Clinical and PICO Question
A 30-year-old female G1P1001 with no PMH presents to the office with a PHQ-9 score of 8. She reports she has been feeling depressed with little interest in doing things she used to enjoy and difficulty sleeping since the birth of her daughter 6 weeks ago. She plans on having another child but does not want to feel the same way she feels now.

In women seeking to reduce depressive symptoms and prevent postpartum depression, are exercise-based interventions more effective than non-intervention or standard care [antidepressants or cognitive behavioral therapy]? 

PICO Search Elements   

P	I	C	O
Postpartum depression	Exercise	Standard care	Prevention
Postnatal depression	Physical activity	Non-intervention	Reduction
Postpartum depressive symptoms	Exercise-based interventions		Reduced depressive symptoms
Postpartum period

Search Strategy

PubMed 

• Search terms: postpartum depression, exercise, standard care, prevention 

• • MEDLINE indexed and published within the past 5 years: 807 results 

• Search terms: postpartum depression, exercise-based interventions, reduced depressive symptoms 

• • MEDLINE indexed and published within the past 5 years: 31 results 

• Search terms: postpartum depressive symptoms, physical activity, non-intervention, reduction 

• • MEDLINE indexed and published within the past 5 years: 28 results 

Google Scholar 

• Search terms: postpartum depression, exercise, standard care, reduced depressive symptoms 

• • Published within the past 5 years: 17,200 results 

• Search terms: postpartum depressive symptoms, exercise-based intervention, prevention 

• • Published within the past 5 years: 455 results 

• Search terms: postpartum depression, physical activity, non-intervention, prevention 

• • Published within the past 5 years: 312 results 

 Science Direct 

• Search terms: postpartum depression, physical activity, non-intervention, reduction 

• • Published within the past 5 years: 972 results 

• Search terms: postpartum depression, exercise, non-intervention, prevention 

• • Published within the past 5 years: 536 results 

• Search terms: postpartum depression, exercise, standard care, reduced depressive symptoms 

• • Published within the past 5 years: 352 results 

I narrowed down the choices for my selected articles by evaluating which articles specifically studied the effect of physical activity on postpartum depression, as it is a non-pharmacologic intervention that can provide both physical and mental benefits for women with depressive symptoms. While research is limited, I concluded that the articles selected are of the highest quality available, including systematic reviews and meta-analyses. All of the articles are also MEDLINE indexed and recently published within the past five years.  

Articles Chosen  

1. Physical Activity and the Occurrence of Postnatal Depression—A Systematic Review 

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6780177/

Background and Objectives: During pregnancy and the postnatal period many changes occur in a woman’s body, both in mental and physical spheres. The birth of a child and a new role—of a mother—can sometimes be associated with numerous negative emotions, uncertainty, fear, anxiety, disgust, depression, or sadness. In the puerperium period, the development of baby blues or postpartum depression may occur. Postpartum depression develops within one month of childbirth and may last up to one year. Depressive disorders that may develop in a young mother affect both her and the newborn’s health. That is why it is so important to try to search for factors that could significantly reduce the likelihood of developing depression in this period. The study aims at assessing the relationship between physical activity during pregnancy and puerperium or in the postpartum and the development of postnatal depression. 

Materials and Methods: A review of the literature was carried out in the Medline-PubMed database. The search terms were “pregnancy” AND “physical activity AND postpartum depression”. The study included only English-language publications published in the period 2000–2018. 

Results: A total of 216 references were found. After establishing the inclusion and exclusion criteria based on the analysis of titles and abstracts, 173 articles were excluded from the review. A total of 43 publications were read in full. Finally, 16 articles were included in the review. It was shown that regular physical activity during pregnancy, pregnancy, and puerperium, or in the postnatal period itself as compared to inactivity, reduces the risk of developing depression in pregnant women and after the birth of a child. 

Conclusions: Physical activity can be an essential factor in the prevention of depressive disorders of women in the postnatal period. 

2. Physical activity during pregnancy and postpartum depression: Systematic review and meta-analysis

Link: https://www-sciencedirect-com.york.ezproxy.cuny.edu/science/article/pii/S0165032718318779 

Background: It is still largely unknown whether physical activity (PA) during pregnancy may be useful to avert subsequent postpartum depression (PPD). We conducted a systematic review and meta-analysis to determine the preventive effects of PA during pregnancy on PPD. 

Methods: A systematic review of English and non-English articles was conducted using CINAHL, Cochrane Controlled Trials Register, PsycINFO, MEDLINE, SportDiscuss and Web of Science databases. Studies which tested the effect of any type of PA measured during pregnancy on depression or depressive symptoms in the first year postpartum were included. Relevant articles were extracted independently by 2 authors using predefined data fields, including study quality indicators. The protocol was registered on PROSPERO (CRD42018087086). 

