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Marc J N C Keirse

Publications and source records attributed to Marc J N C Keirse.

11 recordsLinked to original sources
PubMed2006

Natural prostaglandins for induction of labor and preinduction cervical ripening.

Prostaglandin (PG) E2 has superseded all other natural prostaglandins for induction of labor and pre-induction cervical ripening. This evolution and its rationale are briefly described. PGE2 has been administered intravenously, orally, vaginally, endocervically, and extra-amniotically for induction of labor. All of these, except the intravenous route, have also been explored for pre-induction cervical ripening. The distinction between formal induction and pre-induction is not always clearly made with many studies pursuing both goals at once. Nevertheless, the effectiveness of PGE2 to achieve ripening and induction is currently beyond doubt. In women with unfavorable induction prospects PGE2 results in lower rates of failed induction and higher rates of delivery within a reasonable interval than amniotomy and/or oxytocin. This also applies to women with prelabor rupture of the membranes, but the relative advantages of PGE2 over traditional methods are less clear for women with a favorable cervix. Vaginal administration of PGE2 has superseded virtually all other routes of PGE2 administration except the endocervical route, which tends to give variable results depending on spillage from the endocervical canal. Doses and formulations of vaginal PGE2 with various gels, tablets, pessaries and slow release inserts have varied widely and continue to do so. There is currently no evidence for the superiority of one PGE2 preparation over another.

Cervical Ripening↗
PubMed2006

Does the way that women experience the onset of labour influence the duration of labour?

OBJECTIVE: To assess whether the way in which women experience the onset of their labour influences the duration of their labour. DESIGN: Longitudinal study on a convenient sample of women in spontaneous labour with a singleton pregnancy in cephalic presentation at term. SETTING: University hospital in Germany. POPULATION/SAMPLE: Six hundred and fifty-one women (347 primiparae and 304 parae). METHODS: Women recorded how and when labour had started. Responses were subjected to structured content analysis. Two investigators independently subdivided women's reported signs and symptoms into eight predefined categories. These data were related to maternal characteristics and to the course and outcome of labour as documented in the perinatal record. MAIN OUTCOME MEASURES: Women's perception of how labour had started, interval between onset of labour and rupture of the membranes and duration of first stage labour and overall duration of labour. RESULTS: Only 60% of women reported contractions as a sign of the onset of their labour. These women had a longer interval between the onset of labour and rupture of the membranes but a similar duration of labour when compared with women who did not report contractions as a sign of the onset of labour. Self-reported loss of amniotic fluid was the only sign that showed a consistent relationship with the duration of labour. Other patterns of labour onset had no effect on the duration of labour. CONCLUSION: Irrespective of whether they have given birth before, women experience their onset of labour in a variety of ways. A large proportion of these experiences bear no resemblance to the classical diagnosis of labour and most are unrelated to the duration of labour.

Adult↗
PubMed2005

Influence of fixed and time-dependent factors on duration of normal first stage labor.

BACKGROUND: No accurate method, clinical or otherwise, currently exists to determine the onset of labor precisely. The objective of this study was to investigate what influences the duration of first stage labor in women with spontaneous labor and childbirth in a nonclinical setting. METHODS: From a population-based cohort of 1,448 planned home and birth center births, we selected 932 births for absence of pathology, absence of intervention, and completeness of data. Duration of first stage labor was analyzed with regression analysis for duration data or time-to-event analysis, using a specialized Transition Data Analysis software. The effects of fixed (age, parity, education, antenatal classes, infant birthweight, first cervical assessment) and time-varying factors (start of midwifery care, spontaneous rupture of membranes) in labor were estimated with piecewise-constant exponential hazard models. RESULTS: Of the characteristics immutable at the onset of labor, only parity had a strong effect on the duration of first stage labor. Cervical dilatation at first assessment and time-varying factors, such as the timing of spontaneous rupture of membranes and midwifery care, each had a strong influence on labor duration; however, the sequence in which they occurred exerted an even stronger influence. First stage labors were much shorter if the membranes ruptured before rather than after the start of care. CONCLUSION: With the exception of parity, events occurring during labor and their timing have a greater influence on the duration of first stage spontaneous labor than elements which are immutable at the onset of labor. Trials of interventions to influence the duration of labor need to consider not only whether the intervention was applied or not, but also when it was applied, if cause-effect relationships are to become properly understood.

