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The current paradigm in obstetrics has shifted toward evidence-based medicine, and yet in clinical practice physicians continue to use interventions for which there exists no credible evidence. This article examines the U.S. Food and Drug Administration (FDA) status of home uterine activity monitoring (HUAM) and the published clinical trials examining HUAM for the management of current preterm labor. The use of HUAM was introduced into clinical practice and heavily marketed without benefit of scientific rigor. Gradually, HUAM use migrated primarily for patients diagnosed (or misdiagnosed) with preterm labor in the current pregnancy who are stabilized and sent home with or without a tocolytic. This clinical intervention has not been cleared by the FDA, has virtually no scientific support, and constitutes a gross deviation from evidence-based medicine. As obstetricians accept the role of medical evidence steering clinical practice, HUAM clearly has no clinical value and therefore should not be used to manage patients outside of a randomized controlled clinical trial.

Aim: To summarize the currently available knowledge on (1) the methods to monitor uterine activity (UA); (2) the units to quantify UA; and (3) to assess the importance of abnormal contraction patterns on the condition of the fetus. The need for correct assessment and interpretation of the uterine contraction curve to improve fetal outcome will be emphasized. Study results: Correct assessment of the uterine contraction curve is an essential part of the cardiotocogram and should be obtained by the best method available; i.e., internal tocography (IT). IT provides objective information on quantization of UA and has the ability to obtain a good quality trace in an obese, restless patient. Accurate information on UA is essential because elevated UA during the first and second stage of labor can increase the risk of adverse fetal outcome. The relaxation time appears to be an important contraction parameter to maintain fetal well-being during labor. Almost all abnormal contraction patterns are characterized by shortening of the relaxation time and can lead to severe asphyxia. Duration, amplitude and frequency of contractions are of importance as well. The mean active pressure unit is the means to quantify UA since it incorporates these three contraction parameters. Conclusion: Proper application of UA monitoring by means of the internal method and adequate reading and interpretation of the uterine contraction curve is a prerequisite for high quality electronic fetal heart rate monitoring. © 2007 by Walter de Gruyter.

Aims: To determine the quality of intrapartum uterine activity (UA) monitoring in daily practice during the first and second stage of labor. The total duration of inadequate UA monitoring is quantified in relation to the technique applied: external or internal. Methods: One hundred and ninety-two UA recordings, collected from 1 April 2006 untill 1 October 2006 from consecutive deliveries at the Vrije Universiteit Medical Center in Amsterdam, were analyzed. Included recordings were from singleton, spontaneous, vaginal deliveries. The last two hours of the first stage and the complete second stage had to be monitored. Internal and external UA recordings were judged by their quality: adequate, a recognizable and reliable UA pattern during the complete registration, or inadequate. Recordings labeled as inadequate were divided into two groups: absence of UA recording (non recognizable) or inadequate calibration (unreliable). Statistical analyses were performed with the Mann-Whitney U-test and the Wilcoxon signed ranks test. Results: The percentages of adequate UA recordings in the first stage of labor were much higher for the internal than the external mode. Only 2% of the external recordings were of good quality vs. 40% of the internal recordings. In the second stage, percentages of adequate UA recordings were nearly equal, approximately 30%. Inadequate external registrations were characterized by almost 30% of the time absent UA monitoring, whereas with inadequate internal registrations the primary problem was correct calibration. Conclusion: Intrapartum UA monitoring in daily practice via the direct mode provides a more recognizable UA trace. © 2008 by Walter de Gruyter.

Premature birth is the leading cause of a neonatal death, so, it is extremely important to distinguish the pregnancy at risk of preterm threatening labour. The electrohysterography seems very promising as a method which enables noninvasive recording of readable bioelectrical signal of uterine muscle. The developed instrumentation enabled simultaneous recording of bioelectrical signals by means of electrodes attached to abdominal wall and mechanical activity of uterine muscle using fetal monitor. Material comprised 27 patients physiological pregnancy (27 ÷ 40 week), and 21 patients (23 ÷ 36 week) with the symptoms of threatening premature labour. The obtained results showed that quantitative parameters detected uterine contractions: amplitude and contraction area, obtained both for mechanical and electrical activity, were statistically significant (p < 0.05) to distinguish the patients risk of premature labour. However, their reliability is low because they strongly depend on individual patient features. We consider the parameters characteristic for electrohysterogram exclusively e.g. contraction power and its median frequency as more useful (p < 0.05). Noninvasive electrohysterography ensures higher sensitivity and specificity for recognition of uterine contraction activity in comparison classical mechanical method.

