced its expected subjective and behavioral effects; including feeling intoxicated and impaired performance on the digit span and go/no-go tasks. Oxytocin alone had no significant subjective or physiological effects, and it did not affect responses to alcohol on any measure.

CONCLUSIONS

We can conclude that, under these conditions, a single dose of intranasal oxytocin does not alter the effects of acute alcohol in healthy young adult social drinkers. Further research is needed to determine whether oxytocin alters responses to alcohol under different conditions, and to determine its potential as an aid in treatment for substance use disorders.

Contraction frequency after administration of misoprostol in obese versus nonobese women

Objective: To examine impact of obesity on contraction frequency following misoprostol. Our hypothesis is that an increased volume of distribution reduces the bioavailability of misoprostol and may be an explanation for reduced efficacy. We examined the contraction frequency as a surrogate marker for bioavailability of misoprostol. Study design: We compared the rate of contractions at five time intervals in 313 subjects: prior to administration, and at four intervals post administration. We compared number of contractions in obese versus nonobese. As a planned secondary analysis, we then compared the rate of change in contractions per hour at four time intervals: a repeated measures analysis to compare the rate of change in contractions per hour over the 5-hour window controlling for race (White versus non-White) and parity (primiparous versus multiparous). General linear model and repeated measures analysis were conducted to report the parameter estimates, least square means, difference of least square means, and p values. Results: Nonobese women presented with more contractions at baseline, 7 ± 5 versus 4 ± 5 c/h, p < .001. At all four time intervals after misoprostol administration obese women had fewer contractions per hour. The rate of change in contraction frequency after administration found obese women had a lower rate of increase in contraction frequency over the course of all four hours. We found a least squares means estimate (c/h): first hour (-0.87), p = .08, second hour (-2.43), p = .01, third hour (-1.80), p = .96, and fourth hour (-2.98), p = .007. Conclusions: Obese women have a lower rate of contractions per hour at baseline and at four intervals after misoprostol administration. In addition, the rate of change in the increase in contractions/hour also was reduced in obese women versus nonobese women. This suggests a lower bioavailability of misoprostol in women with a larger volume of distribution which would likely impact the efficacy of misoprostol in obese women when given the same dose of misoprostol. It is unknown if higher misoprostol dosing would increase efficacy of misoprostol in obese women.

Uterotonic Medications: Oxytocin, Methylergonovine, Carboprost, Misoprostol

Uterine atony is a common cause of primary postpartum hemorrhage, which remains a major cause of pregnancy-related mortality for women worldwide. Oxytocin, methylergonovine, carboprost, and misoprostol are commonly used to restore uterine tone. Oxytocin is the first-line agent. Methylergonovine and carboprost are both highly effective second-line agents with severe potential side effects. Recent studies have called into question the effectiveness of misoprostol as an adjunct to other uterotonic agents, but it remains a useful therapeutic in resource-limited practice environments. We review the current role these medications play in the prevention and treatment of uterine atony.

Titration of Intravenous Oxytocin Infusion for Postdates Induction of Labor Across Body Mass Index Groups

OBJECTIVE

To evaluate whether oxytocin titration for postdates labor induction differs among women who are normal weight, overweight, and obese and whether length of labor and birth method differ by oxytocin titration and body mass index (BMI).

DESIGN

Retrospective cohort study.

SETTING

U.S. university-affiliated hospital.

PARTICIPANTS

Of 280 eligible women, 21 were normal weight, 134 were overweight, and 125 were obese at labor admission.

METHODS

Data on women who received oxytocin for postdates induction between January 1, 2013 and June 30, 2013 were extracted from medical records. Oxytocin administration and labor outcomes were compared across BMI groups, controlling for potential confounders. Data were analyzed using χ², analysis of variance, analysis of covariance, and multiple linear and logistic regression models.

