Exercise during pregnancy and risk of gestational hypertensive disorders: a systematic review and meta-analysis

How to promote physical activity during pregnancy : A systematic review

INTRODUCTION

Sedentary lifestyles and physical inactivity have been shown to increase during pregnancy and are a cause of obstetric comorbidity. The objective of this study was to conduct a systematic review of interventions aiming to promote physical activity during pregnancy.

MATERIAL AND METHODS

Databases were searched from January 2008 to September 2019. Selection criteria included randomized controlled trials evaluating the efficacy of interventions promoting physical activity during pregnancy.

RESULTS

In total, 256 articles were extracted from databases. 202 articles were excluded. Finally, 15 articles were included in the study. 5633 patients were included from various populations. Six studies rated physical activity (PA) as the primary outcome. Five studies suggested promoting physical activity through individual interviews which in two studies showed an increase in PA. Three studies evaluated an intervention based on group interviews and one of these reported a significant increase in PA. Two studies evaluated the use of a Smartphone application to promote physical activity but they did not conclude that they were effective because they were designed with low statistical power.

CONCLUSION

The practice of regular PA during pregnancy reduces obstetrical comorbidity. However, interventions seem to have a low impact on the promotion of PA during pregnancy. New intervention strategies need to assessed, such as the use of mobile health interventions.

The Effect of Exercise Training During Pregnancy to Improve Maternal Vascular Health: Focus on Gestational Hypertensive Disorders

Hypertensive disorders of pregnancy, including gestational hypertension and pre-eclampsia, occur in up to 10% of pregnancies and are associated with increased life-long cardiovascular risk. Physical activity improves cardiovascular health in pregnancy and may lower the risk of developing hypertensive disorders of pregnancy. However, a minority of pregnant women comply with the recommended level of physical activity. Adequate knowledge on the physiological effects of exercise in healthy pregnancy could help to overcome potential barriers as pregnancy is a unique window of opportunity to improve health outcomes for both mother and child. In this mini review, we discuss structural and functional vascular adaptations during healthy and hypertensive pregnancies, we elaborate on the effects of exercise on the vasculature and review the safety and existing evidence of exercise training as preventive therapy for gestational hypertensive disorders.

Physical activity, sedentary behavior and development of preeclampsia in women with preexisting diabetes

AIMS

To explore the association between physical activity in early pregnancy and development of preeclampsia in women with preexisting diabetes.

METHODS

In a prospective cohort study of 189 women with preexisting diabetes (110 type 1 and 79 type 2 diabetes), physical activity during pregnancy including sedentary behavior was evaluated with the Pregnancy Physical Activity Questionnaire. Primary outcome was preeclampsia. Secondary outcomes were preterm delivery, large and small for gestational age infants.

RESULTS

Women developing preeclampsia (n = 23) had higher diastolic blood pressure in early pregnancy (mean 82 ± 9 SD vs. 77 ± 8, p = 0.004) and were more often nulliparous (91 vs. 52%, p < 0.001) compared with the remaining women (n = 166). Total physical activity in early pregnancy was similar between the groups (median 148 metabolic equivalent of task hours per week (MET-h/week) (interquartile range 118-227) versus 153 (121-205), p = 0.97). In early pregnancy, women developing preeclampsia reported a higher level of sedentary behavior (15 MET-h/week (7-18) versus 7 (4-15); p = 0.04); however, when adjusting for parity, diastolic blood pressure and smoking, the association attenuated (p = 0.13). Total physical activity and sedentary behavior in early pregnancy were not associated with preterm delivery, large or small for gestational age infants.

CONCLUSIONS

Among women with diabetes, sedentary behavior was reported higher in early pregnancy in women developing preeclampsia compared with the remaining women, while total physical activity was similar. Sedentary behavior was a predictor of preeclampsia in the univariate analysis, but not in the multiple regression analysis, and larger studies are needed to evaluate this possible modifiable risk factor. Trial registration The study was registered at ClinicalTrials.gov (ID: NCT02890836).

Physical Activity and Exercise During Pregnancy and the Postpartum Period: ACOG Committee Opinion, Number 804

Exercise, defined as physical activity consisting of planned, structured, and repetitive bodily movements done to improve one or more components of physical fitness, is an essential element of a healthy lifestyle, and obstetrician-gynecologists and other obstetric care providers should encourage their patients to continue or to commence exercise as an important component of optimal health. Women who habitually engaged in vigorous-intensity aerobic activity or who were physically active before pregnancy can continue these activities during pregnancy and the postpartum period. Observational studies of women who exercise during pregnancy have shown benefits such as decreased gestational diabetes mellitus, cesarean birth and operative vaginal delivery, and postpartum recovery time. Physical activity also can be an essential factor in the prevention of depressive disorders of women in the postpartum period. Physical activity and exercise in pregnancy are associated with minimal risks and have been shown to benefit most women, although some modification to exercise routines may be necessary because of normal anatomic and physiologic changes and fetal requirements. In the absence of obstetric or medical complications or contraindications, physical activity in pregnancy is safe and desirable, and pregnant women should be encouraged to continue or to initiate safe physical activities. This document has been revised to incorporate recent evidence regarding the benefits and risks of physical activity and exercise during pregnancy and the postpartum period.

Experiences of participation in supervised group exercise among pregnant women with depression or low psychological well-being: A qualitative descriptive study

OBJECTIVE

To explore experiences with supervised group exercise during pregnancy in women with depression or low psychological well-being.

DESIGN

A qualitative descriptive study based on semi-structured, individual, in-depth interviews analyzed by means of thematic analysis.

SETTING

The Department of Obstetrics, Rigshospitalet, Copenhagen University Hospital, Denmark.

PARTICIPANTS

Through a purposeful, criterion-based sampling strategy, women with a current diagnosis of depression with prescribed antidepressant and/or a score ≤50 on the five-item World Health Organization Well-being Index were included. The women were recruited from a randomized controlled trial on the effects of supervised group exercise (the EWE study) and participated in the exercise program during the period 26 January 2017-8 March 2018. A total of 282 pregnant women participated in the RCT, of which 143 women were allocated to the intervention group. Of these, 27 women were eligible and were invited; 19 accepted the invitation and were included in the current qualitative descriptive study. Diversity of age, parity, level of education and employment status was seen in the sample. The average time from completing the exercise program to conducting the interview was 6.5 months, ranging from 1 week to 13 months.