In an attempt to develop a reproducible, objective measure of adequate uterine activity in labor, real-time measurements of intrauterine pressure amplitude and contraction frequency, interval, duration, and integral were made in 54 patients, 11 of whom received oxytocin augmentation. We determined the active pressure integral required per centimeter of cervical dilatation, expressed in kPa seconds, and the mean active pressure, expressed in kPa. The augmented group had a significantly higher mean active pressure integral per centimeter than those in normal labor (P less than .01). There was a trend, which did not reach statistical significance, for subjects who required oxytocin augmentation of labor to develop a higher mean active pressure than those in normal labor. However, the correlation of any uterine contractility index (Montevideo units, Alexandria units, mean active pressure) with progress in labor was poor. We conclude that women with dysfunctional labor require more uterine activity for progress in labor than women with normally progressing labor, and that the computer-derived "area under the curve" is not a better predictor of labor progress than Montevideo units.

Myometrial electrography was performed by means of chronically implanted electrodes in the base, the middle and the tubal end of both the uterine horns of six Serres ewes at normal and progestogen-regulated estrus. During the first 24 h of normal estrus, myometrial electrical activity was characterized by intermittent spike bursts (Pattern I activity), occurring at about the same frequency in the three sites of both horns (middle of the right horn: 44.13 ± 6.07 / 30 min). This pattern was then gradually transformed so that 36 h after the beginning of estrus, there was mostly only episodic activity consisting of 18.22 ± 3.44 bursts, lasting 6.50 ± 2.42 mins, and recurring at 30.51 ± 16.24 min intervals simultaneously in both horns (Pattern II activity). During Patterns I and II, the respective ratios of descendingly to ascendingly propagated bursts were 2.65 and 0.78. Pattern I activity also occurred during the first 24 h of progestogen-regulated estrus, but the frequency of the bursts of spikes although occurring in the tubal ends of both horns at about the same rate as in Pattern I at normal estrus, gradually decreased towards the uterine body, (tubal end: 44.34 ± 4.28, middle: 40.14 ± 5.42, and base: 33.22 ± 4.82 / 30 min). Then Pattern I activity was transformed into a miscellaneous pattern instead of into Pattern II. In the progestogen-regulated estrus, the ratio of the descending to the ascending propagations of spikes during Pattern I activity rose to 5.11.

Summary There are, therefore, a multitude of concerns that require consideration with regard to providing anesthesia care for the pregnant patient undergoing surgery. However, the basic considerations common to all such cases are the following: (1) The physiologic changes of pregnancy must be understood and the anesthetic implications thereof must be acted upon. (2) Maternal blood pressure and uteroplacental perfusion must be maintained. Hypotension and aortocaval compression should be avoided; however, if these should occur, treatment should be instituted promptly. (3) Anesthetic techniques should be selected that limit the exposure of mother and fetus to potentially teratogenic agents; remembering, however, that no anesthetic agent has yet been proved to be teratogenic in man. Regional anesthesia should be used whenever possible. (4) Preoperatively, discuss with the patient the implications of surgery and anesthesia during pregnancy, including our current knowledge regarding the lack of known teratogenicity of anesthetic agents. (5) Fetal heart rate and uterine activity should be monitored intraoperatively and postoperatively; if changes are noted, the anesthetic technique should be modified accordingly.

The purpose of this study was to identify differences in antepartum uterine contraction frequency (UCF) in twin pregnancies with and without preterm labor (PTL).Twin gestations enrolled for outpatient surveillance with twice daily electronic uterine activity monitoring and telephonic nursing assessment, without interventional delivery were identified. Mean UCF for each gestational week was compared between women without PTL or preterm delivery (PTD)36 weeks (controls) and those with a PTL diagnosis delivering at36 weeks (PTL/PTD group), and those with PTL with deliveryor = 36 weeks (PTL/GADor = 36 group).Data from 7891 patients with 267,840 monitored hours were analyzed. UCF at each gestational week was significantly higher for patients experiencing PTL with or without PTD compared to control. UCF was similar for patients with PTL with or without PTD36.Twin pregnancies complicated with PTL have a higher UCF than those that do not experience PTL. Outpatient surveillance may be beneficial in this population.