RESULTS

Women who were obese received more oxytocin than women who were overweight in the unadjusted analysis of variance (7.50 units compared with 5.92 units, p = .031). Women who were overweight had more minutes between rate changes from initiation to maximum than women who were obese (98.19 minutes compared with 83.39 minutes, p = .038). Length of labor increased with BMI (p = .018), with a mean length of labor for the normal weight group of 13.96 hours (standard deviation = 8.10); for the overweight group, 16.00 hours (standard deviation = 7.54); and for the obese group, 18.30 hours (standard deviation = 8.65). Cesarean rate increased with BMI (p = .001), with 4.8% of normal weight, 33.6% of overweight, and 42.4% of obese women having cesarean births.

CONCLUSION

Women who were obese and experienced postdates labor induction received more oxytocin than women who were non-obese and had longer length of labor and greater cesarean rates.

Identification of myoelectric signals of pregnant rat uterus: new method to detect myometrial contraction

Aim

To develop an electromyography method for pregnant rat uterus in vivo and to separate myometrial signals from the gastrointestinal tract signals.

Methods

Pregnant Sprague-Dawley rats (n = 8) were anaesthetized and their stomach, small intestine, and large intestine were removed from the abdomen. A pair of thread electrodes was inserted into the uterus, while a pair of disk electrodes was placed subcutaneously above the myometrium. Additionally, a strain gauge sensor was fixed on the surface of the myometrium and cecum for the parallel detection of mechanical contractions in rats (n = 18) with intact gastrointestinal tract. The filtered electric signals were amplified and recorded by an online computer system and analyzed by fast Fourier transformation. The frequency of the electric activity was characterized by cycle per minute (cpm), the magnitude of the activity was described as power spectrum density maximum (PsD_max).

Results

The frequency of the pregnant uterine activity was 1-3 cpm, which falls within the same range as that of cecum. Measuring by both electrodes, oxytocin (1 µg/kg) increased and terbutaline (50 µg/kg) decreased the PsD_max by 25%-50% (P < 0.001) and 25%-40% (P < 0.01), respectively. We found a strong positive correlation between the alterations of PsD_max values and the strain gauge sensor-detected mechanical contractions (area under curve). The GI specific compounds (neostigmine, atropine) mainly affected the cecal activity, while myometrium specific drugs (oxytocin, terbutaline) influenced the myometrial signals only.

Conclusion

Our method proved to be able to detect the myoelectric activity that reflects the mechanical contraction. The overlapping myometrial and cecal signals are not separable, but they can be distinguished based on the much higher activity and different pharmacological reactivity of the pregnant uterus. Thus, the early signs of contractions can be detected and labor may be predicted in a fast and sensitive way.

Outpatient cervical ripening

Induction of labor is one of the most commonly performed obstetric procedures. Many patients undergoing labor induction require cervical ripening. In an era where cost and patient satisfaction have become paramount, the idea of outpatient cervical ripening is appealing; provided it can be performed in a safe and cost effective manner. The ideal agent would induce adequate cervical ripening without causing significant uterine contractions/labor. Various methods have been studied including administration of misoprostol, PGE2, nitric oxide donors, use of Foley balloon catheters and acupuncture. Each method has its strengths and limitations; however, larger studies of outpatient cervical ripening that are specifically powered for rare adverse maternal and fetal outcomes are needed before definitive recommendations can be made.

Mechanisms of chorioamnionitis-associated preterm birth: interleukin-1β inhibits progesterone receptor expression in decidual cells

