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American Journal of Obstetrics and... Sep 2022To assess the efficacy and safety of vaginal progesterone to prevent recurrent preterm birth and adverse perinatal outcomes in singleton gestations with a history of... (Meta-Analysis)
Meta-Analysis Review
Does vaginal progesterone prevent recurrent preterm birth in women with a singleton gestation and a history of spontaneous preterm birth? Evidence from a systematic review and meta-analysis.
OBJECTIVE
To assess the efficacy and safety of vaginal progesterone to prevent recurrent preterm birth and adverse perinatal outcomes in singleton gestations with a history of spontaneous preterm birth.
DATA SOURCES
MEDLINE, Embase, LILACS, and CINAHL (from their inception to February 28, 2022), Cochrane databases, Google Scholar, bibliographies, and conference proceedings.
STUDY ELIGIBILITY CRITERIA
Randomized controlled trials that compared vaginal progesterone to placebo or no treatment in asymptomatic women with a singleton gestation and a history of spontaneous preterm birth.
METHODS
The primary outcomes were preterm birth <37 and <34 weeks of gestation. The secondary outcomes included adverse maternal and perinatal outcomes. Pooled relative risks with 95% confidence intervals were calculated. We assessed the risk of bias in the included studies, heterogeneity (I test), small-study effects, publication bias, and quality of evidence; performed subgroup and sensitivity analyses; and calculated 95% prediction intervals and adjusted relative risks.
RESULTS
Ten studies (2958 women) met the inclusion criteria: 7 with a sample size <150 (small studies) and 3 with a sample size >600 (large studies). Among the 7 small studies, 4 were at high risk of bias, 2 were at some concerns of bias, and only 1 was at low risk of bias. All the large studies were at low risk of bias. Vaginal progesterone significantly decreased the risk of preterm birth <37 weeks (relative risk, 0.64; 95% confidence interval, 0.50-0.81; I=75%; 95% prediction interval, 0.31-1.32; very low-quality evidence) and <34 weeks (relative risk, 0.62; 95% confidence interval, 0.42-0.92; I=66%; 95% prediction interval, 0.23-1.68; very low-quality evidence), and the risk of admission to the neonatal intensive care unit (relative risk, 0.53; 95% confidence interval, 0.33-0.85; I=67%; 95% prediction interval, 0.16-1.79; low-quality evidence). There were no significant differences between the vaginal progesterone and the placebo or no treatment groups in other adverse perinatal and maternal outcomes. Subgroup analyses revealed that vaginal progesterone decreased the risk of preterm birth <37 weeks (relative risk, 0.43; 95% confidence interval, 0.33-0.55; I=0%) and <34 weeks (relative risk, 0.27; 95% confidence interval, 0.15-0.49; I=0%) in the small but not in the large studies (relative risk, 0.98; 95% confidence interval, 0.88-1.09; I=0% for preterm birth <37 weeks; and relative risk, 0.94; 95% confidence interval, 0.78-1.13; I=0% for preterm birth <34 weeks). Sensitivity analyses restricted to studies at low risk of bias indicated that vaginal progesterone did not reduce the risk of preterm birth <37 weeks (relative risk, 0.96; 95% confidence interval, 0.84-1.09) and <34 weeks (relative risk, 0.90; 95% confidence interval, 0.71-1.15). There was clear evidence of substantial small-study effects in the meta-analyses of preterm birth <37 and <34 weeks of gestation because of funnel plot asymmetry and the marked differences in the pooled relative risks obtained from fixed-effect and random-effects models. The adjustment for small-study effects resulted in a markedly reduced and nonsignificant effect of vaginal progesterone on preterm birth <37 weeks (relative risk, 0.86; 95% confidence interval, 0.68-1.10) and <34 weeks (relative risk, 0.92; 95% confidence interval, 0.60-1.42).
CONCLUSION
There is no convincing evidence supporting the use of vaginal progesterone to prevent recurrent preterm birth or to improve perinatal outcomes in singleton gestations with a history of spontaneous preterm birth.
