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Z Alfirevic

Publications and source records attributed to Z Alfirevic.

At least 19 recordsLinked to original sources
PubMed2001

Postnatal screening for thrombophilia in women with severe pregnancy complications.

OBJECTIVE: To examine the prevalence of maternal thrombophilia in women with severe preeclampsia/eclampsia, placental abruption, fetal growth restriction, and unexplained stillbirth. METHODS: We studied 102 women who had pregnancy complications and 44 healthy women with uncomplicated pregnancies. All women were tested 10 weeks postpartum for mutations of factor V Leiden, methylenetetrahydrofolate reductase (MTHFR) C677T, and G20210A prothrombin gene; deficiencies of protein C, protein S, and antithrombin III; and the presence of lupus anticoagulant and anticardiolipin antibodies. We aimed to recruit 100 cases and 300 controls to detect a 10% difference in thrombophilia between the groups. However, we were able to recruit only 44 controls. RESULTS: Abnormal thrombophilia screen was found in 54 women with pregnancy complications (53%) and in 17 women (39%) with normal pregnancies (odds ratio [OR] 1.8; 95% confidence interval [CI] 0.87, 3.67). Mutations encoding for factor V Leiden, G20210A prothrombin gene, and MTHFR C677T (homozygous) were identified in 18% of women with complications compared with 16% of controls (OR 1.1; 95% CI 0.44, 2.94). Activated protein C resistance, not due to factor V Leiden mutation, was the most common thrombophilic defect, found in 26% of women with pregnancy complications compared with 18% of controls (OR 1.5; 95% CI 0.63, 3.73). Twenty women with complications (20%) had multiple thrombophilic defects compared with four controls (9%) (OR 2.4; 95% CI 0.78, 7.61). CONCLUSION: In our cohort of women with pregnancy complications, maternal thrombophilia was less common than previously thought, and multiple thrombophilias were not a major additional risk factor.

Adolescent↗
PubMed2001

Reducing postnatal pain from perineal tears by using lignocaine gel: a double-blind randomized trial.

BACKGROUND: Perineal pain is one of the most common causes of maternal morbidity in the early puerperium. Several randomized trials have shown that topical application of local anesthetics is effective in reducing postepisiotomy pain, but no randomized study has assessed the efficacy of local anesthetics for other perineal trauma. This study investigated if topically applied 2 percent lignocaine gel was an effective treatment for this group of women. METHODS: A double-blind placebo controlled trial was conducted in a regional teaching hospital in the northwest of England. One hundred and forty-nine women who had sustained a first- or second-degree tear were allocated by sealed envelopes to the lignocaine gel or placebo group. The primary outcome was self-reported pain at 24 hours postdelivery as measured on a numerical rating scale (pain score). Secondary outcomes included pain scores at 48 hours, the need for oral analgesia, and maternal satisfaction. Based on a pilot study, we calculated that 128 women were required to detect a 25 percent difference in pain scores between the two groups with 80 percent power (alpha = 0.05). The pain scores of women in each trial arm were compared using the unpaired t test and 95 percent confidence intervals. RESULTS: Women using lignocaine gel had lower average pain scores, although this only reached statistical significance at 48 hours after delivery (p = 0.023). In general, women liked using the study gel. No difference was found in consumption of oral analgesia. CONCLUSIONS: This study suggested that lignocaine gel may be effective on the second postnatal day. Further research is required to assess the optimum timing of this intervention and the population that would most benefit from its use.

Administration, Topical↗
PubMed2000

Prenatal thyrotropin-releasing hormone for preterm birth.