We performed recording of the magnetic fields (Magnetomyography - MMG) corresponding to the electrical activity of the uterine smooth muscle with a device called SARA, (SQuid Array for Reproductive Assessment). Past studies suggest that the uterus passes through a preparatory process before entering labor and resulting in delivery of the fetus. But the electrophysiological mechanism of this process is not completely understood. We propose four parameters that will allow us quantify the characteristics of the uterine MMG signal obtained from 151 sensors spread over the pregnant abdomen. In summary, we believe that spatial-temporal analysis mapping of uterine activity will help us better understand the process of labor.

Oxytocin is extensively used to induce or augment uterine contractions, especially to facilitate the third stage of labor in humans. Administration of oxytocin to parturient sows reduces duration of labor whereas mortality of the offspring may remain unchanged. This study aimed to evaluate whether time of administration of oxytocin during parturition may alter the uterine response and fetal outcomes. Two hundred parturient sows were randomly assigned to intramuscularly receive either saline solution (control group) or oxytocin 0.083 IU/kg immediately after the delivery of the 1 st , 4 th or 8 th piglet (groups O-1, O-4 and O-8, respectively). Uterine effects and fetal outcomes were registered in all groups. The duration of labor was 20-40 min shorter (P < 0.0001) and time interval between babies was reduced by 3-5 min (P < 0.0001) in the three groups receiving oxytocin. The duration and intensity of contractions, meconium-stained piglets and intrapartum deaths decreased as time at which oxytocin administered during labor was increased. In group O-8, we observed approximately 70% less meconium-stained piglets and intrapartum deaths than in the control group. In conclusion, oxytocin administered at early phases of parturition to sows may increase duration and intensity of uterine contractions as well as adverse fetal outcomes.

Monitoring the uterine contractions provides important prognostic information during pregnancy and delivery. In particular, the propagation of uterine activity is closely related to the contraction efficiency. In the present study, a propagation analysis of uterine contraction is carried out by simultaneously recording the electrohysterogram (EHG) and the internal uterine pressure (TUP) on one woman in the last 4 hours of labor. The EHG, recorded in a monopolar multi- electrode configuration, was first processed in each channel in order to provide an accurate estimate of the IUP. The IUP estimate resulted in a correlation coefficient with the simultaneously recorded IUP r=0.74. Eventually, in order to evaluate the propagation of the muscular electrical activity, the delays among the IUP estimates in each channels were calculated by cross correlation function maximization. In agreement with previous studies, no preferred direction of propagation was singled out and pacemaker areas changed from contraction to contraction. However, by analyzing the occurrences of each pacemaker area, the uterine upper part resulted the most frequent location. Moreover, the close agreement between the number of simultaneously active electrodes and the IUP peak values (r=0.76) revealed a relationship between the spreading of action potentials and the maximum amplitude of contraction.

In 47 women, the change in the uterine activity after the administration of a uterotonic agent was correlated with the amount of blood loss during the same period of time. Uterine activity was measured by a Gaeltec® catheter-tipped pressure transducer inserted transcervically within 5 min of delivery of the placenta. A uterotonic agent (either intravenous syntocinon, intramuscular syntometrine or oral misoprostol) was given after the insertion of the intrauterine pressure catheter and pressure recorded for another 90 min. Blood loss over the same 2-hour period was collected with absorbent paper which was then assessed by colorimetric measurement of the haemoglobin content in the sample. Our results show that the change in uterine activity is associated with the total blood loss. However, there is a poor linear correlation between the two variables probably because of the biological variation in myometrial activity and differences in coagulation mechanisms in normal women.

A 40-year-old woman presented at 26 weeks' gestation in her fifth pregnancy with heightened uterine activity and suprapubic pain. She had previously had four uncomplicated caesarean deliveries. At ...