Topics: Female; Humans; Infant, Newborn; Intensive Care Units, Neonatal; Pregnancy; Premature Birth; Progesterone; Vagina
PubMed: 35460628
DOI: 10.1016/j.ajog.2022.04.023 -
JAMA Internal Medicine Feb 2022Excessive gestational weight gain (GWG) is common and associated with adverse pregnancy outcomes. Antenatal lifestyle interventions limit GWG; yet benefits of different... (Meta-Analysis)
Meta-Analysis
IMPORTANCE
Excessive gestational weight gain (GWG) is common and associated with adverse pregnancy outcomes. Antenatal lifestyle interventions limit GWG; yet benefits of different intervention types and specific maternal and neonatal outcomes are unclear.
OBJECTIVE
To evaluate the association of different types of diet and physical activity-based antenatal lifestyle interventions with GWG and maternal and neonatal outcomes.
DATA SOURCES
A 2-stage systematic literature search of MEDLINE, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, and Health Technology Assessment Database was conducted from February 1, 2017, to May 31, 2020. Search results from the present study were integrated with those from a previous systematic review from 1990 to February 2017.
STUDY SELECTION
Randomized trials reporting GWG and maternal and neonatal outcomes.
DATA EXTRACTION AND SYNTHESIS
Data were extracted for random-effects meta-analyses to calculate the summary effect estimates and 95% CIs.
MAIN OUTCOMES AND MEASURES
Outcomes were clinically prioritized, with mean GWG as the primary outcome. Secondary outcomes included gestational diabetes, hypertensive disorders of pregnancy, cesarean section, preterm delivery, large or small for gestational age neonates, neonatal intensive care unit admission, or fetal death.
RESULTS
A total of 117 randomized clinical trials of antenatal lifestyle interventions (involving 34 546 women) were included. Overall lifestyle intervention was associated with reduced GWG (-1.15 kg; 95% CI, -1.40 to -0.91), risk of gestational diabetes (odds ratio [OR], 0.79; 95% CI, 0.70-0.89), and total adverse maternal outcomes (OR, 0.89; 95% CI, 0.84-0.94) vs routine care. Compared with routine care, diet was associated with less GWG (-2.63 kg; 95% CI, -3.87 to -1.40) than physical activity (-1.04 kg; 95% CI, -1.33 to -0.74) or mixed interventions (eg, unstructured lifestyle support, written information with weight monitoring, or behavioral support alone) (-0.74 kg; 95% CI, -1.06 to -0.43). Diet was associated with reduced risk of gestational diabetes (OR, 0.61; 95% CI, 0.45-0.82), preterm delivery (OR, 0.43; 95% CI, 0.22-0.84), large for gestational age neonate (OR, 0.19; 95% CI, 0.08-0.47), neonatal intensive care admission (OR, 0.68; 95% CI, 0.48-0.95), and total adverse maternal (OR, 0.75; 95% CI, 0.61-0.92) and neonatal outcomes (OR, 0.44; 95% CI, 0.26-0.72). Physical activity was associated with reduced GWG and reduced risk of gestational diabetes (OR, 0.60; 95% CI, 0.47-0.75), hypertensive disorders (OR, 0.66; 95% CI, 0.48-0.90), cesarean section (OR, 0.85; 95% CI, 0.75-0.95), and total adverse maternal outcomes (OR, 0.78; 95% CI, 0.71-0.86). Diet with physical activity was associated with reduced GWG (-1.35 kg; 95% CI, -1.95 to -0.75) and reduced risk of gestational diabetes (OR, 0.72; 95% CI, 0.54-0.96) and total adverse maternal outcomes (OR, 0.81; 95% CI, 0.69-0.95). Mixed interventions were associated with reduced GWG only.
CONCLUSIONS AND RELEVANCE
This systematic review and meta-analysis found level 1 evidence that antenatal structured diet and physical activity-based lifestyle interventions were associated with reduced GWG and lower risk of adverse maternal and neonatal outcomes. The findings support the implementation of such interventions in routine antenatal care and policy around the world.