BACKGROUND: Adding thyrotropin-releasing hormones (TRH) to corticosteroids has been suggested as a way of improving fetal lung development. OBJECTIVES: The objective of this review was to assess the effect of giving prenatal TRH in addition to corticosteroids to women at risk of very preterm birth for the prevention of neonatal respiratory disease. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register, Cochrane Controlled Trials Register, and bibliographies. Date of last search: January 1999. SELECTION CRITERIA: Randomised controlled trials in women at sufficient risk of preterm birth to warrant the use of prenatal corticosteroids to promote lung maturity. TRH and corticosteroids were compared with corticosteroids with or without placebo. The main outcomes considered were fetal and neonatal mortality, neonatal morbidity, childhood development and maternal morbidity. DATA COLLECTION AND ANALYSIS: All assessments of trial eligibility, quality and data extractions were done by at least two authors independently. MAIN RESULTS: Over 4500 women were recruited into the 11 included trials. Five trials were rated of high quality. Overall, prenatal TRH, in addition to corticosteroids, did not reduce the risk of neonatal respiratory disease, chronic oxygen dependance, or improve fetal, neonatal or childhood outcome in any of the outcomes assessed by intention-to-treat analyses. Indeed, the data showed prenatal TRH to have adverse effects for women and their infants. All side effects monitored were more likely to occur in women receiving TRH. In the infants, prenatal TRH increased the risk of infants needing ventilation (relative risk (RR) 1.16, 95% confidence interval (CI) 1.03-1.29), having a low Apgar score at five minutes (RR 1.80, 95% CI 1.14-1.92) and, for the one trial providing data, was associated with poorer outcomes at the 12 month follow up. Sensitivity analyses by trial quality, or subgroups with differing times from entry to delivery, or different dose regimens of TRH, did not change these findings. REVIEWER'S CONCLUSIONS: On the basis of currently available evidence, prenatal TRH, in addition to corticosteroids, given to women at risk of very preterm birth cannot be recommended for clinical practice.

Female↗
PubMed2000

Biophysical profile for fetal assessment in high risk pregnancies.

BACKGROUND: Biophysical profile usually includes ultrasound monitoring of fetal movements, fetal tone and fetal breathing, ultrasound assessment of amniotic fluid volume and assessment of fetal heart rate by electronic monitoring. OBJECTIVES: The objective of this review was to assess the effects of biophysical profile tests on pregnancy outcome in high risk pregnancies. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth trials register. Date of last search: October 1998. SELECTION CRITERIA: Randomised trials comparing fetal biophysical profile with other forms of fetal assessment in women with high risk pregnancies. DATA COLLECTION AND ANALYSIS: Trial quality was assessed. MAIN RESULTS: Four studies were included. Most trials were not of high quality. No difference was found between biophysical profile and other forms of fetal assessment over a range of fetal and neonatal measures. REVIEWER'S CONCLUSIONS: At present, there is not enough evidence from randomised trials to evaluate the use of biophysical profile as a test of fetal well-being in high risk pregnancies.

Embryonic and Fetal Development↗
PubMed2000

Chorion villus sampling versus amniocentesis for prenatal diagnosis.

BACKGROUND: Amniocentesis test results are usually available only after 18 weeks gestation. Chorion villus sampling (CVS) may be performed transabdominally or transvaginally, usually between 10 and 12 weeks gestation. OBJECTIVES: The objective of this review was to assess the safety and accuracy of chorion villus sampling compared to amniocentesis. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. SELECTION CRITERIA: Randomised trials comparing first trimester chorion villus sampling and second trimester amniocentesis. DATA COLLECTION AND ANALYSIS: Trial quality was assessed. MAIN RESULTS: Three studies involving over 9000 women were included. The trials were generally of good quality. Compared to amniocentesis, chorion villus sampling was associated with more sampling and technical failures, and more false positive and false negative results. Pregnancy loss was more common after chorion villus sampling (odds ratio 1.33, 95% confidence interval 1.17 to 1.52). There is a suggestion (though not statistically significant) of an increase in stillbirths and neonatal deaths following chorion villus sampling. Maternal complications were uncommon. REVIEWER'S CONCLUSIONS: The increase in miscarriages after chorion villus sampling compared to amniocentesis appear to be procedure related. Second trimester amniocentesis appears to be safer than chorion villus sampling. The benefits of earlier diagnosis with chorion villus sampling must be set against the greater risk of pregnancy loss.

Chorionic Villi Sampling↗
PubMed2000

Doppler ultrasound for fetal assessment in high risk pregnancies.