In chorioamnionitis (CAM), a major cause of preterm birth (PTB), maternal-fetal inflammation of the decidua and amniochorion cause the release of cytokines that elicit cervical ripening, fetal membrane rupture and myometrial activation. We posit that this inflammatory milieu triggers PTB by inhibiting progesterone receptor (PR) expression and increasing decidual prostaglandin (PG) production. Immunohistochemical staining of decidua detected significantly lower PR levels in decidual cells (DCs) from CAM-complicated PTB. Incubation of DCs with IL-1β decreased PR expression and significantly increased PGE2 and PGF2α production and COX-2 expression. The addition of PGF2α to DC cultures also suppressed PR expression. However, the COX inhibitor, indomethacin, did not reverse IL-1β suppression of PR expression in DC cultures. Although IL-1β treatment activated the NF-KB, ERK1/2 and p38 MAPK signalling cascades in DCs, inhibition of ERK1/2 MAPK signalling alone was sufficient to completely reverse the suppression of PR levels by IL-1β. These findings suggest that CAM-associated PTB is induced at least in part by IL-1β-mediated functional progesterone withdrawal.

Pharmacologic intervention for retained placenta: a systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness and safety of pharmacologic interventions for the treatment of retained placenta (when the placenta remains undelivered after 30 minutes of active management of the third stage of labor).

DATA SOURCES

We searched: 1) Cochrane Central Register of Controlled Trials (CENTRAL), 2) Cochrane Pregnancy and Childbirth Group's Trials Register, 3) EMBASE, and 4) MEDLINE from inception to June 2014.

METHODS OF STUDY SELECTION

Randomized controlled trials comparing a pharmacologic intervention(s) with a placebo for the treatment of retained placenta were included.

TABULATION, INTEGRATION, AND RESULTS

Sixteen randomized controlled trials, including 1,683 participants, were included. Study characteristics and quality were recorded. The meta-analysis was based on random-effects methods for pooled data. There were no statistically significant differences in the requirement to perform manual removal of a placenta in patients treated with oxytocin (55% compared with 60%; relative risk [RR] 0.86, 95% confidence interval [CI] 0.73-1.02; 10 randomized controlled trials [RCTs]), prostaglandins (44% compared with 55%; RR 0.82, 95% CI 0.58-1.15; four RCTs), nitroglycerin (85% compared with 80%; RR 1.06, 95% CI 0.80-1.41; one RCT), or oxytocin and nitroglycerin (52% compared with 79%; RR 0.23, 95% CI 0.01-8.48; two RCTs) compared with placebo. There was limited reporting of secondary outcomes.

CONCLUSION

As opposed to the use of oxytocin as part of the active management of the third stage of labor that has been shown to diminish bleeding in the third stage, once the diagnosis of retained placenta has been made, no pharmacologic treatment has been shown to be effective. When retained placenta is diagnosed, immediate manual removal of the placenta should be considered.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews, http://www.crd.york.ac.uk/PROSPERO/, CRD42014010641.

Expression of the prostaglandin F synthase AKR1B1 and the prostaglandin transporter SLCO2A1 in human fetal membranes in relation to spontaneous term and preterm labor

BACKGROUND

Human labor is a complex series of cellular and molecular events that occur at the materno-fetal and uterine levels. Many hypotheses have been proposed for the initiation of human labor, one hypothesis suggests that maturation of the fetus releases a signal in the amniotic fluid that will be transmitted to myometrium via the fetal membranes and initiate uterine contractions. There is strong evidence that prostaglandins (PGs) play a central role in initiation and progression of human labor.

OBJECTIVES

In this study we intended to investigate the expression of prostaglandin F synthase and the prostaglandin transporter in the human fetal membranes and to explore the relationship between cytokines and PGs in the mechanism of human labor.

METHODS

We used fetal membranes obtained before labor at term and after spontaneous labor at term or preterm to identify the changes in prostaglandin F synthase (AKR1B1) and human prostaglandin transporter (SLCO2A1) proteins in relation to parturition. Using fetal membranes explants we tested the effect of cytokines (interleukin-1 and tumor necrosis factor alpha) on PG production and the concomitant changes in cyclooxygenase-2 (PTGS2), AKR1B1 and SLCO2A1 expression.