Topics: Cesarean Section; Diabetes, Gestational; Diet; Exercise; Female; Gestational Weight Gain; Humans; Hypertension; Infant, Newborn; Male; Pregnancy; Pregnancy Outcome; Premature Birth; Weight Gain
PubMed: 34928300
DOI: 10.1001/jamainternmed.2021.6373 -
American Journal of Perinatology Aug 2017Risk factors for placental abruption have changed, but there has not been an updated systematic review investigating outcomes. We searched PubMed, EMBASE, Web of... (Review)
Review
Risk factors for placental abruption have changed, but there has not been an updated systematic review investigating outcomes. We searched PubMed, EMBASE, Web of Science, SCOPUS, and CINAHL for publications from January 1, 2005 through December 31, 2016. We reviewed English-language publications reporting estimated incidence and/or risk factors for maternal, labor, delivery, and perinatal outcomes associated with abruption. We excluded case studies, conference abstracts, and studies that lacked a referent/comparison group or did not clearly characterize placental abruption. A total of 123 studies were included. Abruption was associated with elevated risk of cesarean delivery, postpartum hemorrhage and transfusion, preterm birth, intrauterine growth restriction or low birth weight, perinatal mortality, and cerebral palsy. Additional maternal outcomes included relaparotomy, hysterectomy, sepsis, amniotic fluid embolism, venous thromboembolism, acute kidney injury, and maternal intensive care unit admission. Additional perinatal outcomes included acidosis, encephalopathy, severe respiratory disorders, necrotizing enterocolitis, acute kidney injury, need for resuscitation, chronic lung disease, infant death, and epilepsy. Few studies examined outcomes beyond the initial birth period, but there is evidence that both mother and child are at risk of additional adverse outcomes. There was also considerable variation in, or absence of, the reporting of abruption definitions.
Topics: Abruptio Placentae; Asphyxia Neonatorum; Blood Transfusion; Cerebral Palsy; Cesarean Section; Female; Fetal Growth Retardation; Humans; Hypoxia, Brain; Infant, Low Birth Weight; Infant, Newborn; Maternal Mortality; Perinatal Mortality; Postpartum Hemorrhage; Pregnancy; Premature Birth; Recurrence; Stillbirth
PubMed: 28329897
DOI: 10.1055/s-0037-1599149 -
JAMA Network Open Jun 2020Knowledge of whether serious adverse pregnancy outcomes are associated with increasingly widespread effects of climate change in the US would be crucial for the...
IMPORTANCE
Knowledge of whether serious adverse pregnancy outcomes are associated with increasingly widespread effects of climate change in the US would be crucial for the obstetrical medical community and for women and families across the country.
OBJECTIVE
To investigate prenatal exposure to fine particulate matter (PM2.5), ozone, and heat, and the association of these factors with preterm birth, low birth weight, and stillbirth.
EVIDENCE REVIEW
This systematic review involved a comprehensive search for primary literature in Cochrane Library, Cochrane Collaboration Registry of Controlled Trials, PubMed, ClinicalTrials.gov website, and MEDLINE. Qualifying primary research studies included human participants in US populations that were published in English between January 1, 2007, and April 30, 2019. Included articles analyzed the associations between air pollutants or heat and obstetrical outcomes. Comparative observational cohort studies and cross-sectional studies with comparators were included, without minimum sample size. Additional articles found through reference review were also considered. Articles analyzing other obstetrical outcomes, non-US populations, and reviews were excluded. Two reviewers independently determined study eligibility. The Arskey and O'Malley scoping review framework was used. Data extraction was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.