INTERVENTION

The participants were offered an in-hospital supervised group exercise program twice weekly for 12 weeks from 17-22 weeks gestation in addition to standard antenatal care.

MEASUREMENTS AND FINDINGS

Qualitative thematic analysis of the interviews resulted in the identification of the overarching theme: Vulnerable yet strong. This theme was comprised from three main themes (1) From judging the body to feeling it, (2) A "we" is created, and (3) Taking responsibility and succeeding, together with nine sub-themes.

KEY CONCLUSIONS

The supervised group exercise intervention provided experiences of peer support and increased body awareness, which contributed to an experience of improved psychological equilibrium and preparedness for the coming birth and motherhood. The findings suggest that participation in group-based supervised exercise during pregnancy in women with depression or low psychological well-being contributes to psychological resilience, which may persist as a positive influence postpartum and beyond.

IMPLICATIONS FOR PRACTICE

In-hospital supervised group-based exercise can be a safe means to health promotion in a secure environment that supports pregnant women's physical and mental well-being while also preparing them for birth and the transition to motherhood.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Epigenetic biomarkers and preterm birth

Preterm birth (PTB) is a major public health challenge, and novel, sensitive approaches to predict PTB are still evolving. Epigenomic markers are being explored as biomarkers of PTB because of their molecular stability compared to gene expression. This approach is also relatively new compared to gene-based diagnostics, which relies on mutations or single nucleotide polymorphisms. The fundamental principle of epigenome diagnostics is that epigenetic reprogramming in the target tissue (e.g. placental tissue) might be captured by more accessible surrogate tissue (e.g. blood) using biochemical epigenome assays on circulating DNA that incorporate methylation, histone modifications, nucleosome positioning, and/or chromatin accessibility. Epigenomic-based biomarkers may hold great potential for early identification of the majority of PTBs that are not associated with genetic variants or mutations. In this review, we discuss recent advances made in the development of epigenome assays focusing on its potential exploration for association and prediction of PTB. We also summarize population-level cohort studies conducted in the USA and globally that provide opportunities for genetic and epigenetic marker development for PTB. In addition, we summarize publicly available epigenome resources and published PTB studies. We particularly focus on ongoing genome-wide DNA methylation and epigenome-wide association studies. Finally, we review the limitations of current research, the importance of establishing a comprehensive biobank, and possible directions for future studies in identifying effective epigenome biomarkers to enhance health outcomes for pregnant women at risk of PTB and their infants.

Postpartum Interventions to Reduce Long-Term Cardiovascular Disease Risk in Women After Hypertensive Disorders of Pregnancy: A Systematic Review

Introduction: Hypertensive disorders (HDP) affect ~7% of pregnancies. Epidemiological evidence strongly suggests HDP independently increases that individual's risk of later cardiovascular disease (CVD). Focus on reduction or mitigation of this risk has been limited. This review seeks to identify trialed interventions to reduce cardiovascular risk after HDP. Methods: Online medical databases were searched to identify full-text published results of randomized controlled trials (RCT) in women <10 years postpartum after HDP that trialed interventions to reduce cardiovascular risk. Outcomes sought included cardiovascular disease events, chronic hypertension, and other measures of cardiovascular risk such as obesity, smoking status, diet, and physical activity. Publications from January 2008 to July 2019 were included. Results: Two RCTs were identified. One, a trial of calcium vs. placebo in 201 women with calcium commenced from the first follow-up visit outside of pregnancy and continued until 20 weeks' gestation if another pregnancy occurred. A non-significant trend toward decreased blood pressure was noted. The second RCT of 151 women tested an online education programme (vs. general information to control group) to increase awareness of risk factors and personalized phone-based lifestyle coaching in women who had a preeclampsia affected pregnancy in the 5 years preceding enrolment. Significant findings included increase in knowledge of CVD risk factors, reported healthy eating and decreased physical inactivity, however adoption of a promoted heart healthy diet and physical activity levels did not differ significantly between groups. Several observational studies after HDP, and one meta-analysis of studies of lifestyle interventions not performed specifically after HDP but used to extrapolate likely benefits of lifestyle interventions, were identified which supported the use of lifestyle interventions. Several ongoing RCTs were also noted. Discussion: There is a paucity of intervention trials in the early years after HDP to guide evidence-based cardiovascular risk reduction in affected women. Limited evidence suggests lifestyle intervention may be effective, however degree of any risk reduction remains uncertain. Conclusion: Sufficiently powered randomized controlled trials of appropriate interventions (e.g., lifestyle behavior change, pharmacological) are required to assess the best method of reducing the risk of cardiovascular disease in this at-risk population of women.

Maternal physical activity prevents the overexpression of hypoxia-inducible factor 1-α and cardiorespiratory dysfunction in protein malnourished rats

Maternal physical activity attenuates cardiorespiratory dysfunctions and transcriptional alterations presented by the carotid body (CB) of rats. Rats performed physical activity and were classified as inactive/active. During gestation and lactation, mothers received either normoprotein (NP-17% protein) or low-protein diet (LP-8% protein). In offspring, biochemical serum levels, respiratory parameters, cardiovascular parameters and the mRNA expression of hypoxia-inducible factor 1-alpha (HIF-1α), tyrosine hydroxylase (TH) and purinergic receptors were evaluate. LP-inactive pups presented lower RF from 1^st to 14^th days old, and higher RF at 30 days than did NP-inactive and NP-active pups. LP-inactive pups presented with reduced serum protein, albumin, cholesterol and triglycerides levels and an increased fasting glucose level compared to those of NP-inactive and NP-active groups. LP and LP-inactive animals showed an increase in the cardiac variability at the Low-Frequency bands, suggesting a major influence of sympathetic nervous activity. In mRNA analyses, LP-inactive animals showed increased HIF-1α expression and similar expression of TH and purinergic receptors in the CB compared to those of NP groups. All these changes observed in LP-inactive pups were reversed in the pups of active mothers (LP-active). Maternal physical activity is able to attenuate the metabolic, cardiorespiratory and HIF-1α transcription changes induced by protein malnutrition.