When a woman learns that she is pregnant, her emotions are like a roller coaster. To her, she is pregnant. She begins to plan all the things that could be and is in constant motion to await the 9 months until the arrival of her bundle of joy. However, to those of us in the perinatal nursing field, it means so much more. The pregnant woman's body goes through some profound anatomical, physiologic, and biochemical changes to adapt to and support the entire pregnancy, which ultimately support the growing fetus. Although these physiologic changes are normal, often they can be misinterpreted as disease. These changes may also unmask or worsen a preexisting condition or disease, ultimately because the pregnant woman's body cannot adequately adapt to the changes of pregnancy. It is essential to know and understand the physiology-the inner workings-of both the mother and the fetus. This includes the basic adaptations related to pregnancy, placental physiology and action, uterine activity physiology, and fetal heart rate regulation, although this article will focus on maternal and uterine physiology only.

Electrohysterography (EHG) is a promising tech- nique for monitoring the uterine activity, based on electrical recordings on the abdominal surface. However, a quantitative estimation of the internal uterine pressure (IUP) by means of EHG is not available for clinical practice. In this paper we present a preliminary study on the estimation of the mechanical uterine activity from abdominal EHG measurements. For the EHG analysis we use two different Time Frequency Distribu- tions (TFD): the spectrogram and the Wigner-Ville Distribution. We assume the EHG to be the sum of frequency modulated signals. Based on this assumption, the IUP is estimated from the unnormalized first moment of the TFD. Eventually, a third order polynomial model is applied to the estimated IUP in order to improve the estimate accuracy. A recent method for detection of uterine contraction by EHG is employed for comparison of the performance. The algorithms were tested on two patient recordings. The results were compared with a reference IUP which is simultaneously measured by an intrauterine catheter. The IUP estimated by our method showed a correlation coefficient with the reference IUP (R= 0.93) higher than that achieved by the comparison method (R= 0.85). Therefore the proposed method may be considered as a promising clinical technique for accurate non invasive IUP measurements.

The nonpregnant uterus shows uterine activity throughout the menstrual cycle. This uterine activity was detected both by single strep tissue and by using intrauterine pressure recordings in vitro and in vivo. Today, ultrasound has made it possible to study this activity with a noninvasive approach and to assess uterine contractions (UCs) in real-time movements of the uterus. Throughout the menstrual cycle, wavelike activity patterns of the reproductive organ were established. These patterns are under control of steroid hormones. Adequate UCs may provide for gamete/embryo transportation throughout the uterotubal cavities and successful embryo implantation in spontaneous and/or assisted reproduction. Inadequate UCs may produce ectopic pregnancy, miscarriages, retrograde bleeding with dysmenorrhea, and endometriosis.

This study aims to examine influences of specific boar stimuli on uterine activity in estrous sows, by comparing uterine activity in presence of a mature teaser boar and a robot boar with variable stimuli. Nineteen multiparous, cyclic, commercial crossbred sows were used. Intra-luminal uterine pressure was measured using a non-surgical method for 45 min before applying one of four treatments in combination with a back-pressure-test (BPT): (1) robot with olfactory and auditory stimuli (R + O + A) (n = 16), (2) robot with auditory stimuli (R + A) (n = 16), (3) robot without additional stimuli (R) (n = 16), (4) a mature boar (boar) (n = 15). After treatment, measurements continued for 30 min. For each measurement, frequency, mean amplitude and mean duration of uterine contractions were determined. Spontaneous frequency of uterine contractions was 18.6 ± 0.7 h¿1 on average and did not differ between treatments. Frequency of contractions increased significantly for the boar (+5.6 ± 1.3 h¿1; P

In 27 women, uterine activity in the third stage of labour was correlated with blood loss measured quantitatively during the same period of time. Myometrial activity was reflected by total intrauterine pressures measured using a Gaeltec® catheter tipped pressure transducer inserted transcervically within 5 min of delivery of the placenta. Blood loss over the same 2-hour period was collected on absorbent paper and measured in the laboratory by colorimetric measurement of the haemoglobin content. As total uterine activity in the third stage of labour decreases total blood loss increases, but there is a poor correlation of uterine activity to total blood loss over the same period of time, probably because of biological variations in myometrial activity in normal women.