FINDINGS
Of the 1851 articles identified, 68 met the inclusion criteria. Overall, 32 798 152 births were analyzed, with a mean (SD) of 565 485 (783 278) births per study. A total of 57 studies (48 of 58 [84%] on air pollutants; 9 of 10 [90%] on heat) showed a significant association of air pollutant and heat exposure with birth outcomes. Positive associations were found across all US geographic regions. Exposure to PM2.5 or ozone was associated with increased risk of preterm birth in 19 of 24 studies (79%) and low birth weight in 25 of 29 studies (86%). The subpopulations at highest risk were persons with asthma and minority groups, especially black mothers. Accurate comparisons of risk were limited by differences in study design, exposure measurement, population demographics, and seasonality.
CONCLUSIONS AND RELEVANCE
This review suggests that increasingly common environmental exposures exacerbated by climate change are significantly associated with serious adverse pregnancy outcomes across the US.
Topics: Air Pollution; Female; Hot Temperature; Humans; Infant, Low Birth Weight; Maternal Exposure; Observational Studies as Topic; Pregnancy; Premature Birth; Stillbirth; United States
PubMed: 32556259
DOI: 10.1001/jamanetworkopen.2020.8243 -
International Journal of Gynaecology... Oct 2022To evaluate the risk levels for maternal and perinatal complications at > 40, > 45 and > 50 years old compared with younger controls. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To evaluate the risk levels for maternal and perinatal complications at > 40, > 45 and > 50 years old compared with younger controls.
METHODS
Electronic databases were searched from their inception until March 2021. We included studies reporting pregnancy outcome in pregnant women aged 40, 45, and 50 years or older compared with controls at the time of delivery. Case reports and case series were excluded. The primary outcome was the incidence of stillbirth. Meta-analysis was performed using the random effects model of DerSimonian and Laird, to produce summary treatment effects in terms of relative risk (RR) with 95% confidence interval (CI). Heterogeneity was measured using I (Higgins I ). Subgroup analyses in women older than 45 years and in those older than 50 years were performed.
RESULTS
Twenty-seven studies, including 31 090 631 women, were included in the meta-analysis. The overall quality of the included studies was moderate to high. Most of the included studies were retrospective cohort studies (21/27), four were population-based studies, and two were cross-sectional studies. Women aged ≥40 years had significantly higher risk of stillbirth (RR 2.16, 95% CI 1.86-2.51), perinatal mortality, intrauterine growth restriction, neonatal death, admission to neonatal intensive care unit, pre-eclampsia, preterm delivery, cesarean delivery, and maternal mortality compared with women younger than 40 years old (RR 3.18, 95% CI 1.68-5.98). The increased risks for maternal mortality were 42.76 and 11.60 for women older than 50 years and for those older than 45 years, respectively, whereas those for stillbirth were 3.72 and 2.32. The risk of stillbirth and cesarean delivery was significantly higher in women >45 years compared with those aged 40-45 years, and in those aged >50 years compared with those aged 45-50 years. The risk of maternal mortality was significantly higher in women aged >50 years compared with those aged 40-45 (RR 60.40, 95% CI 13.28-274.74).
CONCLUSION
The risk of stillbirth, cesarean delivery, and maternal mortality increases with advancing maternal age. The risk ratios for maternal mortality were 3.18, 11.60, and 42.76 in women older than 40, older than 45, and older than 50 years, respectively. These data should be used when women with advanced maternal age are counseled regarding their risk in pregnancy.
SYSTEMATIC REVIEW REGISTRATION
The review was registered with the PROSPERO International Prospective Register of Systematic Reviews (registration No.: CRD42020208788).
