Objective
To stratify the risk of spontaneous preterm delivery using cervical length (CL) and fetal fibronectin (fFN) in women with threatened preterm labor who remained pregnant after 7 days.
Design
...Prospective observational study.
Setting
Nationwide cohort of women with threatened preterm labor from the Netherlands.
Population
Women with threatened preterm labor between 24 and 34 weeks with a valid CL and fFN measurement and remaining pregnant 7 days after admission.
Methods
Kaplan–Meier and Cox proportional hazards models were used to estimate cumulative percentages and hazard ratios (HR) for spontaneous delivery.
Main outcome measures
Spontaneous delivery between 7 and 14 days after initial presentation and spontaneous preterm delivery before 34 weeks.
Results
The risk of delivery between 7 and 14 days was significantly increased for women with a CL < 15 mm or a CL ≥15 to <30 mm and a positive fFN, compared with women with a CL ≥30 mm: HR 22.3 95% confidence interval (CI) 2.6–191 and 14 (95% CI 1.8–118), respectively. For spontaneous preterm delivery before 34 weeks the risk was increased for women with a CL < 15 mm HR 6.3 (95% CI 2.6–15) or with a CL ≥15 to <30 mm with either positive fFN HR 3.6 (95% CI 1.5–8.7) or negative fFN HR 3.0 (95% CI 1.2–7.1) compared with women with a CL ≥ 30 mm.
Conclusions
In women remaining pregnant 7 days after threatened preterm labor, CL and fFN results can be used in risk stratification for spontaneous delivery.
Objective: To assess the effect of maintenance tocolysis in women who are at high or low risk for preterm delivery according to fetal fibronectin (fFN) status and cervical length (CL).
Study design: ...We compared the risk of preterm delivery in fFN pos and fFN neg women and in women with a CL <15 mm and ≥15 mm, by using the Cox regression. Differences between the effectiveness of maintenance tocolysis in high- and low-risk women were assessed by using an interaction term.
Results: 122 fFN tests were taken, of which 50 were fFN pos. CL was measured in 236 women, of whom 52 women had a CL <15 mm. The median gestational age at delivery was lower in fFN pos women; fFN pos women had a higher hazard for preterm delivery at any point of time (HR 4.7; 95% CI 2.9 to 7.6). Comparable results were seen for CL. Neither fFN status nor CL did alter the effect of maintenance tocolysis, which was ineffective in the total randomized group, on the risk of preterm delivery (p for interaction = 0.87 for fFN and 0.18 for CL).
Conclusion: Maintenance tocolytic therapy with nifedipine is ineffective and not dependent on fFN or CL status.
Randomized trials on the clinical utility of fetal fibronectin in women with symptoms of preterm labor have thus far failed to demonstrate benefits. We systematically reviewed the methodology of ...these trials to assess if these negative results may be related to their study designs. We searched the literature for randomized trials that evaluated fibronectin testing in women with symptoms of preterm labor. Study results were evaluated and five methodological criteria were assessed: (1) randomization of discordant test results, (2) use of a fixed management protocol, (3) description of interventions in relation to the test result, (4) evaluation of a learning curve, and (5) sample size calculation in agreement with the prevalence of the test results. We detected four randomized trials that met inclusion criteria. All trials allocated women to a strategy with or without availability of fibronectin results without using a discordancy design or a fixed management protocol. One study reported the given treatment in relation to the test results. Learning curves were evaluated in one study. Two studies used transport sample size calculations. The negative results of randomized trials on fetal fibronectin may be due to particular choices in their study design.
A medical tests may influence the health of patients by guiding clinical decisions, such as treatment in case of a positive test result. However, a medical test can influence the health of patients ...through other mechanisms as well, like giving reassurance. To make a clinical recommendation about a medical test, we should be aware of the full range of effects of that test on patients. This requires an understanding of the range of effects that medical testing can have on patients. This study evaluates the mechanisms through which medical testing can influence patients' health, other than the effect on clinical management, from a gynecologist's perspective.
A qualitative study in which explorative focus groups were conducted with gynecologists, gynecological residents and gynecological M.D. researchers (n = 43). Discussions were transcribed verbatim. Transcriptions were coded inductively and analyzed by three researchers.
All participants contributed various clinical examples in which medical testing had influenced patients' health. Clinical examples illustrated that testing, in itself or in interaction with contextual factors, may provoke a wide range of effects on patients. Our data showed that testing can influence the doctor's perceptions of the patients' appraisal of their illness, their perceived control, or the doctor-patient relationship. This may lead to changes in psychological, behavioral, and/or medical outcomes, both favorably or unfavorably. The data were used to construct a conceptual framework of effects of medical testing on patients.
Besides supporting clinical decision making, medical testing may have favorable or unfavorable effects on patients' health though several mechanisms.
Purpose
Transvaginal cervical length measurement in women with symptoms of preterm labor has been used to decide if treatment is necessary. Cervical length measurement may also have additional ...effects on patients, such as providing reassurance, although the evidence to support this is unclear. We explored and summarized to what extent additional effects of cervical length measurement in women with threatened preterm labor have been reported in the clinical literature and what the magnitude of these effects was.