The prevention of preterm labor has the potential to reduce newborn morbidity and mortality by decreasing the incidence of preterm birth. Half of all preterm births occur in women with no known clinical risk factors. Labor onset and progress is multifactorial, and we are just beginning to understand the role of cytokines in uterine activity. The purpose of this article is to review the role of cytokines in labor and preterm labor not associated with infection and to provide implications for research and practice.

Objective A critical analysis of the United States randomized controlled trial of fetal pulse oximetry concluded that nonreassuring fetal heart rate patterns used for study entry may have been a marker for dystocia. We prospectively studied nulliparous women in labor whose progress was monitored with fetal pulse oximetry to examine the relationship between nonreassuring fetal heart rate patterns and operative delivery for dystocia. Study design A prospective nonrandomized observational cohort study compared two distinct classes of nonreassuring fetal heart rate patterns (class I: intermittent, mildly nonreassuring; class II: persistent, progressive, and moderate to severely nonreassuring) among nulliparous patients with the use of fetal pulse oximetry to confirm fetal well-being. Definitions of dystocia included the cessation of labor progress in the first (3 hours) or second (2 hours) stage of labor, despite adequate uterine activity that was assessed with an intrauterine pressure catheter. Independent review confirmed the classification of nonreassuring fetal heart rate patterns and study entry criteria. Results Two hundred seventy-four patients met study criteria and had sufficient information for fetal heart rate tracing interpretation. Two hundred thirty-seven patients (86.5%) were class II, and 37 patients (13.5%) were class I. The two classes of patients were comparable in a variety of obstetric, demographic, and perinatal variables. Twelve percent of all patients were delivered for nonreassuring fetal status. Significantly more class II patients (22%) were delivered by cesarean for dystocia than were class I patients (8%). Higher doses and a longer number of hours of oxytocin were required among class II patients. Significantly more occiput posterior positions were noted among all patients who underwent cesarean delivery for dystocia compared with other modes of delivery. Conclusion Significantly nonreassuring fetal heart rate patterns predict cesarean delivery for dystocia among nulliparous patients with normally oxygenated fetuses in a setting of a standardized labor management protocol. This confirms the observations in the randomized controlled trial of fetal pulse oximetry in the United States and may provide insight into the treatment of nonprogressive labor in contemporary practice.

The non-pregnant uterus shows wave-like activity throughout the menstrual cycle. This uterine activity was first detected using intra-uterine pressure recordings. The use of ultrasound has made it possible to study the movements of the uterus in a non-invasive manner. Throughout the menstrual cycle, several wavelike activity patterns have been described; these patterns change throughout the menstrual cycle and are governed by steroid hormones. An adequate wave pattern seems to be related to successful reproduction in spontaneous cycles and assisted reproduction. Further insight into the phenomenon of endometrial wave-like activity might offer an opportunity to correct abnormal wave patterns and thereby improve pregnancy rates.

(1). To determine if participation in the Halifax County Preterm Birth Prevention Project (HCPBPP) reduced the risk of preterm birth; (2). to evaluate the degree to which specific components of the HCPBPP contributed to preterm-birth risk reduction.A nested case-control study was conducted among women residing in Halifax County who gave birth at the IWK Grace Health Centre during the final year of the HCPBPP. Cases, defined as women who delivered preterm (37 weeks), and controls, defined as women who delivered at full term, were recruited to complete interviewer-administered questionnaires. Three controls per case were sequentially selected. The exposures of interest were overall participation and compliance with specific components of the program. Univariate and multivariate statistical methods were employed to evaluate the effect of exposure to the preterm-birth prevention program.Seventy cases and 210 controls were enrolled in the study. Although 82% of subjects participated in some aspect of the HCPBPP, only 8% of high-risk and 6% of low-risk women complied fully with program recommendations. Exposure to project educational strategies or pelvic examinations provided no protective benefit for preterm birth in low-risk or high-risk women. However, compliance with prenatal care providers recommendations to restrict activity or monitor for uterine contractions by self-palpation was associated with a marked reduction in the risk of preterm birth among low-risk women (odds ratio, 0.20; 95% confidence interval, 0.08 0.50).Although full participation in the HCPBPP protocol was limited, the findings of this case-control study suggest that activity restriction and uterine activity monitoring by self-palpation may reduce the likelihood of preterm birth in women with no identifiable risk factors for prematurity.