Preeclampsia: Risk Factors, Diagnosis, Management, and the Cardiovascular Impact on the Offspring

Hypertensive disorders of pregnancy affect up to 10% of pregnancies worldwide, which includes the 3%–5% of all pregnancies complicated by preeclampsia. Preeclampsia is defined as new onset hypertension after 20 weeks’ gestation with evidence of maternal organ or uteroplacental dysfunction or proteinuria. Despite its prevalence, the risk factors that have been identified lack accuracy in predicting its onset and preventative therapies only moderately reduce a woman’s risk of preeclampsia. Preeclampsia is a major cause of maternal morbidity and is associated with adverse foetal outcomes including intra-uterine growth restriction, preterm birth, placental abruption, foetal distress, and foetal death in utero. At present, national guidelines for foetal surveillance in preeclamptic pregnancies are inconsistent, due to a lack of evidence detailing the most appropriate assessment modalities as well as the timing and frequency at which assessments should be conducted. Current management of the foetus in preeclampsia involves timely delivery and prevention of adverse effects of prematurity with antenatal corticosteroids and/or magnesium sulphate depending on gestation. Alongside the risks to the foetus during pregnancy, there is also growing evidence that preeclampsia has long-term adverse effects on the offspring. In particular, preeclampsia has been associated with cardiovascular sequelae in the offspring including hypertension and altered vascular function.

Do the body mass index and the diagnosis of gestational diabetes mellitus influence the level of physical activity during pregnancy and postpartum?

Obesity and lack of physical exercise are associated with the increase of diabetes mellitus in women of reproductive age and during the gestational period. The objective of the present study was to evaluate physical activity levels during the pregnancy and postpartum periods and the influence of body mass index (BMI) in women with gestational diabetes mellitus (GDM) or low risk pregnancy. The Pregnancy Physical Activity Questionnaire (PPAQ), translated and validated for Portuguese, was used for the evaluation of physical activity (PA) level. The sample was stratified according to preconception BMI and the presence or absence of diagnosis of GDM, resulting in four groups with 66 participants each: low risk pregnancy (LRP) with normal weight (BMI ≥ 18.5 and ≤ 24 kg/m2), LRP and overweight/obese (BMI ≥ 25 kg/m2), GDM with normal weight and GDM with overweight/obese. The level of PA of each participant was measured as Metabolic Equivalent of Task (MET) during the preconceptional period (T0), in the third trimester of gestation (T1), and three months after delivery (T2). The comparison of the MET values showed that the values found in the evaluation three months after delivery (T2) were higher than 1.00 (1.10 MET for the LRP-normal weight, 1.06 MET for LRP-overweight/obese, 1.02 MET for the GDM- normal weight, 1.07 MET for the GDM-overweight/obese). On the pre-gestational (T0) and third trimester (T1) analyzes, the values were less than 1.00 MET. The analysis between groups in relation to BMI and diagnosis of GDM showed no difference.

Benefits of Physical Activity during Pregnancy and Postpartum: An Umbrella Review

PURPOSE

This study aimed to summarize the evidence from the 2018 Physical Activity Guidelines Advisory Committee Scientific Report, including new evidence from an updated search of the effects of physical activity on maternal health during pregnancy and postpartum.

METHODS

An initial search was undertaken to identify systematic reviews and meta-analyses published between 2006 and 2016. An updated search then identified additional systematic reviews and meta-analyses published between January 2017 and February 2018. The searches were conducted in PubMed®, CINAHL, and Cochrane Library and supplemented through hand searches of reference lists of included articles and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

RESULTS

The original and updated searches yielded a total of 76 systematic reviews and meta-analyses. Strong evidence demonstrated that moderate-intensity physical activity reduced the risk of excessive gestational weight gain, gestational diabetes, and symptoms of postpartum depression. Limited evidence suggested an inverse relationship between physical activity and risk of preeclampsia, gestational hypertension, and antenatal anxiety and depressive symptomology. Insufficient evidence was available to determine the effect of physical activity on postpartum weight loss, postpartum anxiety, and affect during both pregnancy and postpartum. For all health outcomes, there was insufficient evidence to determine whether the relationships varied by age, race/ethnicity, socioeconomic status, or prepregnancy weight status.

CONCLUSIONS

The gestational period is an opportunity to promote positive health behaviors that can have both short- and long-term benefits for the mother. Given the low prevalence of physical activity in young women in general, and the high prevalence of obesity and cardiometabolic diseases among the U.S. population, the public health importance of increasing physical activity in women of childbearing age before, during, and after pregnancy is substantial.

Metformin for prevention of hypertensive disorders of pregnancy in women with gestational diabetes or obesity: systematic review and meta-analysis of randomized trials

OBJECTIVE

Metformin has been reported to reduce the risk of pre-eclampsia. It is also known to influence soluble fms-like tyrosine kinase-1 level, which correlates significantly with the gestational age at onset and severity of pre-eclampsia. The main aim of this systematic review and meta-analysis of randomized trials was to determine whether metformin use is associated with the incidence of hypertensive disorders of pregnancy (HDP).

METHODS

MEDLINE (1947 to September 2017), Scopus (1970 to September 2017) and the Cochrane Library (inception to September 2017) were searched for relevant citations in the English language. Only randomized controlled trials on metformin use, reporting the incidence of pre-eclampsia or pregnancy-induced hypertension, were included. Studies on populations with a high probability of metformin use prior to randomization (those with type II diabetes or polycystic ovary syndrome) were excluded. Random-effects models with the Mantel-Haenszel method were used for subgroup analyses. Bayesian random-effects meta-regression was used to summarize the evidence.