Methods
We performed a systematic review of the literature to identify articles reporting on cervical length measurements in women with symptoms of preterm labor. We assessed whether these articles reported patient outcomes other than preterm delivery.
Results
The electronic and hand search resulted in 764 articles, of which 172 met initial criteria for further eligibility assessment. We found 12 articles that reported additional effects of cervical length measurement in symptomatic women, such as the reassurance or the sensory consequences related to the transvaginal procedure. None of the articles quantified such additional effects.
Conclusions
There appears to be a gap between the presumed effects of cervical length measurement on patient outcomes, such as patients’ reassurance, and the actual assessment of these effects during test evaluations. We suggest that future evaluations of prognostic preterm labor tests include a comprehensive assessment of patient outcomes.
Reply Wilms, Femke F.; Vis, Jolande Y.; Mol, Ben Willem J.
American journal of obstetrics and gynecology,
03/2012, Letnik:
206, Številka:
3
Journal Article
Abstract Objective To compare the accuracy of the Actim Partus test and fetal fibronectin (fFN) test in the prediction of spontaneous preterm delivery within seven days in symptomatic women ...undergoing cervical length measurement. Study Design We performed a post-hoc analysis on frozen samples of a nationwide cohort study in all 10 perinatal centres in the Netherlands. We selected samples from women with signs of preterm labour between 24 and 34 weeks of gestational age and a cervical length below 30 mm. Delivery within seven days after initial assessment was the primary endpoint. We calculated sensitivity, specificity, and positive and negative predictive values for the combination of both the Actim Partus test and fFN test with cervical length. A test was considered positive in case of a cervical length between 15 and 30 mm with a positive Actim Partus or fFN test, and a cervical length below 15 mm regardless the test result. Results In total, samples of 350 women were tested, of whom 69 (20%) delivered within seven days. Eighty-four women had a positive Actim Partus test and 162 women a positive fFN test, of whom 54 (64%) and 63 (39%) delivered within seven days, respectively. Ninety-seven women had a cervical length below 15 mm, of whom 50 (52%) delivered within seven days. Sensitivity, specificity, positive and negative predictive values of combining cervical length with the Actim Partus test or the fFN test were 91%, 75%, 47% and 97%, and 96%, 58%, 36% and 98%, respectively. Conclusion According to this post-hoc study, in combination with cervical length, the Actim Partus test could be used as an alternative for the fFN test to identify women who will not deliver within seven days after presentation. Further evidence should be collected in a prospective comparative study.
To evaluate whether tocolysis with nifedipine can be omitted in women with symptoms of preterm labor, a shortened cervix, and negative fetal fibronectin test.
A randomized noninferiority trial was ...performed in all Dutch perinatal centers. Women with symptoms of preterm labor between 24 and 34 weeks, intact membranes, cervical length between 10 and 30 mm, and negative fibronectin test were randomly allocated to nifedipine (80 mg/day) or placebo. The primary outcome was delivery within 7 days. Secondary outcomes were severe neonatal morbidity and mortality. We also followed all eligible nonrandomized women.
We allocated 37 women to nifedipine and 36 women to placebo. In the nifedipine group, three women (8.1%) delivered within 7 days, compared with one woman (2.8%) in the placebo group (difference -5.3%; one-sided 95% confidence limit 4.5%). Median gestational age at delivery were respectively 37 + 0 (interquartile range IQR 34 + 6 to 38 + 5) and 38 + 2 (IQR 37 + 0 to 39 + 6) weeks (p = 0.008). In the nifedipine group, three pregnancies (8.1%) had a poor outcome; there were no poor outcomes in the placebo group. We observed similar trends in eligible nonrandomized women.
In symptomatic women with preterm labor, a shortened cervix, and negative fibronectin test, placebo treatment is not inferior to tocolysis with nifedipine.
Objective: The objective of this study is to evaluate the relation among fetal gender, ethnicity, and preterm labor (PTL) and preterm delivery (PTD).
Methods: A secondary analysis was performed of a ...prospective cohort study including women with symptoms of PTL between 24 and 34 weeks. The proportion of women carrying a male or female fetus at the onset of PTL was calculated. Gestational age at delivery and risk of PTD of both fetal genders was compared and interaction of fetal gender and maternal ethnicity on the risk of PTD was evaluated.
Results: Of the 594 included women, 327 (55%) carried a male fetus. Median gestational age at delivery in women pregnant with a male fetus was 37 5/7 (IQR 34 4/7-39 1/7) weeks compared with 38 1/7 (IQR 36 0/7-39 5/7) weeks in women pregnant with a female fetus (p = 0.032). The risk of PTD did not differ significantly. In Caucasians, we did find an increased risk of PTD before 37 weeks in women pregnant with a male fetus (OR 1.9 (95% CI 1.2-3.0)).
Conclusions: The majority of women with PTL are pregnant with a male fetus and these women deliver slightly earlier. Race seems to affect this disparity.
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