An algorithm based on Four Nearest Neighborhood (4NN) method has been developed to get a colour coded image of the entire uterine activity during labour. A dedicated data acquisition system has been developed to pick up the uterine contractile potentials at 8 different positions of the uterus and 4NN technique has been applied to convert these 8 channels of information into a colour coded image of 320/spl times/320 pixels.

We propose a ridge extraction method, based on the local maxima of the scalogram, in order to follow the spectral components during time. The method is applied on a monkey's uterine electromyogram signal, which represents the electrical uterine activity during pregnancy. This signal possesses two spectral components, identified as FW/sub L/ and FW/sub H/ in the literature. Their extraction and characterization could be of great value to understand the woman's uterine activity, particularly for the medical diagnosis of preterm delivery.

Spontaneous depolarization and repolarization due to ionic currents are the main properties of smooth muscle cells in the uterus. Their functioning as contractile tissue depends on intercellular electrical and metabolic communication. Due to the lack of a depolarization conducting system, the relationship between the electrical and mechanical activity of the uterus is determined by the amount of contractile cells being activated at a time. Changes in the distribution of electrical charges create the electric fields manifested on an electrohysterogram (EHG). Since the waveforms observed in EHGs are subject-dependent, they cannot be compared between patients. However, for reliable use of EHGs in obstetrics there is a strong need to establish methods of tracking selected parameters of the EHG signal. In this paper we describe a procedure which was designed to be applied to short and noisy time series data. This statistical instrument named "approximate entropy" (ApEn), was applied to EHG data analysis. In this study we evaluated the effectiveness of this method for tracking the level of uterine activity in the prelabor period.

Presents a novel pressure sensor that is highly suitable for assessing the variation of uterine activity to prevent preterm labor of high-risk women. The rate of preterm labor is increasing in modern societies and it results in huge medical expenditures. However, preterm labor is hard to perceive in advance because the sensitivity and significance of self-examine is low. The home uterine activity monitoring (HUAM) is a new methodology, which automatically sense the uterine activity and then send the information to physicians or practitioners for further advising or medication. The HUAM can effectively prevent the preterm labor, but the conventional pressure sensors are uncomfortable and expensive. The authors' new design is based on a Colpitts self-oscillating circuit and a ferrite coil. It senses the pressure of uterine contraction by the coil displacement which changes the output frequency. The proposed pressure sensor is light-weighted, stable low-cost, and is appropriate for portable and long-term applications of uterine monitoring.

Introduction Preterm birth is a significant public health and obstetric problem. While accounting for only 6–10% of all births, preterm delivery is responsible for 70–85% of neonatal morbidity and mortality. Approximately three fourths of these preterm births occur secondary to preterm labor or preterm rupture of membranes. Despite the advances in neonatal care and technology, these statistics have not changed dramatically over the last several decades. Obstetricians have approached this issue from preventative and therapeutic standpoints. Preventative measures and methods of identifying women at increased risk for preterm labor have met with limited success. These methods include risk scoring indices, home uterine activity monitoring, ultrasound evaluation of cervical length, serial digital cervical examinations, fetal fibronectin, and salivary estriol testing to name a few. Pharmacologic therapies have been used with the goal of decreasing the morbidity and mortality of prematurity by manipulating the process of parturit ion. This article will focus on the pharmacologic inhibition of labor with an initial overview of the contemporary understanding and approach to preterm labor, goals and criteria for labor inhibition, overview of the mechanisms of parturition and myometrial contractility, followed by a systematic and evidence-based approach to currently used tocolytic agents including betaadrenergic receptor agonists, magnesium sulfate, prostaglandin inhibitors, calcium channel blockers, oxytocin antagonists, and nitric oxide donors.