RESULTS

In total, 3337 citations matched the search criteria. After evaluating 2536 abstracts and performing full-text review of 52 studies, 15 were included in the review. In women with gestational diabetes, metformin use was associated with a reduced risk of pregnancy-induced hypertension when compared with insulin (relative risk (RR), 0.56; 95% CI, 0.37-0.85; I²  = 0%; 1260 women) and a non-significantly reduced risk of pre-eclampsia (RR, 0.83; 95% CI, 0.60-1.14; I²  = 0%; 1724 women). In obese women, when compared with placebo, metformin use was associated with a non-significant reduction in risk of pre-eclampsia (RR, 0.74; 95% CI, 0.09-6.28; I²  = 86%; 840 women). In women with gestational diabetes, metformin use was also associated with a non-significant reduction in risk of any HDP (RR, 0.71; 95% CI, 0.41-1.25; I²  = 0%; 556 women) when compared with glyburide. When studies were combined using Bayesian random-effects meta-regression, with treatment type as a covariate, the posterior probabilities of metformin having a beneficial effect on the prevention of pre-eclampsia, pregnancy-induced hypertension and any HDP were 92.7%, 92.8% and 99.2%, respectively, when compared with any other treatment or placebo.

CONCLUSIONS

There is a high probability that metformin use is associated with reduced HDP incidence when compared with other treatments or placebo. The small number of studies included in the analysis, the low quality of evidence and the clinical heterogeneity preclude generalization of these results to broader populations. Given the clinical importance of this topic and the magnitude of effect observed in this meta-analysis, further prospective trials are urgently needed. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Diet and Lifestyle Before and During Pregnancy - Practical Recommendations of the Germany-wide Healthy Start - Young Family Network

Diet and exercise before and during pregnancy affect the course of the pregnancy, the child's development and the short- and long-term health of mother and child. The Healthy Start - Young Family Network has updated the recommendations on nutrition in pregnancy that first appeared in 2012 and supplemented them with recommendations on a preconception lifestyle. The recommendations address body weight before conception, weight gain in pregnancy, energy and nutritional requirements and diet (including a vegetarian/vegan diet), the supplements folic acid/folate, iodine, iron and docosahexaenoic acid (DHA), protection against food-borne illnesses, physical activity before and during pregnancy, alcohol, smoking, caffeinated drinks, oral and dental hygiene and the use of medicinal products. Preparation for breast-feeding is recommended already during pregnancy. Vaccination recommendations for women planning a pregnancy are also included. These practical recommendations of the Germany-wide Healthy Start - Young Family Network are intended to assist all professional groups that counsel women and couples wishing to have children and during pregnancy with uniform, scientifically-based and practical information.

The effect of exercise during pregnancy on gestational diabetes mellitus in normal-weight women: a systematic review and meta-analysis

Background

Gestational diabetes mellitus (GDM) is one of the most common complications during pregnancy, and it has both short- and long-term adverse effects on the health of mothers and fetuses. To investigate the effect of exercise during pregnancy on the occurrence of GDM among normal-weight pregnant women.

Methods

We searched for studies published between January 1994 and June 2017 that appeared in the Web of Science, Scopus, ClinicalTrials.gov or Cochrane library databases. Randomized controlled trials that investigated the preventive effect of exercise on GDM in normal-weight women were included. Interventions including any confounding factors (e.g., dietary) were excluded. We extracted maternal characteristics, the diagnostic criteria of GDM, and basic information for intervention and obstetric outcomes. The primary outcome was the occurrence of GDM, and the secondary outcomes included gestational weight gain, gestational age at birth, birth weight, and the odds of cesarean section. A meta-analysis was conducted based on calculations of pooled estimates using the random-effects model.

Results

Eight studies were included in this systematic review and meta-analysis. Exercise during pregnancy was shown to decrease the occurrence of GDM [RR = 0.58, 95% CI (0.37, 0.90), P = 0.01 and RR = 0.60, 95% CI (0.36, 0.98), P = 0.04 based on different diagnosis criteria, respectively] in normal-weight women. Regarding secondary outcomes, exercise during pregnancy can decrease gestational weight gain [MD = − 1.61, 95% CI (− 1.99, − 1.22), P<0.01], and  had no significant effects on gestational age at birth [MD = − 0.55, 95% CI (− 1.57, 0.47), P = 0.29], birth weight [MD = − 18.70, 95% CI (− 52.49, 15.08), P = 0.28], and the odds of caesarean section [RR = 0.88, 95% CI (0.72, 1.08), P = 0.21], respectively.

Conclusions

Exercise during pregnancy can ostensibly decrease the occurrence of GDM without reducing gestational age at delivery and increasing the odds of cesarean section in normal-weight women.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-2068-7) contains supplementary material, which is available to authorized users.

Prenatal exercise for the prevention of gestational diabetes mellitus and hypertensive disorders of pregnancy: a systematic review and meta-analysis

Objective

Gestational diabetes mellitus (GDM), gestational hypertension (GH) and pre-eclampsia (PE) are associated with short and long-term health issues for mother and child; prevention of these complications is critically important. This study aimed to perform a systematic review and meta-analysis of the relationships between prenatal exercise and GDM, GH and PE.

Design

Systematic review with random effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were included (except case studies) if published in English, Spanish or French, and contained information on the Population (pregnant women without contraindication to exercise), Intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone [“exercise-only”] or in combination with other intervention components [e.g., dietary; “exercise + co-intervention”]), Comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and Outcomes (GDM, GH, PE).

Results

A total of 106 studies (n=273 182) were included. ‘Moderate’ to ‘high’-quality evidence from randomised controlled trials revealed that exercise-only interventions, but not exercise+cointerventions, reduced odds of GDM (n=6934; OR 0.62, 95% CI 0.52 to 0.75), GH (n=5316; OR 0.61, 95% CI 0.43 to 0.85) and PE (n=3322; OR 0.59, 95% CI 0.37 to 0.9) compared with no exercise. To achieve at least a 25% reduction in the odds of developing GDM, PE and GH, pregnant women need to accumulate at least 600 MET-min/week of moderate-intensity exercise (eg, 140 min of brisk walking, water aerobics, stationary cycling or resistance training).

Summary/conclusions

In conclusion, exercise-only interventions were effective at lowering the odds of developing GDM, GH and PE.