Adult↗
PubMed2005

An evaluation of pain and "fitness" during labor and its acceptability to women.

BACKGROUND: Labor experiences involve many dimensions that change during labor but are rarely measured contemporaneously and longitudinally. We examined pain and "fitness" aspects of women's labor experience and assessed the acceptability to participants. METHODS: Thirty nulliparas and 20 multiparas in term labor indicated pain and fitness every 45 minutes in contraction-free intervals on visual analog scales from 0 to 10. Fitness implied both physical and psychological strength. Data were analyzed cross-sectionally and longitudinally, with adjustment for analgesia and time dependency. Women received feedback and evaluated their participation on the first day postpartum. RESULTS: Measurements of pain and fitness ranged from 2 to 22 per woman (mean +/- SD: 7.4 +/- 4.4). Pain scores showed various patterns, mostly increasing from 1.4 (+/- 1.9) at the first to 6.6 (+/- 3.8) at the last measurement in nulliparas and from 1.3 (+/- 2.1) to 6.2 (+/- 4.0) in multiparas. One half of the women declined steadily in fitness throughout labor, occasionally after a slight increase early on. Multiparas entered labor more fit (5.9 +/- 3.0) than nulliparas (3.9 +/- 2.7), but showed a sharper decline so that the difference leveled out just before birth. Although fitness at any one time did not reflect pain levels, fitness and pain were inversely related, especially in nulliparas (p = 0.003). Analgesia affected pain scores but affected fitness only a little. Women's responses were mainly positive, especially in appreciating the feedback. Nevertheless, 32 percent of women skipped one or more measurements, often toward the end or when too close to a contraction. CONCLUSIONS: Pain and "fitness" are two distinctly different dimensions of labor experience. Repeated longitudinal measurements of elements of well-being are clearly feasible and acceptable to laboring women. They may be useful to assess how labor events and interventions affect women's well-being.

Cross-Sectional Studies↗
PubMed2004

How many eggs?

Explore the source record for details and available documents.

Female↗
PubMed2004

Perinatal outcome of singletons and twins after assisted conception: a systematic review of controlled studies.

OBJECTIVE: To compare the perinatal outcome of singleton and twin pregnancies between natural and assisted conceptions. DESIGN: Systematic review of controlled studies published 1985-2002. STUDIES REVIEWED: 25 studies were included of which 17 had matched and 8 had non-matched controls. MAIN OUTCOME MEASURES: Very preterm birth, preterm birth, very low birth weight, low birth weight, small for gestational age, caesarean section, admission to neonatal intensive care unit, and perinatal mortality. RESULTS: For singletons, studies with matched controls indicated a relative risk of 3.27 (95% confidence interval 2.03 to 5.28) for very preterm (< 32 weeks) and 2.04 (1.80 to 2.32) for preterm (< 37 weeks) birth in pregnancies after assisted conception. Relative risks were 3.00 (2.07 to 4.36) for very low birth weight (< 1500 g), 1.70 (1.50 to 1.92) for low birth weight (< 2500 g), 1.40 (1.15 to 1.71) for small for gestational age, 1.54 (1.44 to 1.66) for caesarean section, 1.27 (1.16 to 1.40) for admission to a neonatal intensive care unit, and 1.68 (1.11 to 2.55) for perinatal mortality. Results of the non-matched studies were similar. In matched studies of twin gestations, relative risks were 0.95 (0.78 to 1.15) for very preterm birth, 1.07 (1.02 to 1.13) for preterm birth, 0.89 (0.74 to 1.07) for very low birth weight, 1.03 (0.99 to 1.08) for low birth weight, 1.27 (0.97 to 1.65) for small for gestational age, 1.21 (1.11 to 1.32) for caesarean section, 1.05 (1.01 to 1.09) for admission to a neonatal intensive care unit, and 0.58 (0.44 to 0.77) for perinatal mortality. The non-matched studies mostly showed similar trends. CONCLUSIONS: Singleton pregnancies from assisted reproduction have a significantly worse perinatal outcome than non-assisted singleton pregnancies, but this is less so for twin pregnancies. In twin pregnancies, perinatal mortality is about 40% lower after assisted compared with natural conception.