Topics: Adult; Female; Humans; Infant, Newborn; Maternal Age; Middle Aged; Perinatal Death; Pregnancy; Pregnancy Outcome; Premature Birth; Retrospective Studies; Stillbirth
PubMed: 35044694
DOI: 10.1002/ijgo.14100 -
The vaginal microbiome and the risk of preterm birth: a systematic review and network meta-analysis.Scientific Reports May 2022Preterm birth is a major cause of neonatal morbidity and mortality worldwide. Increasing evidence links the vaginal microbiome to the risk of spontaneous preterm labour... (Meta-Analysis)
Meta-Analysis
Preterm birth is a major cause of neonatal morbidity and mortality worldwide. Increasing evidence links the vaginal microbiome to the risk of spontaneous preterm labour that leads to preterm birth. The aim of this systematic review and network meta-analysis was to investigate the association between the vaginal microbiome, defined as community state types (CSTs, i.e. dominance of specific lactobacilli spp, or not (low-lactobacilli)), and the risk of preterm birth. Systematic review using PubMed, Web of Science, Embase and Cochrane library was performed. Longitudinal studies using culture-independent methods categorizing the vaginal microbiome in at least three different CSTs to assess the risk of preterm birth were included. A (network) meta-analysis was conducted, presenting pooled odds ratios (OR) and 95% confidence intervals (CI); and weighted proportions and 95% CI. All 17 studies were published between 2014 and 2021 and included 38-539 pregnancies and 8-107 preterm births. Women presenting with "low-lactobacilli" vaginal microbiome were at increased risk (OR 1.69, 95% CI 1.15-2.49) for delivering preterm compared to Lactobacillus crispatus dominant women. Our network meta-analysis supports the microbiome being predictive of preterm birth, where low abundance of lactobacilli is associated with the highest risk, and L. crispatus dominance the lowest.
Topics: Female; Humans; Infant, Newborn; Lactobacillus; Lactobacillus crispatus; Microbiota; Network Meta-Analysis; Pregnancy; Premature Birth; Vagina
PubMed: 35562576
DOI: 10.1038/s41598-022-12007-9 -
Einstein (Sao Paulo, Brazil) 2015Sexual activity during adolescence can lead to unwanted pregnancy, which in turn can result in serious maternal and fetal complications. The present study aimed to... (Review)
Review
Sexual activity during adolescence can lead to unwanted pregnancy, which in turn can result in serious maternal and fetal complications. The present study aimed to evaluate the complications related to adolescent pregnancy, through a systematic review using the Medical Subject Headings: "pregnancy complication" AND "adolescent" OR "pregnancy in adolescence". Only full original articles in English or Portuguese with a clearly described methodology, were included. No qualitative studies, reviews or meta-analyses, editorials, case series, or case reports were included. The sample consisted of 15 articles; in that 10 were cross-sectional and 5 were cohort studies. The overall prevalence of adolescent pregnancy was 10%, and among the Brazilian studies, the adolescent pregnancy rate was 26%. The cesarean delivery rate was lower than that reported in the general population. The main maternal and neonatal complications were hypertensive disorders of pregnancy, prematurity and low birth weight, respectively. Adolescent pregnancy is related to increased frequency of neonatal and maternal complications and lower prevalence of cesarean delivery.
Topics: Adolescent; Brazil; Cohort Studies; Cross-Sectional Studies; Female; Humans; Pregnancy; Pregnancy Complications; Pregnancy Outcome; Pregnancy in Adolescence; Premature Birth; Prevalence; Risk Factors
PubMed: 26061075
DOI: 10.1590/S1679-45082015RW3127 -
American Journal of Obstetrics and... Feb 2018The efficacy of vaginal progesterone for preventing preterm birth and adverse perinatal outcomes in singleton gestations with a short cervix has been questioned after... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The efficacy of vaginal progesterone for preventing preterm birth and adverse perinatal outcomes in singleton gestations with a short cervix has been questioned after publication of the OPPTIMUM study.
OBJECTIVE
To determine whether vaginal progesterone prevents preterm birth and improves perinatal outcomes in asymptomatic women with a singleton gestation and a midtrimester sonographic short cervix.
STUDY DESIGN
We searched MEDLINE, EMBASE, LILACS, and CINAHL (from their inception to September 2017); Cochrane databases; bibliographies; and conference proceedings for randomized controlled trials comparing vaginal progesterone vs placebo/no treatment in women with a singleton gestation and a midtrimester sonographic cervical length ≤25 mm. This was a systematic review and meta-analysis of individual patient data. The primary outcome was preterm birth <33 weeks of gestation. Secondary outcomes included adverse perinatal outcomes and neurodevelopmental and health outcomes at 2 years of age. Individual patient data were analyzed using a 2-stage approach. Pooled relative risks with 95% confidence intervals were calculated. Quality of evidence was assessed using the GRADE methodology.