Validation of the Fitbit Zip and Fitbit Flex with pregnant women in free-living conditions

Physical activity (PA) is a part of a healthy pregnancy. To date, no consumer-based activity monitors have been validated with this population. The aim of this study was to validate the Fitbit Zip and Fitbit Flex monitors in free-living conditions with pregnant women using the ActiGraph GT3X as the ?gold standard?. We compared the accuracy of the Fitbit Zip and Fitbit Flex devices in measuring steps, sedentary time and time spent in different activity intensities. Sixteen women in their third trimester of pregnancy wore the ActiGraph GT3X (hip) plus one Fibit Zip (hip) and one Fitbit Flex (wrist) during seven consecutive days. The validity of Fitbit Zip and Fitbit Flex is good, depending on measured parameters. Fitbit Zip is accurate to measure steps whereas Fitbit Flex is precise for MVPA. When choosing between Fitbit Zip and Fitbit Flex monitors, pregnant women should take into account their preferred PA and the parameters they want to measure..

Diet and exercise for preeclampsia prevention in overweight and obese pregnant women: systematic review and meta-analysis

Objective: To investigate the effect of diet and/or exercise in overweight or obese pregnant women on the risk of preeclampsia (PE). Methods: We performed a systematic review and meta-analysis of randomized controlled trials examining the effect of diet and/or exercise interventions in overweight and obese pregnant women on the risk of PE and hypertensive disorders. We completed a literature search through PubMed, Embase, Cinahl, Web of science, Cochrane CENTRAL Library from their earliest entries to November 2017 and from references of other systematic reviews. No language restrictions were applied. Relative risks (RR) with random effect were calculated with their 95% confidence intervals (CI). Results: There were 23 eligible trials (7236 participants), including 11 (5023 participants) investigating the effect of diet and three (387 participants) investigating the effect of exercise on risk of PE, 14 (4345 participants) investigating the effect of diet, five (884 participants) investigating the effect of exercise and one (304 participants) investigating the effect of diet and exercise on risk of hypertensive disorders. Most studies were considered to be at low risk of bias for random sequence allocation and incomplete outcome data but at high risk of bias for blinding of participant and personnel. The heterogeneity of the studies on PE was low (I² = 0-11%), but the heterogeneity of the studies on hypertensive disorders was variable (I² = 0-53%). In women randomized to diet and/or exercise, compared to expectant management, there was no significant difference in the risk of PE (RR 1.01, 95% CI 0.80-1.27; p = .96) or hypertensive disorders of pregnancy (RR 0.87, 95% CI 0.70-1.06; p = .17). In the intervention group, compared to expectant management, gestational weight gain was significantly lower (-1.47 kg, 95% CI -1.97 to -0.97; p < .00001). Metaregression weighted by the size of the studies showed no significant association between gestational weight gain and the risk of PE or hypertensive disorders (p = .314 and p = .124, respectively). Conclusions: Diet and exercise in overweight or obese pregnant women are beneficial in reducing gestational weight gain. However, these interventions do not reduce the risk of PE or hypertensive disorders of pregnancy.

Effects of exercise during pregnancy in women with short cervix: Secondary analysis from the Italian Pessary Trial in singletons

OBJECTIVE

To evaluate effects of exercise during pregnancy in asymptomatic singleton pregnancies without prior spontaneous preterm birth (SPTB) but with short transvaginal ultrasound cervical length (TVU CL).

STUDY DESIGN

This is a secondary analysis of the Italian Pessary Trial for the Italian Preterm Birth Prevention (IPP) Working Group. In the original prospective randomized controlled trial asymptomatic singleton pregnancies without prior SPTB but with TVU CL ≤ 25 mm at 18 0/6-23 6/7 weeks were randomized into 1:1 ratio to either cervical pessary or no pessary. During their follow-up visits, women were asked about their activity. For the purpose of this secondary analysis, women were classified in the following groups, using the information obtained in the follow-up visit one month after randomization: 1) Exercise group, defined as women performing exercise ≥2 days a week for ≥20 min each day. 2) No exercise group, defined as women performing exercise <2 days a week for ≥20 min each day. The primary outcome of this secondary analysis was PTB < 37 weeks.

RESULTS

300 women were included in this analysis. 99 (33.0%) were included in the exercise group. 201 (67.0%) were included in the no exercise group. Of the 201 women in the no exercise group, 90 (44.8%) affirmed that they had reduced their activity after the diagnosis of short cervix despite the research staff recommendations, while the other 111 (55.2%) women performed a sedentary life style even before the diagnosis of short cervix. PTB < 37 weeks occurred in 22 women (22.2%) in the exercise group, and 66 women (32.8%) in the no exercise group (aOR 0.65, 95% CI 0.33-1.03).

CONCLUSION

In asymptomatic singleton pregnancies with short cervix, performing exercise ≥2 days a week for ≥20 min each day does not increase the risk of PTB but is indeed associated with a non-significant reduction in PTB < 37 weeks by 32%.

Resistant Hypertension in Pregnancy: How to Manage?

PURPOSE OF REVIEW

The concept of resistant hypertension may be changed during pregnancy by the physiological hemodynamic changes and the particularities of therapy choices in this period. This review discusses the management of pregnant patients with preexisting resistant hypertension and also of those who develop severe hypertension in gestation and puerperium.

RECENT FINDINGS

The main cause of severe hypertension in pregnancy is preeclampsia, and differential diagnosis must be done with secondary or primary hypertension. Women with preexisting resistant hypertension may need pharmacological therapy adjustment. Several drugs can be used to treat severe hypertension, with exception of angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists. The most used drugs are methyldopa, beta-blockers, and calcium channel antagonists. There is a general agreement that severe hypertension must be treated, but there are still debates over the goals of the treatment. Delivery is indicated in viable pregnancies in which blood pressure control is not achieved with three drugs in full doses. Resistant hypertension may arise in postpartum. The management of resistant hypertension in pregnancy must regard the possible etiology, the fetal well-being, and the mother's risk. Good care is mandatory to reduce maternal mortality risk.

[Preeclampsia: A challenge also for cardiologists]

Due to its short-term consequences on perinatal outcome, preeclampsia has been long regarded as an obstetrical disease, strictly confined to a management by OB/GYNs. It has been now widely accepted that preeclampsia is most a systemic inflammatory and systemic vascular disease during pregnancy and then a lifelong risk factor for subsequent cardiovascular event in women's life. The aim of this review is to propose an overview in the current state-of-art in definition, early identification and management of preeclampsia. We will also discuss the growing evidence that support that cardiologists must be fully involved in screening and prevention of preeclampsia during pregnancy and beyond in the subsequent medical follow-up of women who have experienced a preeclampsia.