Birth Weight↗
PubMed2004

Progesterone and preterm: seventy years of "déjà vu" or "still to be seen"?

Progestogens for the prevention of preterm birth have a long history. In 2003, two widely publicized double-blind trials, one of daily vaginal progesterone suppositories and the other of weekly intramuscular injections of 17alpha-hydroxyprogesterone, claimed that the treatments effectively reduce the incidence of preterm birth in women at risk of spontaneous preterm labor. Critical analysis of the reports provides no convincing evidence that either one of these treatments is worth pursuing outside the context of controlled research to determine, first, whether and, second, how the treatments might work.

Comment↗
PubMed2003

The history of tocolysis.

In 1950, the World Health Organisation (WHO) defined prematurity as a birthweight of 2500 g or less and in 1961 as a gestational age of less than 37 weeks. The time in between marks an era in which there was growing recognition of the importance of gestational age at birth and how to influence it. The latter was facilitated too by the development of tocography, which permitted some semi-objective measurement of uterine contractility. Along with it, came a growing interest in agents that could control uterine contractility beyond the earlier classical approaches of hormones and gastrointestinal spasmolytics. Hence, the early 1960s saw much research interest in agents, such as nylidrine, isoxsuprine, and orciprenaline that could suppress uterine contractility as one of their many beta-agonist properties. Subsequently, two approaches would be used to shift the balance towards uterine function over and above the influence on other bodily functions. One consisted of supplementing these drugs with agents, such as calcium antagonists and beta-receptor blockers that were hoped to suppress non-uterine actions. The other was a search for drugs in the same class with greater uterospecificity and more selective binding to uterine as opposed to other receptors. Neither of these approaches has ever fully fulfilled the hopes that were pinned on them, but they resulted in the availability of a large number of agents to suppress uterine contractility. The advent of prostaglandins as regulators of uterine contractility and the ability to suppress their biosynthesis saw another range of attempts to suppress uterine activity. They included aspirin, sodium salicylate, flufenamic acid, sulindac and indomethacin, but some were clearly based on a defective understanding of how uterine prostaglandin synthesis can be influenced. In the meantime, a flurry of other agents came and went, often more than once, testifying to the ingenuity of clinicians in trying to solve a problem that is poorly understood. Some, such as relaxin and ethanol, came and disappeared. Others, such as calcium antagonists, entered the scene as protectors against the non-uterine effects of other agents, went, and re-entered the scene in their own right. Still others, such as magnesium sulphate, came, lingered around, and became credited with effects in preterm labour that do not depend on affecting uterine contractility. Amidst this all arose the term tocolysis, coined in 1964 by Mosler from the Greek stems 'tauomicronkappaomicronzeta' and 'lambdaupsilonepsiloniotanu', to epitomise all of this ingenuity.

Female↗
PubMed2002

[The clinical onset of spontaneous labor in obstetrical research].

The onset of labour is a cornerstone in the process of childbirth, albeit difficult to define. When a woman's subjective assessment that labour has started is not accompanied by cervical changes, discrepancies can arise between her and her caregivers' perceptions of what labour and childbirth is all about. In this review we examine how definitions and operational terms for the onset of labour evolved and varied with the prevailing paradigms in the clinical research agenda. In the 1950's, the relatively simple concept of labour, divided in a first stage of dilatation and a second stage of expulsion, changed to encompass a latent and active phase of dilatation, based on the work of Friedman and Sachtleben. Later on, the resulting wide variation in the total duration of labour shrank drastically with the emergence of "active management of labour", which required a different operational definition. Subsequently, the transition from observational to controlled clinical research required firmer starting points. Thus, more readily defined starting points, such as admission to hospital or even time of randomisation, replaced the nebulously vague and erratic "onset of labour" in the clinical research agenda. As the paradigms shifted from labour itself to the outcome of labour, the onset of labour and its vagaries became an embarrassment that needed to be overcome. Yet, within the goal of effective care during labour and childbirth, the onset of labour remains as much of a cornerstone as it has been for a long time. Thence outcome-centred thinking may need to take a step back and also embrace process evaluation, if clinical research in maternity care is to achieve its ultimate aim: optimal care for both mother and baby.

Female↗