RESULTS
Data were available from 974 women (498 allocated to vaginal progesterone, 476 allocated to placebo) with a cervical length ≤25 mm participating in 5 high-quality trials. Vaginal progesterone was associated with a significant reduction in the risk of preterm birth <33 weeks of gestation (relative risk, 0.62; 95% confidence interval, 0.47-0.81; P = .0006; high-quality evidence). Moreover, vaginal progesterone significantly decreased the risk of preterm birth <36, <35, <34, <32, <30, and <28 weeks of gestation; spontaneous preterm birth <33 and <34 weeks of gestation; respiratory distress syndrome; composite neonatal morbidity and mortality; birthweight <1500 and <2500 g; and admission to the neonatal intensive care unit (relative risks from 0.47-0.82; high-quality evidence for all). There were 7 (1.4%) neonatal deaths in the vaginal progesterone group and 15 (3.2%) in the placebo group (relative risk, 0.44; 95% confidence interval, 0.18-1.07; P = .07; low-quality evidence). Maternal adverse events, congenital anomalies, and adverse neurodevelopmental and health outcomes at 2 years of age did not differ between groups.
CONCLUSION
Vaginal progesterone decreases the risk of preterm birth and improves perinatal outcomes in singleton gestations with a midtrimester sonographic short cervix, without any demonstrable deleterious effects on childhood neurodevelopment.
Topics: Administration, Intravaginal; Female; Humans; Infant, Newborn; Pregnancy; Pregnancy Outcome; Premature Birth; Progesterone; Progestins; Risk; Treatment Outcome; Uterine Cervical Diseases
PubMed: 29157866
DOI: 10.1016/j.ajog.2017.11.576 -
Advances in Nutrition (Bethesda, Md.) Jul 2019Findings on the relations of maternal dietary patterns during pregnancy and risk of preterm birth and offspring birth size remain inconclusive. We aimed to... (Meta-Analysis)
Meta-Analysis
Findings on the relations of maternal dietary patterns during pregnancy and risk of preterm birth and offspring birth size remain inconclusive. We aimed to systematically review and quantify these associations. We searched MEDLINE, Embase, CENTRAL, and CINAHL up to December 2017. Three authors independently conducted a literature search, study selection, data extraction, and quality assessment. Summary effect sizes were calculated with random effects models and studies were summarized narratively if results could not be pooled. We included 36 studies and pooled results from 25 observational studies (167,507 participants). Two common dietary patterns-"healthy" and "unhealthy"-were identified. Healthy dietary patterns-characterized by high intakes of vegetables, fruits, wholegrains, low-fat dairy, and lean protein foods-were associated with lower risk of preterm birth (OR for top compared with bottom tertile: 0.79; 95% CI: 0.68, 0.91; I2 = 32%) and a weak trend towards a lower risk of small-for-gestational-age (OR: 0.86; 95% CI: 0.73, 1.01; I2 = 34%). Only statistically data-driven healthy dietary patterns, and not dietary index-based patterns, were associated with higher birth weight (mean difference: 67 g; 95% CI: 37, 96 g; I2 = 75%). Unhealthy dietary patterns-characterized by high intakes of refined grains, processed meat, and foods high in saturated fat or sugar-were associated with lower birth weight (mean difference: -40 g; 95% CI: -61, -20 g; I2 = 0%) and a trend towards a higher risk of preterm birth (OR: 1.17; 95% CI: 0.99, 1.39; I2 = 76%). Data from observational studies indicate that greater adherence to healthy dietary patterns during pregnancy is significantly related to lower risk of preterm birth. No consistent associations with birth weight and small- or large-for-gestational-age were observed.