Hypertension in pregnancy: Taking cues from pathophysiology for clinical practice

Pregnancy-related hypertension (PHTN) syndromes are a frequent and potentially deadly complication of pregnancy, while also negatively impacting the lifelong health of the mother and child. PHTN appears in women likely to develop hypertension later in life, with the stress of pregnancy unmasking a subclinical hypertensive phenotype. However, distinguishing between PHTN and chronic hypertension is essential for optimal management. Preeclampsia (PE) is linked to potentially severe outcomes and lacks effective treatments due to poorly understood mechanisms. Inadequate remodeling of spiral uterine arteries (SUAs), the cornerstone of PE pathophysiology, leads to hypoperfusion of the developing placenta. In normal pregnancies, extravillous trophoblast (EVT) cells assume an invasive phenotype and invade SUAs, transforming them into large conduits. Decidual natural killer cells play an essential role, mediating materno-fetal immune tolerance, inducing early SUA remodeling and regulating EVT invasiveness. Notch signaling is important in EVT phenotypic switch and is dysregulated in PE. The hypoxic placenta releases antiangiogenic and proinflammatory factors that converge upon maternal endothelium, inducing endothelial dysfunction, hypertension, and organ damage. Hypoxia-inducible factor 1-α is upstream of such molecules, whereas endothelin-1 is a major effector. We also describe important genetic links and evidence of incomplete materno-fetal immune tolerance, with PE patients presenting with autoantibodies, lower Treg , and higher Th 17 cells. Thus, PE manifestations arise as a consequence of mal-placentation or/and because of a predisposition of the maternal vascular bed to excessively react to pathogenic molecules. From this pathophysiological basis, we provide current and propose future therapeutic directions for PE.

Mechanisms and Clinical Significance of Endothelial Dysfunction in High-Risk Pregnancies

The maternal cardiovascular system undergoes critical anatomic and functional adaptations to achieve a successful pregnancy outcome which, if disrupted, can result in complications that significantly affect maternal and fetal health. Complications that involve the maternal cardiovascular system are among the most common disorders of pregnancy, including gestational hypertension, preeclampsia, gestational diabetes, and impaired fetal growth. As a central feature, maternal endothelial dysfunction is hypothesized to play a predominant role in mediating the pathogenesis of these high-risk pregnancies, and as such, might proceed and precipitate the clinical presentation of these pregnancy disorders. Improving or normalizing maternal endothelial function in high-risk pregnancies might be an effective therapeutic strategy to ameliorate maternal and fetal clinical outcomes.

Decrease in the incidence of threatened preterm labor after implementation of transvaginal ultrasound cervical length universal screening

BACKGROUND

It is unknown if universal second-trimester transvaginal ultrasound (TVU) cervical length (CL) screening in asymptomatic women with singleton gestations and no prior spontaneous preterm birth (SPTB) affects the incidence of symptoms of preterm labor (PTL) later in pregnancy.

OBJECTIVE

To evaluate the incidence of threatened PTL before and after the implementation of universal second trimester TVU CL screening.

STUDY DESIGN

This was a retrospective cohort study of all consecutive singleton gestations without prior SPTB presenting to obstetric triage for threatened PTL between 23 0/7 and 33 6/7 week in 2011 (1 January-31 December), and in 2014 (1 January-31 December) at Thomas Jefferson University Hospital (TJU) (Philadelphia, PA). These 2 years were chosen as a new protocol for universal TVU CL screening was started on 1 January 2012. This protocol involved one measurement of TVU CL in all singleton gestations without a prior SPTB at 18 0/7 - 23 6/7 week, the time of the "anatomy" scan. Women with prior SPTB were excluded from this study. The primary outcome included the incidence of threatened PTL, defined as the number of women with singleton gestations without prior SPTB who presented with threatened PTL to our labor and delivery (L&D) triage unit annually, divided by the total number of annual deliveries of women with singleton gestation without prior SPTB. Secondary outcomes were the incidence of PTL, defined as the number of women with singleton gestations without prior SPTB admitted for PTL annually divided by the total number of annual deliveries of women with singleton gestation and without prior SPTB; and length of stay in the hospital. We aimed to compare primary and secondary outcome in the "2011" versus the "2014" group.

RESULTS

In 2011, there were a total of 1745 deliveries at TJU, of which 1550 (88.8%) were singletons without prior SPTB. In 2014, there were a total of 1924 deliveries at TJU, 1751 (91.0%) were singletons without prior SPTB who were offered universal TVU CL screening. One hundred and seventy-two women with singletons without prior SPTB presented in L&D triage unit in 2011; and 118 women with singletons without prior SPTB presented in L&D triage unit in 2014. There were significant decreases in the incidence of threatened PTL from 11.1% (172/1550) in 2011 to 6.7% (118/1751) in 2014 (p < .001), as well as in the rate of admission for PTL from 2.3% (35/1550) to 1.4% (24/1751), respectively (p = .04). Length of stay was not significantly different between the two groups.

CONCLUSION

The introduction of a universal TVU CL screening program in women with singleton gestations without a history of SPTB is associated with a reduction in the frequency of threatened PTL and admission for PTL. Key Message The introduction of a second trimester universal transvaginal ultrasound (TVU) cervical length (CL) screening program in women without a history of spontaneous preterm birth (SPTB) is associated with a reduction in the incidence of threatened preterm labor (PTL) and admission for PTL.