RESULTS

Expression of PTGS2 and AKR1B1 was upregulated in the fetal membranes in association with term labor while SLCO2A1 was downregulated with advancing gestation and during term labor. Before labor, IL-1 increased the expression of PTGS2, however during labor TNF upregulated PTGS2 and AKR1B1 proteins.

CONCLUSIONS

The prostaglandin F synthase AKR1B1 is upregulated while prostaglandin transporter is downregulated during term labor. The amnion is more responsive than choriodecidua to stimulation with pro-inflammatory cytokines. The mechanisms of term and preterm labor are different.

Prostaglandins for management of retained placenta

BACKGROUND

Retained placenta affects 0.5% to 3% of women following delivery and it is a major cause of maternal death due to postpartum haemorrhage. Usually, retained placenta has been managed by manual removal or curettage under anaesthesia, which may be associated with haemorrhage, infection and uterine perforation. Medical management to facilitate the delivery of the retained placenta could be a safe alternative avoiding surgical intervention.

OBJECTIVES

To assess the effectiveness and safety of prostaglandins for the management of retained placenta.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 December 2013), LILACS (1982 to 1 December 2013), SciELO (1998 to 1 December 2013), Web of Science (2001 to 1 December 2013), openSIGLE (1997 to 1 December 2013), World Health Organization International Clinical Trials Registry Platform (ICTRP) (1 December 2013) and the metaRegister of Controlled Trials (mRCT) (1 December 2013). We also contacted authors of included studies and reviewed the reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled clinical trials comparing the use of prostaglandins (or prostaglandin analogues) with placebo, expectant management, tocolytic drugs, any other prostaglandins or surgical interventions for the management of retained placenta after vaginal delivery of singleton live infants of 20 or more weeks of gestation.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and assessed trial quality. Two review authors independently extracted data. Data were checked for accuracy. Any disagreements were resolved through consensus or consultation with a third review author when required. Authors of the included studies were contacted for additional information.

MAIN RESULTS

We included three trials, involving 244 women. The studies were considered to be at high risk of bias.The prostaglandins used were PG E2 analogue (sulprostone) in 50 participants and PG E1 analogue (misoprostol) in 194 participants at a dose of 250 mcg and 800 mcg respectively. The prostaglandins compared with placebo, were not superior in reducing the rate of manual removal of placenta (average risk ratio (RR) 0.82; 95% confidence interval (CI) 0.54 to 1.27), severe postpartum haemorrhage (RR 0.80; 95% CI 0.55 to 1.15), need for blood transfusion (RR 0.72; 95% CI 0.43 to 1.22), mean blood loss (mean difference (MD) -205.26 mL; 95% CI -536.31 to 125.79, random-effects) and the mean time from injection to placental removal (MD -7.00 minutes; 95% CI -21.20 to 7.20). Side-effects were no different between groups (vomiting, headache, pain and nausea between injection and discharge from the labour ward), with the exception of shivering, which was more frequent in women receiving prostaglandins (RR 10.00; 95% CI 1.40 to 71.49). We did not obtain any data for the primary outcomes of maternal mortality and the need to add another therapeutic uterotonic.

AUTHORS' CONCLUSIONS

Currently there is limited, very low-quality evidence relating to the effectiveness and the safety using prostaglandins for the management of retained placenta. Use of prostaglandins resulted in less need for manual removal of placenta, severe postpartum haemorrhage and blood transfusion but none of the differences reached statistical significance. Much larger, adequately powered studies are needed to confirm that these clinically important beneficial effects are not just chance findings.Similarly, no differences were detected between prostaglandins and placebo in mean blood loss or the mean time from injection to placental removal (minutes) or side-effects (vomiting, headache, pain and nausea between injection and discharge from the labour ward) except for 'shivering' which was more frequent in women who received prostaglandin. The included studies were of poor quality and there is little confidence in the effect estimates; the true effect is likely to be substantially different. We can not make any recommendations about changes to clinical practice. More high-quality research in this area is needed.