Clinicians often rely upon the cardiotocogram, a display of the fetal heart rate and maternal uterine activity (UA) over time, as a means of monitoring fetal health during labour. Fetal health can be monitored adequately only when the signal quality of the cardiotocogram is good. We propose an automated assessment of UA signal quality in order to create a confidence index for subsequent analysis of the intrapartum cardiotocogram. We use an autoregressive (AR) model of the UA to estimate the power at the contraction frequency, with high power indicative of "good" UA signal quality. 5th, 10th, and 15th-order AR models are used to assess the signal quality of 12 intrapartum UA traces as "good/medium" or "poor". We compare our results to two experts' visual assessments of signal quality. The 10th-order model exhibits the highest percent agreement rate of 62%. It also exhibits the most balanced false positive and false negative rates, where "good" or "medium" signal quality is considered a positive and "poor" signal quality a negative. The 10th-order model can therefore be used as a confidence index to reduce the errors made in the identification of uterine contractions in the UA trace and in the subsequent analysis of the cardiotocogram as a whole.

Aim To evaluate the feasibility of trans-abdominal fetal ECG (aECG) monitoring with portable device (MONICA AN24) during outpatient labour induction. Methods Low risk post-term women induced with slow release PG E2 pessaries (10 mg) were allowed home for up to 24 h, while aECG, uterine activity and maternal heart rate were continuously monitored. aECG signal was transmitted from the portable device to a hospital PC via ordinary mobile phone (Bluetooth) using Trium CTG Online. aECG traces were displayed in real time on a hospital PC and intermittently reviewed by hospital staff. Women were asked to complete diaries and a subgroup was invited for face to face in depth interview. Results 70 recruited women went home during induction. 17 women stayed at home 10 h. 52 (74%) returned with ruptured membranes/spontaneous labour, 8 (11.4%) recalled for signal loss, 3 (4.2%) with non-reassuring trace and 7 (10%) electively at 24 h. 55 women (79%) had vaginal delivery. 51 diaries were returned. Participants9 location preferences demonstrated that, during induction of labour, women would rather be at home (n=47) than in hospital (n=4). Mean diary ratings indicated that women coped very well at home (n=48); they were very comfortable wearing the device (n=46) and were very satisfied with the outpatient monitoring (n=46). Conclusions Continuous trans-abdominal ECG monitoring of ambulatory women undergoing induction of labour induction at home is feasible and acceptable to women. The quality of remote signal was of sufficient quality to allow clinical decision making in real time.

Oxytocin is the drug most commonly associated with preventable adverse perinatal outcomes. In 2007 it was added to the Institute for Safe Medication Practices short list of medications "bearing a heightened risk of harm," which may "require special safeguards to reduce the risk of error." In January 2009 the American Journal of Obstetrics and Gynecology published a Clinical Opinion paper about oxytocin's inclusion on the list and how the obstetrics profession in the United States should respond. The authors call for the development of specific evidence-based guidelines to reduce the likelihood of patient harm by limiting elective use of oxytocin, decreasing the need for indicated use, reducing dosages during necessary use, giving more responsibility and authority for the patient's safety to the professional who is "at the bedside administering and monitoring the oxytocin infusion" (i.e., the nurse), and accepting that "more time rather than more oxytocin is generally preferable" once adequate uterine activity has been achieved. It is unfortunate that this important paper discounted the risk of harm from cesarean sections and did not mention the strong linkage between epidural analgesia and use of oxytocin. Physicians, midwives, nurses, and others should examine and discuss these issues further in view of increased alertness to the risk of harm from unsafe use of oxytocin.

During oestrous cycles of the camel, spontaneous uterine contractions were correlated significantly with plasma oestradiol-17 beta concentration. Ovariectomy in the camel resulted in a decreased plasma concentration of oestradiol-17 beta (15 pg ml-1) and progesterone (0.1 ng ml-1) and caused complete cessation of uterine activity. Daily administration of oestradiol benzoate (5 mg, intramuscularly) increased the plasma concentration of oestradiol-17 beta (45 pg ml-1) and increased the frequency and amplitude of uterine activity. Coadministration of progesterone (100 mg, intramuscularly) increased the plasma concentration of progesterone (4 ng ml-1) and increased the frequency but not amplitude of uterine activity. It is suggested that uterine activity in the camel is correlated with the circulating levels of oestradiol-17 beta and progesterone.