Obesity and Weight Gain in Pregnancy and Postpartum: an Evidence Review of Lifestyle Interventions to Inform Maternal and Child Health Policies

Background: Maternal obesity, excessive gestational weight gain (GWG) and post-partum weight retention (PPWR) constitute new public health challenges, due to the association with negative short- and long-term maternal and neonatal outcomes. The aim of this evidence review was to identify effective lifestyle interventions to manage weight and improve maternal and infant outcomes during pregnancy and postpartum. Methods: A review of systematic reviews and meta-analyses investigating the effects of lifestyle interventions on GWG or PPWR was conducted (Jan 2009-2018) via electronic searches in the databases Medline, Pubmed, Web of Science and Cochrane Library using all keywords related to obesity/weight gain/loss, pregnancy or postpartum and lifestyle interventions;15 relevant reviews were selected. Results: In healthy women from all BMI classes, diet and physical activity interventions can decrease: GWG (mean difference -1.8 to -0.7 kg, high to moderate-quality evidence); the risks of GWG above the IOM guidelines (risk ratio [RR] 0.72 to 0.80, high to low-quality evidence); pregnancy-induced hypertension (RR 0.30 to 0.66, low to very low-quality evidence); cesarean section (RR 0.91 to 0.95; high to moderate-quality evidence) and neonatal respiratory distress syndrome (RR 0.56, high-quality evidence); without any maternal/fetal/neonatal adverse effects. In women with overweight/obesity, multi-component interventions can decrease: GWG (-0.91 to -0.63 kg, moderate to very low-quality evidence); pregnancy-induced hypertension (RR 0.30 to 0.66, low-quality evidence); macrosomia (RR 0.85, 0.73 to 1.0, moderate-quality evidence) and neonatal respiratory distress syndrome (RR 0.47, 0.26 to 0.85, moderate-quality evidence). Diet is associated with greater reduction of the risks of GDM, pregnancy-induced hypertension and preterm birth, compared with any other intervention. After delivery, combined diet and physical activity interventions reduce PPWR in women of any BMI (-2.57 to -2.3 kg, very low quality evidence) or with overweight/obesity (-3.6 to -1.22, moderate to very low-quality-evidence), but no other effects were reported. Conclusions: Multi-component approaches including a balanced diet with low glycaemic load and light to moderate intensity physical activity, 30-60 min per day 3-5 days per week, should be recommended from the first trimester of pregnancy and maintained during the postpartum period. This evidence review should help inform recommendations for health care professionals and women of child-bearing age.

Spousal influence on physical activity in physically inactive pregnant women: A cross-sectional study

Regular physical activity (PA) is recommended during pregnancy, but the prevalence of pregnant women who met the recommended level for PA is very low. In this descriptive study, we examined the association between spousal characteristics (belief, knowledge, social support, and PA level) and pregnant women's PA level in 18 couples living in the San Francisco Bay Area. Among other spousal characteristics, only spousal PA level was a significant predictor of pregnant women's PA level regardless of whether it was unadjusted or adjusted by spouses' age and body index mass (p = .01). Our finding shows a need to develop strategies to incorporate spousal support for PA.

Discontinuing Oxytocin Infusion in the Active Phase of Labor: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the benefits and harms of discontinuation of oxytocin after the active phase of labor is reached.

DATA SOURCES

Electronic databases (ie, MEDLINE, Scopus, ClinicalTrials.gov, EMBASE, ScienceDirect, the Cochrane Library at the CENTRAL Register of Controlled Trials, Scielo) were searched from their inception until April 2017.

METHODS OF STUDY SELECTION

We included all randomized controlled trials comparing discontinuation (ie, intervention group) and continuation (ie, control group) of oxytocin infusion after the active phase of labor is reached, either after induction or augmentation of labor. Discontinuation of oxytocin infusion was defined as discontinuing oxytocin infusion when the active phase of labor was achieved. Continuation of oxytocin infusion was defined as continuing oxytocin infusion until delivery. Only trials in singleton gestations with vertex presentation at term were included. The primary outcome was the incidence of cesarean delivery.

TABULATION, INTEGRATION, AND RESULTS

Nine randomized controlled trials, including 1,538 singleton gestations, were identified as relevant and included in the meta-analysis. All nine trials included only women undergoing induction of labor. In the discontinuation group, if arrest of labor occurred, usually defined as no cervical dilation in 2 hours or inadequate uterine contractions for 2 hours or more, oxytocin infusion was restarted. Women in the control group had oxytocin continued until delivery usually at the same dose used at the time the active phase was reached. Women who were randomized to have discontinuation of oxytocin infusion after the active phase of labor was reached had a significantly lower risk of cesarean delivery (9.3% compared with 14.7%; relative risk 0.64, 95% CI 0.48-0.87) and of uterine tachysystole (6.2% compared with 13.1%; relative risk 0.53, 95% CI 0.33-0.84) compared with those who were randomized to have continuation of oxytocin infusion until delivery. Discontinuation of oxytocin infusion was associated with an increase in the duration of the active phase of labor (mean difference 27.65 minutes, 95% CI 3.94-51.36).

CONCLUSION

In singleton gestations with cephalic presentation at term undergoing induction, discontinuation of oxytocin infusion after the active phase of labor at approximately 5 cm is reached reduces the risk of cesarean delivery and of uterine tachysystole compared with continuous oxytocin infusion. Given this evidence, discontinuation of oxytocin infusion once the active stage of labor is established in women being induced should be considered as an alternative management plan.

Maternal exercise during pregnancy reduces the risk of preterm birth through the mediating role of placenta

OBJECTIVE

The extent of research on maternal exercise during pregnancy and the risk of preterm birth (PTB) have grown substantially, but conclusions still remained controversial. Thus, this study aims to examine the relationship of maternal exercise during pregnancy and PTB and explore whether placenta mediates their relationship.

STUDY DESIGN

We investigated 849 pregnant women delivering PTB newborns (cases) and 1306 delivering full-term appropriate for gestational age newborns (controls) in this case-control study. Information concerning maternal exercise during pregnancy, sociodemographics and obstetric characteristics were collected at Women and Children's Hospitals of Shenzhen and Foshan in Guangdong, China. A series of logistic and linear regressions were used to examine the relationships of maternal exercise during pregnancy, placenta, and PTB.

RESULTS

After adjusting for the potential confounders, maternal exercise frequency and duration during pregnancy were negatively associated with PTB. Moreover, compared with mother taking no exercise during pregnancy, those taking exercise lowered the risk of PTB except those taking low/medium frequency and short duration exercise, and their adjusted ORs ranged from 0.43 to 0.65. Furthermore, mediation analysis illustrated that placental weight partially mediated 65.20% of the effects of maternal exercise frequency on PTB, as well as 41.98% of the association between maternal exercise duration and PTB.