Beyond labor: the role of natural and synthetic oxytocin in the transition to motherhood

Emerging research raises questions that synthetic oxytocin during childbirth may alter the endogenous oxytocin system and influence maternal stress, mood, and behavior. Endogenous oxytocin is a key component in the transition to motherhood, affecting molecular pathways that buffer stress reactivity, support positive mood, and regulate healthy mothering behaviors (including lactation). Synthetic oxytocin is widely used throughout labor and postpartum care in modern birth. Yet research on the implications beyond labor of maternal exposure to perinatal synthetic oxytocin is rare. In this article, we review oxytocin-related biologic pathways and behaviors associated with the transition to motherhood and evidence supporting the need for further research on potential effects of intrapartum oxytocin beyond labor. We include a primer on oxytocin at the molecular level.

The EPIIC hypothesis: intrapartum effects on the neonatal epigenome and consequent health outcomes

There are many published studies about the epigenetic effects of the prenatal and infant periods on health outcomes. However, there is very little knowledge regarding the effects of the intrapartum period (labor and birth) on health and epigenetic remodeling. Although the intrapartum period is relatively short compared to the complete perinatal period, there is emerging evidence that this time frame may be a critical formative phase for the human genome. Given the debates from the National Institutes of Health and World Health Organization regarding routine childbirth procedures, it is essential to establish the state of the science concerning normal intrapartum epigenetic physiology. EPIIC (Epigenetic Impact of Childbirth) is an international, interdisciplinary research collaboration with expertise in the fields of genetics, physiology, developmental biology, epidemiology, medicine, midwifery, and nursing. We hypothesize that events during the intrapartum period - specifically the use of synthetic oxytocin, antibiotics, and cesarean section - affect the epigenetic remodeling processes and subsequent health of the mother and offspring. The rationale for this hypothesis is based on recent evidence and current best practice.

Use of oxytocin during Caesarean section at Princess Marina Hospital, Botswana: An audit of clinical practice

Background

Oxytocin is widely used for the prevention of postpartum haemorrhage. In the setting of Caesarean section (CS), the dosage and mode of administrating oxytocin differs according to different guidelines. Inappropriate oxytocin doses have been identified as contributory to some cases of maternal deaths. The main aim of this study was to audit the current standard of clinical practice with regard to the use of oxytocin during CS at a referral hospital in Botswana.

Methods

A clinical audit of pregnant women having CS and given oxytocin at the time of the operation was conducted over a period of three months. Data included indications for CS, oxytocin dose regimen, prescribing clinician's designation, type of anaesthesia for the CS and estimated blood loss.

Results

A total of 139 case records were included. The commonest dose was 20 IU infusion (31.7%). The potentially dangerous regimen of 10 IU intravenous bolus of oxytocin was used in 12.9% of CS. Further doses were utilized in 57 patients (41%). The top three indications for CS were fetal distress (36 patients, 24.5%), dystocia (32 patients, 21.8%) and a previous CS (25 patients, 17.0%). Estimated blood loss ranged from 50 mL – 2000 mL.

Conclusion

The use of oxytocin during CS in the local setting does not follow recommended practice. This has potentially harmful consequences. Education and guidance through evidence based national guidelines could help alleviate the problem.

Vaginal misoprostol aids in difficult intrauterine contraceptive removal: a report of three cases

BACKGROUND

Intrauterine devices are the most used long-acting reversible contraceptive method worldwide. Under normal circumstances, removal of an intrauterine contraceptive (IUC) is an uncomplicated procedure requiring gentle traction on the string.

STUDY DESIGN

We report three cases of nonvisible IUC strings where, following use of vaginal misoprostol, the IUC strings were visualized and the IUCs were removed intact with gentle traction.

CONCLUSIONS

The uterotonic and uterocontractile effects following vaginal misoprostol facilitated removal in three cases of nonvisible IUC strings. We suggest that clinicians consider including vaginal misoprostol alone or prior to planned repeat office or procedure-clinic interventions for nonvisible IUC strings.