BACKGROUND: Abnormal waveforms from Doppler ultrasound may indicate poor fetal prognosis. It is also possible that Doppler ultrasound could encourage inappropriate early delivery. OBJECTIVES: The objective of this review was to assess the effects of Doppler ultrasound in high risk pregnancies on obstetric care and fetal outcomes. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register. SELECTION CRITERIA: Randomised trials of Doppler ultrasound for the investigation of umbilical artery waveforms in high risk pregnancies compared to no Doppler ultrasound. DATA COLLECTION AND ANALYSIS: Trial quality was assessed and data were extracted by both reviewers. Study authors were contacted for additional information. MAIN RESULTS: Eleven studies involving nearly 7000 women were included. The trials were generally of good quality. Compared to no Doppler ultrasound, Doppler ultrasound in high risk pregnancy (especially those complicated by hypertension or presumed impaired fetal growth) was associated with a trend to a reduction in perinatal deaths (odds ratio 0.71, 95% confidence interval 0.50 to 1.01). The use of Doppler ultrasound was also associated with fewer inductions of labour (odds ratio 0.83, 95% confidence interval 0.74 to 0.93) and fewer admissions to hospital (odds ratio 0.56, 95% 0.43 to 0.72), without reports of adverse effects. No difference was found for fetal distress in labour (odds ratio 0.81, 95% confidence interval 0.59 to 1.13) or caesarean delivery (odds ratio 0.94, 95% 0.82 to 1.06). REVIEWER'S CONCLUSIONS: The use of Doppler ultrasound in high risk pregnancies appears to improve a number of obstetric care outcomes and appears promising in helping to reducing perinatal deaths.

Blood Flow Velocity↗
PubMed2000

Early amniocentesis versus transabdominal chorion villus sampling for prenatal diagnosis.

BACKGROUND: A major disadvantage of amniocentesis is that test results are usually available only after 18 weeks gestation. Early amniocentesis can now be done between 9 to 14 weeks gestation. OBJECTIVES: The objective was to assess the safety and accuracy of early amniocentesis compared with chorion villus sampling. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register were searched. Date of last search: October 1998. SELECTION CRITERIA: Randomised trials comparing early amniocentesis with transabdominal chorion villus sampling. DATA COLLECTION AND ANALYSIS: One reviewer assessed eligibility and trial quality. MAIN RESULTS: Three studies were included. Sampling failure was 0.4% in the early amniocentesis group compared to 2% in the chorion villus group (relative risk 0.23, 95% confidence interval 0.08 to 0.65). Consequently, more women in the chorion villus sampling group needed a second prenatal diagnostic test (relative risk 0.43, 95% confidence interval 0.21 to 0.88). There were no statistically significant differences in the laboratory failures (relative risk 0.43, 95% confidence interval 0. 17 to 1.10) or number of women with various chromosomal abnormalities (relative risk 0.51, 95% confidence interval 0.26 to 1. 04). Combined total pregnancy loss in the early amniocentesis group was 6.2% (57/915) compared with 5% (46/917) in the chorion villus sampling group (relative risk 1.24, 95% confidence interval 0.85 to 1.81). There were more spontaneous miscarriages after early amniocentesis (4.4% versus 2.3%, relative risk 1.92, 95% confidence interval 1.14 to 3.23). There was no difference in the incidence of neonatal respiratory distress and anomalies in the newborn infants. The incidence of talipes was greater in the early amniocentesis group, although haemangiomas were more common in the chorion villus sampling group. REVIEWER'S CONCLUSIONS: Current data suggest that early amniocentesis is associated with a greater risk of spontaneous miscarriage and neonatal talipes compared to transabdominal chorion villus sampling. An increased risk of these complications needs to be weighed against fewer technical difficulties and the possibility of fewer neonatal haemangiomas.

Amniocentesis↗
PubMed2000

Instruments for transcervical chorionic villus sampling for prenatal diagnosis.

BACKGROUND: The type of instrument used in chorion villus sampling could have a significant impact on the success rate of the procedure. An ability to manoeuvre the instrument within the uterine cavity without puncturing the gestational sac, and to see the tip of the instrument on ultrasound scanning are particularly important. OBJECTIVES: The objective of this review was to assess the effects of different instruments for transcervical chorionic villus sampling on perinatal outcome, quality and quantity of obtained tissue, technical difficulties during the procedure and maternal adverse effects. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register was searched. Date of last search: October 1998. SELECTION CRITERIA: Randomised trials comparing different instruments for transcervical chorionic villus sampling. DATA COLLECTION AND ANALYSIS: Eligibility and trial quality were assessed by one reviewer. MAIN RESULTS: Three trials involving 268 women were included. None of the trials mentioned method of randomisation. An adequate sample was more likely to be obtained using small forceps than aspiration cannula (odds ratio 7.29, 95% confidence interval 3. 39 to 15.67). However small forceps were more difficult to insert than an aspiration cannula (odds ratio 0.35, 95% confidence interval 0.13 to 0.96). Use of the Portex cannula was more likely to result in an inadequate sample and a difficult or painful procedure when compared with either the silver or aluminium cannula respectively. REVIEWER'S CONCLUSIONS: Although there is some evidence to support the use of small forceps for transcervical chorionic villus sampling, it is not strong enough to support change in practice for clinicians who have become familiar with aspiration cannulas.