CONCLUSIONS

Maternal exercise during pregnancy is beneficial for lowering the risk of PTB, especially when taking appropriate and enough exercise. Placenta weight may partially mediate the association between maternal exercise during pregnancy and PTB.

The influence of prenatal exercise and pre-eclampsia on maternal vascular function

During healthy pregnancy, the cardiovascular system undergoes diverse adaptations to support adequate transfer of oxygen and nutrients from mother to fetus. In order to accommodate the large expansion of blood volume and associated cardiac output, the structure, mechanics, and function of the arteries are altered. Specifically, in healthy pregnancy there is a remodeling of arteries (increased angiogenesis and vasodilation), a generalized reduction in arterial stiffness (increased compliance), and an enhanced endothelial function. The development of pregnancy complications, specifically pre-eclampsia, is associated with poor placentation (decreased angiogenesis), increased arterial stiffness, and vascular dysfunction (reduced endothelial function). Many of the positive adaptations that occur in healthy pregnancy are enhanced in response to chronic exercise. Specifically, placental angiogenesis and endothelial function have been shown to improve to a greater extent in women who are active during their pregnancy compared with those who are not. Prenatal exercise may be important in helping to reduce the risk of vascular dysfunction in pregnancy. However, our knowledge of the vascular adaptations resulting from maternal exercise is limited. This review highlights maternal vascular adaptations occurring during healthy pregnancy, and contrasts the vascular maladaptation associated with pre-eclampsia. Finally, we discuss the role of prenatal exercise on vascular function in the potential prevention of vascular complications associated with pre-eclampsia.

Interventions for treating hyperemesis gravidarum: a Cochrane systematic review and meta-analysis

INTRODUCTION

While nausea and vomiting in early pregnancy are very common, affecting approximately 80% of the pregnancies, hyperemesis gravidarum is a severe form affecting 0.3-1.0% of the pregnancies. Although hyperemesis gravidarum is rarely a source of mortality, it is a significant source of morbidity. It is one of the most common indications for hospitalization in pregnancy. Beyond the maternal and fetal consequences of malnutrition, the severity of hyperemesis symptoms causes a major psychosocial burden leading to depression, anxiety, and even pregnancy termination. The aim of this meta-analysis was to examine all randomized controlled trials of interventions specifically for hyperemesis gravidarum and evaluate them based on both subjective and objective measures of efficacy, maternal and fetal/neonatal safety, and economic costs.

MATERIAL AND METHODS

Randomized controlled trials were identified by searching electronic databases. We included all randomized controlled trials for the treatment of hyperemesis gravidarum. The primary outcome was intervention efficacy as defined by severity, reduction, or cessation in nausea/vomiting; number of episodes of emesis; and days of hospital admission. Secondary outcomes included other measures of intervention efficacy, adverse maternal/fetal/neonatal outcomes, quality of life measures, and economic costs.

RESULTS

Twenty-five trials (2052 women) met the inclusion criteria but the majority of 18 different comparisons described in the review include data from single studies with small numbers of participants. Selected comparisons reported below: No primary outcome data were available when acupuncture was compared with placebo. There was insufficient evidence to identify clear differences between acupuncture and metoclopramide in a study with 81 participants regarding reduction/cessation in nausea or vomiting (risk ratio (RR) 1.40, 95% CI 0.79-2.49 and RR 1.51, 95% CI 0.92-2.48, respectively). Midwife-led outpatient care was associated with fewer hours of hospital admission than routine inpatient admission (mean difference (MD) - 33.20, 95% CI -46.91 to -19.49) with no difference in pregnancy-unique quantification of emesis and nausea (PUQE) score, decision to terminate the pregnancy, miscarriage, small-for-gestational age infants, or time off work when compared with routine care. Women taking vitamin B6 had a slightly longer hospital stay compared with placebo (MD 0.80 days, 95% CI 0.08-1.52). There was insufficient evidence to demonstrate a difference in other outcomes including mean number of episodes of emesis (MD 0.50, 95% CI -0.40-1.40) or side effects. A comparison between metoclopramide and ondansetron identified no clear difference in the severity of nausea or vomiting (MD 1.70, 95% CI -0.15-3.55, and MD -0.10, 95% CI -1.63-1.43; one study, 83 women, respectively). However, more women taking metoclopramide complained of drowsiness and dry mouth (RR 2.40, 95% CI 1.23-4.69, and RR 2.38, 95% CI 1.10-5.11, respectively). There were no clear differences between groups for other side effects. In a single study with 146 participants comparing metoclopramide with promethazine, more women taking promethazine reported drowsiness, dizziness, and dystonia (risk ratio (RR) 0.70, 95% CI 0.56-0.87, RR 0.48, 95% CI 0.34-0.69, and RR 0.31, 95% CI 0.11-0.90, respectively). There were no clear differences between groups for other important outcomes including quality of life and other side effects. In a single trial with 30 women, those receiving ondansetron had no difference in duration of hospital admission compared to those receiving promethazine (mean difference (MD) 0.00, 95% CI -1.39-1.39), although there was increased sedation with promethazine (RR 0.06, 95% CI 0.00-0.94). Regarding corticosteroids, in a study with 110 participants there was no difference in days of hospital admission compared to placebo (MD -0.30, 95% CI -0.70-0.10), but there was a decreased readmission rate (RR 0.69, 95% CI 0.50-0.94; 4 studies, 269 women). For hydrocortisone compared with metoclopramide, no data were available for primary outcomes and there was no difference in the readmission rate (RR 0.08, 95% CI 0.00-1.28; one study, 40 women). In a study with 80 women, compared to promethazine, those receiving prednisolone had increased nausea at 48 h (RR 2.00, 95% CI 1.08-3.72), but not at 17 days (RR 0.81, 95% CI 0.58-1.15). There was no clear difference in the number of episodes of emesis or subjective improvement in nausea/vomiting.

CONCLUSIONS

While there were a wide range of interventions studied, both pharmaceutical and otherwise, there were a limited number of placebo controlled trials. In comparing the efficacy of the commonly used antiemetics, metoclopramide, ondansetron, and promethazine, the results of this review do not support the clear superiority of one over the other in symptomatic relief. Other factors such as side effect profile medication safety and healthcare costs should also be considered when selecting an intervention.