Clinicians' guide to the use of oxytocin for labor induction and augmentation

Oxytocin is commonly used in obstetrics for labor induction and augmentation. Careful assessment of the individual clinical situation based on indications and contraindications is essential to enhancing safe and effective use. Counseling the woman and her partner regarding potential risks and benefits before use is necessary to promote informed consent. At least 39 weeks of gestation is required for elective labor induction. Recent research has shown that deferring elective induction until cervical readiness has been achieved without the use of pharmacologic agents can be beneficial in reducing the risk of cesarean birth associated with elective induction. A conservative physiologic oxytocin protocol for labor induction and augmentation is recommended to minimize the risk of side effects. Although treatment of excessive uterine activity related to oxytocin has not been studied prospectively, several interventions such as maternal repositioning, an intravenous fluid bolus, and discontinuation of the oxytocin infusion are beneficial in returning uterine activity to normal, based on retrospective review of oxytocin-induced tachysystole. Perinatal quality measures from the National Quality Forum and the Joint Commission can be useful in monitoring care related to induction of labor. These include elective births before 39 weeks of pregnancy and cesarean births for low-risk, first-birth mothers.

Low Dose Vaginal Misoprostol in the Management of Women with Intrauterine Fetal Death

Objectives

The study was conducted to assess the effectiveness and side effects of vaginal misoprostol (Vagiprost® tablet) in termination of second and third trimester pregnancy complicated with intrauterine fetal death.

Design

A prospective observational cohort study.

Setting

Tanta University Hospital.

Patients

The study was carried out on 324 women with fetal demise in the second and third trimesters. Cases were collected during the period from January 2008 to December 2009.

Intervention

All patients were subjected to history taking, physical examination, Bishop Scoring. Application of 25 μg misoprostol in the posterior fornix of the vagina, this will be repeated every 4 hours over 24 hours. The adverse effects, progress, and outcomes were assessed.

Results

the success rate was 90% and 45% in women with third and second trimesters respectively. The mean induction-termination interval was 8.95 ± 2.63 and 15.3 ± 5.37 hours for women with third and second trimesters respectively. The induction termination interval correlated negatively with the duration of gestation. Approximately, 90% of second trimester and 55% of third trimester women required oxytocin augmentation. The mean value of total required dose of misoprostol was 166.3 ± 7.5 and 120 ± 28.79 μg for women with second and third trimesters respectively.

Conclusion

Vagiprost appears to be a safe, effective, practical, and inexpensive method for termination of third trimester pregnancy complicated with of intrauterine fetal death (IUFD), its effects increase with parity and duration of gestation.

High fever following postpartum administration of sublingual misoprostol

Objective

To explore what triggers an elevated body temperature of ≥40.0°C in some women given misoprostol, a prostaglandin E1 analogue, for postpartum haemorrhage (PPH).

Design

Post hoc analysis.

Setting

One tertiary-level hospital in Quito, Ecuador.

Population

A cohort of 58 women with a fever of above 40°C following treatment with sublingual misoprostol (800 micrograms) for PPH.

Methods

Side effects were documented for 163 Ecuadorian women given sublingual misoprostol to treat their PPH. Women’s body temperatures were measured, and if they had a fever of ≥40.0°C, measurements were taken hourly until the fever subsided. Temperature trends were analysed, and the possible physiological mechanisms by which postpartum misoprostol produces a high fever were explored.

Main outcome measures

The onset, duration, peak temperatures, and treatments administered for cases with a high fever.

Results

Fifty-eight of 163 women (35.6%) treated with misoprostol experienced a fever of ≥40.0°C. High fevers followed a predictable pattern, often preceded by moderate/severe shivering within 20 minutes of treatment. Body temperatures peaked 1–2 hours post-treatment, and gradually declined over 3 hours. Fevers were transient and did not lead to any hospitalisation. Baseline characteristics were comparable among women who did and did not develop a high fever, except for known previous PPH and time to placental expulsion.