Chorionic Villi Sampling↗
PubMed2000

Oral misoprostol for induction of labour with a viable fetus.

BACKGROUND: Misoprostol is a synthetic prostaglandin which has been used to induce labour. Oral use of the drug misoprostol may be convenient, but an overdose could cause uterine hyperstimulation and precipitate labour which may be life-threatening for both mother and fetus. OBJECTIVES: The objective of this review was to assess the effects of oral misoprostol used for labour induction in women with a viable fetus. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. SELECTION CRITERIA: Randomised trials of oral misoprostol versus any other method, placebo or no treatment given to women with a viable fetus for induction of labour. DATA COLLECTION AND ANALYSIS: The selection of trials and data extraction were undertaken by one reviewer and independently checked by two other reviewers. MAIN RESULTS: Five trials were included. In one placebo trial, oral misoprostol reduced the need for oxytocin infusion and shortened delivery time in women with prelabour rupture of membranes at term. In another trial, compared to vaginal prostaglandins, oral misoprostol reduced the need for oxytocin (relative risk 0.62, 95% confidence interval 0.47 to 0.82). Based on two trials, the caesarean section rate with oral misoprostol was 20. 2% (55/272) compared with 15.5% (42/270) for vaginal prostaglandins (relative risk 1.29, 95% confidence interval 0.90 to 1.86). Different doses (100 micrograms three hourly and 200 micrograms six hourly) were used in the two trials that compared oral with vaginal misoprostol. The caesarean section rate was 21.8% in the oral misoprostol group compared with 13.5% for vaginal misoprostol (relative risk 1.62, 95% confidence interval 0.85 to 3.09). The uterine hyperstimulation rate with oral misoprostol was 37.5% (36/96) compared with 28% (25/89) for vaginal misoprostol (relative risk 1.32, 95% confidence interval 0.86 to 2.04). There was significant heterogeneity between these two trials. REVIEWER'S CONCLUSIONS: Oral misoprostol may be an effective method for labour induction. However clinically effective oral regimens may have an unacceptably high incidence of uterine hyperstimulation and possibly uterine rupture.

Female↗
PubMed1999

Misoprostol for induction of labour: a systematic review.

OBJECTIVE: To determine, from the best available evidence, the effectiveness and safety of misoprostol administered vaginally or orally for third trimester cervical ripening or induction of labour. METHODS: Clinical trials of misoprostol used for cervical ripening or labour induction in the third trimester were identified from the register of randomised trials maintained by the Cochrane Pregnancy and Childbirth Group. All identified trials were considered for inclusion in the review according to a prespecified protocol. Primary outcomes were chosen to address clinical effectiveness (delivery within 24 hours) and safety (uterine hyperstimulation, caesarean section, serious maternal and neonatal morbidity) and were determined a priori. All meta-analyses were based on the intention-to-treat principle. In the absence of heterogeneity the summary statistics have been expressed as typical relative risk (RR) and 95% confidence interval (CI). RESULTS: Vaginal misoprostol: one small study showed that the use of misoprostol results in more effective cervical ripening and reduced need for oxytocin when compared with placebo. When compared with oxytocin, vaginal misoprostol was more effective for labour induction. The relative risk of failure to achieve vaginal delivery within 24 hours was 0.48 (95% CI 0.35 to 0.66). However, the relative risks for uterine hyperstimulation with and without fetal heart rate abnormalities were 2.54 (95% CI 1.12 to 5.77) and 2.96 (95% CI 2.11 to 4.14), respectively. In three out of four trials which studied women with intact membranes and unfavourable cervices, failure to achieve vaginal delivery within 24 hours was reduced with misoprostol when compared with other prostaglandins (RR 0.71, 95% CI 0.62 to 0.81). Vaginal misoprostol was associated with increased uterine hyperstimulation both without fetal heart rate changes (RR 1.67, 95% CI 1.30 to 2.14) and with associated fetal heart rate changes (RR 1.45, 95% CI 1.04 to 2.04). There was also an increase in meconium stained amniotic fluid following vaginal misoprostol (RR 1.38, 95% CI 1.06 to 1.79). Oral misoprostol: one small trial suggests that, when compared with placebo, oral misoprostol reduces the need for oxytocin and shortens the time between induction and delivery. Compared with other prostaglandins one small trial showed a reduced need for oxytocin with oral misoprostol. Two trials compared oral with vaginal misoprostol using different doses. No significant differences were evident. CONCLUSIONS: Overall, misoprostol appears to be more effective than conventional methods of cervical ripening and labour induction. Although no differences in perinatal outcome were shown, the studies were not sufficiently large to exclude the possibility of uncommon serious adverse effects. In particular the increase in uterine hyperstimulation with fetal heart rate changes following misoprostol is a matter for concern. It is possible that, if sufficient numbers are studied, an unacceptably high number of serious adverse events including uterine rupture and asphyxial fetal deaths may occur. The data at present are not robust enough to address the issue of safety. Thus, though misoprostol shows promise as a highly effective, inexpensive and convenient agent for labour induction, it cannot be recommended for routine use at this stage. Lower dose misoprostol regimens should be investigated further.