Topics: Adult; Birth Weight; Diet; Diet, Healthy; Feeding Behavior; Female; Gestational Age; Humans; Infant, Low Birth Weight; Infant, Newborn; Maternal Nutritional Physiological Phenomena; Observational Studies as Topic; Pregnancy; Premature Birth; Risk Factors; Young Adult
PubMed: 31041446
DOI: 10.1093/advances/nmy123 -
BMJ (Clinical Research Ed.) Feb 2022To compare the efficacy of bed rest, cervical cerclage (McDonald, Shirodkar, or unspecified type of cerclage), cervical pessary, fish oils or omega fatty acids,... (Comparative Study)
Comparative Study
OBJECTIVES
To compare the efficacy of bed rest, cervical cerclage (McDonald, Shirodkar, or unspecified type of cerclage), cervical pessary, fish oils or omega fatty acids, nutritional supplements (zinc), progesterone (intramuscular, oral, or vaginal), prophylactic antibiotics, prophylactic tocolytics, combinations of interventions, placebo or no treatment (control) to prevent spontaneous preterm birth in women with a singleton pregnancy and a history of spontaneous preterm birth or short cervical length.
DESIGN
Systematic review with bayesian network meta-analysis.
DATA SOURCES
The Cochrane Pregnancy and Childbirth Group's Database of Trials, the Cochrane Central Register of Controlled Trials, Medline, Embase, CINAHL, relevant journals, conference proceedings, and registries of ongoing trials.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
Randomised controlled trials of pregnant women who are at high risk of spontaneous preterm birth because of a history of spontaneous preterm birth or short cervical length. No language or date restrictions were applied.
OUTCOMES
Seven maternal outcomes and 11 fetal outcomes were analysed in line with published core outcomes for preterm birth research. Relative treatment effects (odds ratios and 95% credible intervals) and certainty of evidence are presented for outcomes of preterm birth <34 weeks and perinatal death.
RESULTS
Sixty one trials (17 273 pregnant women) contributed data for the analysis of at least one outcome. For preterm birth <34 weeks (40 trials, 13 310 pregnant women) and with placebo or no treatment as the comparator, vaginal progesterone was associated with fewer women with preterm birth <34 weeks (odds ratio 0.50, 95% credible interval 0.34 to 0.70, high certainty of evidence). Shirodkar cerclage showed the largest effect size (0.06, 0.00 to 0.84), but the certainty of evidence was low. 17OHPC (17α-hydroxyprogesterone caproate; 0.68, 0.43 to 1.02, moderate certainty), vaginal pessary (0.65, 0.39 to 1.08, moderate certainty), and fish oil or omega 3 (0.30, 0.06 to 1.23, moderate certainty) might also reduce preterm birth <34 weeks compared with placebo or no treatment. For the fetal outcome of perinatal death (30 trials, 12 119 pregnant women) and with placebo or no treatment as the comparator, vaginal progesterone was the only treatment that showed clear evidence of benefit for this outcome (0.66, 0.44 to 0.97, moderate certainty). 17OHPC (0.78, 0.50 to 1.21, moderate certainty), McDonald cerclage (0.59, 0.33 to 1.03, moderate certainty), and unspecified cerclage (0.77, 0.53 to 1.11, moderate certainty) might reduce perinatal death rates, but credible intervals could not exclude the possibility of harm. Only progesterone treatments are associated with reduction in neonatal respiratory distress syndrome, neonatal sepsis, necrotising enterocolitis, and admission to neonatal intensive care unit compared with controls.
CONCLUSION
Vaginal progesterone should be considered the preventative treatment of choice for women with singleton pregnancy identified to be at risk of spontaneous preterm birth because of a history of spontaneous preterm birth or short cervical length. Future randomised controlled trials should use vaginal progesterone as a comparator to identify better treatments or combination treatments.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO CRD42020169006.
Topics: Administration, Intravaginal; Bayes Theorem; Female; Humans; Network Meta-Analysis; Pregnancy; Premature Birth; Progesterone; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 35168930
DOI: 10.1136/bmj-2021-064547