Conclusions

An unexpectedly high rate of elevated body temperature of ≥40.0°C was documented in Ecuador following sublingually administered misoprostol. It is unclear why temperatures ≥40.0°C occurred with a greater frequency in Ecuador than in other study populations using similar treatment regimens for PPH. Pharmacogenetic studies may shed further light on variations in individuals’ responses to misoprostol.

A combination of misoprostol and estradiol for preoperative cervical ripening in postmenopausal women: a randomised controlled trial

OBJECTIVE

To compare the impact of 1000 microg of self-administered vaginal misoprostol versus self-administered vaginal placebo on preoperative cervical ripening after 2 weeks of pretreatment with estradiol vaginal tablets in postmenopausal women prior to day-care operative hysteroscopy.

DESIGN

Randomised, double-blind, placebo-controlled sequential trial.

SETTING

Norwegian university teaching hospital.

POPULATION

Sixty-seven postmenopausal women referred for day-care operative hysteroscopy.

METHODS

The women were randomised to receive either 1000 microg of self-administered vaginal misoprostol or self-administered vaginal placebo on the evening before day-care operative hysteroscopy. All women had administered a 25-microg vaginal estradiol tablet daily for 14 days prior to the operation.

MAIN OUTCOME MEASURES

PRIMARY OUTCOME

preoperative cervical dilatation at hysteroscopy.

SECONDARY OUTCOMES

difference in dilatation at recruitment and before hysteroscopy, number of women who achieved a preoperative cervical dilatation of 5 mm or more, acceptability, complications and adverse effects.

RESULTS

The mean cervical dilatation was 5.7 mm (SD, 1.6 mm) in the misoprostol group and 4.7 mm (SD, 1.5 mm) in the placebo group, the mean difference in cervical dilatation being 1.0 mm (95% CI, 0.2-1.7 mm). Self-administered vaginal misoprostol of 1000 microg at home on the evening before day-care hysteroscopy is safe and highly acceptable, although a small proportion of women experienced lower abdominal pain.

CONCLUSIONS

One thousand micrograms of self-administered vaginal misoprostol, 12 hours prior to day-care hysteroscopy, after 14 days of pretreatment with vaginal estradiol, has a significant cervical ripening effect compared with placebo in postmenopausal women.

Can vaginal misoprostol effectively increase rate of a satisfactory colposcopy? A randomized double-blind placebo-controlled trial

OBJECTIVE

To evaluate the effectiveness of vaginal misoprostol in overcoming an unsatisfactory colposcopy in the patients who had abnormal cervical cytology and to evaluate side effects of vaginal misoprostol.

METHODS

Sixty patients with an unsatisfactory colposcopy during the period of September 2007-November 2008 were recruited and randomly allocated to receive either two tablets of 200 microg misoprostol (400 microg) or two tablets of similar-looking placebo vaginally. Colposcopic re-examination was performed approximately 6 h later. The results and side effects before and 2 weeks after the colposcopic re-examination were recorded.

RESULTS

Six out of 30 patients in the misoprostol group (20.0%) had a satisfactory colposcopic re-examination compared with 2 out of 27 patients (7.4%) in the placebo group without statistically significant difference (P = 0.172). Three patients in the placebo group dropped out due to not present at the appointment time. Six out of 30 patients (20.0%) and 1 out of 30 patients (3.3%) in the misoprostol group had side effects before and 2 weeks after the colposcopic re-examination orderly. Twenty-seven patients in the placebo group did not have any side effects before and 2 weeks after the colposcopic re-examination. All side effects occurred were minimal and well tolerated.

CONCLUSIONS

Four hundred micrograms of vaginal misoprostol were not proved to be effective in converting an unsatisfactory to a satisfactory colposcopy.