Administration, Intravaginal↗
PubMed1999

Two trials of antenatal thyrotrophin-releasing hormone for fetal maturation: stopping before the due date. Antenatal TRH Trial and the Thyroneth Trial Groups.

OBJECTIVES: To determine whether the addition of antenatal thyrotrophin-releasing hormone (TRH) to corticosteroids, given to women at risk of preterm delivery, would decrease the risk of death and severe morbidity associated with prematurity. DESIGN: Two concurrent multicentre, double blind, randomised, placebo-controlled trials were designed with a common core dataset to be analysed as a single large pragmatic trial. SETTING: Hospital maternity units. POPULATIONS: Pregnant women at risk of preterm delivery who had been prescribed a course of corticosteroids to enhance fetal maturation. INTERVENTIONS: Antenatal administration of TRH 400 microg every eight hours for four doses versus matching placebo. MAIN OUTCOME MEASURES: Primary: death of the baby or chronic lung disease (defined as oxygen dependency at 28 days after birth). Secondary: other measures of respiratory morbidity, in particular respiratory distress syndrome. Other measures of short term neonatal morbidity including intraventricular haemorrhage and necrotising enterocolitis. Measures of maternal side effects. RESULTS: The antenatal TRH trial was halted early on the basis of external evidence. Overall a total of 225 women were recruited who delivered 275 babies. The primary outcome of death or chronic lung disease occurred in 33 babies in the TRH group and 43 babies in the placebo group (RR 0.8, 95% CI 0.5-1.2). There were no other differences between the two groups. Stratified analysis did not reveal any differences between the two groups depending on how long before the time of delivery the mother had received the TRH or placebo. CONCLUSIONS: These trials are too small to provide convincing evidence of the effect of antenatal TRH on neonatal outcome. When added to the existing systematic review and meta-analysis, however, these data should provide evidence on which subsequent practice can be based. The process by which the trials were monitored and stopped is of relevance to future trials.

Adrenal Cortex Hormones↗
PubMed1999

Are we prescribing multiple courses of antenatal corticosteroids? A survey of practice in the UK.

A postal questionnaire concerned with prescribing antenatal corticosteroids was sent to one named clinician at each of 279 obstetric units in the UK. They were asked whether their unit prescribed repeated courses, the indications for which these would be prescribed, the interval between courses, the drugs and regimens used and whether they would be willing to participate in a proposed randomised controlled trial. The response rate was 75%. Of the respondents, 98% prescribed repeated courses; the indications most commonly cited by units who prescribed steroids were prelabour spontaneous rupture of membranes (84.2%) and suspected preterm labour (81.8%). 70.6% of units were willing to participate in the proposed trial.

Adrenal Cortex Hormones↗
PubMed1999

External cephalic version.

The management of breech presentation at term is variable. This article presents the options, and reviews the current evidence for, and success rate of, external cephalic version. The work of the breech clinic at the Liverpool Women's Hospital is also discussed.

Algorithms↗