Twenty-two women > 24 weeks' gestation with a central placenta praevia were monitored to determine if an increase in uterine activity precedes bleeding in patients with central praevias. Monitoring of all subjects began at 26.3 +/- 4.4 weeks and continued until 37 weeks (or delivery if preterm). All subjects had at least one haemorrhage, 7 women had 2, and 4 subjects had 3 episodes of bleeding. Only 3 patients delivered at term while the remainder (86%) delivered preterm. The gestational age at first episode of bleeding was 29.1 +/- 3.6 weeks and at delivery was 34.3 +/- 3.3 weeks. Nine women (41%) had an increase in uterine activity above baseline the day or the day preceding the first haemorrhage. The increase in uterine activity was not statistically significant when compared to the 6 days prior to bleeding when all 22 patients were considered.

Alternative approaches to the management of preterm labor have included home uterine activity monitoring, long-term tocolysis, bed rest, and intravenous hydration. Current evidence in the literature does not support improved pregnancy outcomes with these various therapies.

If we are to develop new strategies for the treatment and management of preterm and dysfunctional term labour, it is imperative that we improve current understanding of the control of human uterine activity. Despite many studies of animal pregnancy, there is a paucity of knowledge relating to the complex control of human myometrium during pregnancy. It is hypothesized that human myometrium is relatively quiescent during the majority of pregnancy and that as term approaches there is cascade of molecular events that prepare the uterus for labour. This review will consider the cellular mechanisms involved in the regulation of human myometrial activity and the modulation of these by hormonal and mechanical signals. In particular, the contribution of calcium homeostatic pathways to the control of human myometrial contractility during gestation will be discussed. Experimental Physiology (2001) 86.2, 247-254.

OBJECTIVE This prospective case series was performed in order to assess pregnancy outcome of women with tentative diagnosis of cervical incompetence undergoing selective and emergency cervical cerclage. METHODS Women recruited in this case series were divided into two groups. The selective group (n = 13) was chosen among pregnant women with a history suggestive of cervical incompetence, but no clinical evidence of threatened miscarriage. The definition of cervical incompetence was dilatation of internal cervical os with shortening of the cervix less than 25 mm and "funnelling" of 25% and more, found on the ultrasound examination of the cervix. The emergency group (n = 12) had clinical symptoms of threatened miscarriage. After exclusion of infection and in the absence of uterine activity they were counseled and offered cerclage. RESULTS After cervical cerclage all women were treated in the same way as per our clinical protocol and monitored until delivery. The median gestational age at delivery was 36 weeks (19-39) in the selective group and 33 weeks (22-38) in the emergency group. This difference is not statistically significant. There was 1 miscarriage (8%), 5 pre-term deliveries (38%) and 7 term deliveries (54%) in the selective group; and 4 miscarriages (33%), 3 pre-term deliveries (25%) and 5 term deliveries (42%) in the emergency group. Total neonatal survival was 19/20 (95%) if pregnancy exceeded 24 weeks, making perinatal mortality 5%. There was no differences between selective and emergency groups (1 of 12 in selective vs. 0 of 8 in emergency). CONCLUSION Overall, it can be concluded that both selective and emergency cerclage may have some benefits in patients with cervical incompetence. However, in the absence of a randomized-controlled study, these beneficial effects described cannot be considered as proved.

Objective: The purpose of this study was to determine if a relationship could be detected between uterine activity and cervical change in the second trimester. Methods: Ten women with evidence of cervical change and 10 women with no cervical change (controls) were studied between 20 and 28 weeks gestation. Uterine activity was recorded using home uterine activity monitoring units. Cervical assessment was performed using transvaginal ultrasound. Results: There was no statistically significant difference in the contractions per hour in the cervical change group (1.26 + 0.38; mean + SEM) compared to the controls (1.13 + 0.48) (p 0.48; Mann-Whitney U test). There were significant differences in closed endocervical length (p < 0.001) and internal os dilatation (p 0.004), the cervical change group demonstrating a shorter closed endocervical length and greater internal os dilatation. Conclusions: This preliminary study shows no evidence of a relationship between uterine activity and endocervical canal length in the second trimester.