Results: Twenty one studies, fit our selection criteria. Among them, seventeen studies were included in the meta-analysis, representing 93 676 women. Robust Variance Estimation random-effects meta-analysis indicated a significant reduction in postpartum depression scores (Overall SMD = -0.22 [95% CI −0.42 to −0.01], p = 0.04; I2 = 86.4%) for women physically active during pregnancy relative to those who were not active. This association was reinforced in intervention studies (SMD = −0.58 [9% CI −1.09 to −0.08]). 

Limitations: Overall meta-analysis showed important heterogeneity in PA assessment, suggesting the existence of potential moderators such as intensity, frequency, trimester of pregnancy or type of physical activity practiced. 

Conclusions: PA during pregnancy appears to reduce the risk of PPD symptoms. High quality studies addressing the role of PA in the perinatal period and its impact on new mother’s mental health remain necessary. 

3. The effectiveness of exercise-based interventions for preventing or treating postpartum depression: a systematic review and meta-analysis

Link: https://link-springer-com.york.ezproxy.cuny.edu/article/10.1007/s00737-018-0869-3 

Postpartum depression can have detrimental effects on both a mother’s physical and mental health and on her child’s growth and emotional development. The aim of this study is to assess the effectiveness of exercise/physical activity-based interventions in preventing and treating postpartum depressive symptoms in primiparous and multiparous women to the end of the postnatal period at 52 weeks postpartum. Electronic databases were searched for published and unpublished randomised controlled trials of exercise/physical activity-based interventions in preventing and treating depressive symptoms and increasing health-related quality of life in women from 4 to 52 weeks postpartum. The results of the studies were meta-analysed and effect sizes with confidence intervals were calculated. The Grading of Recommendations Assessment and Development and Evaluation (GRADE) system was used to determine the confidence in the effect estimates. Eighteen trials conducted across a range of countries met the inclusion criteria. Most of the exercise interventions were aerobic and coaching compared to usual care, non-intervention and active controls. Small effect sizes of exercise-based interventions in reducing depressive symptoms were observed collectively and the quality of evidence was low across the individual studies. Although exercise-based interventions could create an alternative therapeutic approach for preventing major depression in postpartum women who experience subthreshold elevated depressive symptoms, the clinical effectiveness and the cost-effectiveness of exercise-based and physical activity interventions need to be better established. There is a need for further more rigorous testing of such interventions in high-quality randomised controlled trials against active control conditions before large-scale roll-out of these interventions in clinical practice is proposed. 

4. Does aerobic exercise reduce postpartum depressive symptoms? a systematic review and meta-analysis

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5604832/ 

Background: There is currently no specific guidance on the role of exercise in managing postpartum depression in the UK and US, and international guidance is inconsistent.

Aim: To assess the effectiveness of aerobic exercise on postpartum depressive symptoms.

Design and setting: Systematic review and meta-analysis. There was no restriction to study site or setting.

Method: The databases MEDLINE, EMBASE, Cochrane Library, PsycINFO, SportDiscus, Clinical Trials.gov, and the World Health Organization International Clinical Trials Registry Platform were searched. Titles and abstracts, then full-text articles, were screened against inclusion criteria: RCTs measuring depressive symptoms in mothers ≤1 year postpartum; and interventions designed to increase aerobic exercise compared with usual care or other comparators. Included studies were assessed using the Cochrane Collaboration’s risk of bias tool. Meta-analysis was conducted. Pre-planned subgroup analyses explored heterogeneity.

Results: Thirteen RCTs were included, with 1734 eligible participants. Exercise significantly reduced depressive symptoms when all trials were combined (standardised mean difference –0.44; 95% confidence interval = –0.75 to –0.12). Exploration of heterogeneity did not find significant differences in effect size between women with possible depression and in general postpartum populations; exercise only and exercise with co-interventions; and group exercise and exercise counselling.

Conclusion: This systematic review provides support for the effectiveness of exercise in reducing postpartum depressive symptoms. Group exercise, participant-chosen exercise, and exercise with co-interventions all may be effective interventions. These results should be interpreted with caution because of substantial heterogeneity and risk of bias.

5. Effects of exercise-based interventions on postpartum depression: A meta-analysis of randomized controlled trials 

Link: https://onlinelibrary-wiley-com.york.ezproxy.cuny.edu/doi/10.1111/birt.12294

Background: There is inconsistent evidence about the effect of physical activity on the prevention and treatment of depression during the postnatal period. The aim of this meta-analysis was to determine the effect of physical activity interventions during pregnancy and the postpartum period for controlling postpartum depressive symptoms. 

Methods: We systematically searched Cochrane Library Plus, Science Direct, EMBASE, CINAHL, PubMed, Web of Science, and Scopus, from January 1990 to May 2016, for randomized or nonrandomized controlled trials addressing the effect of physical activity on postpartum depression. The inverse variance-weighted method was used to compute pooled estimates of effect size and respective 95% confidence intervals (95% CI) for physical activity intervention on postpartum depression. Subgroup analyses were performed comparing women with and without postpartum depressive symptoms according to specific scales measuring this construct. Meta-regression and sensitivity analysis were computed to evaluate heterogeneity. 

Results: Twelve studies were included in the meta-analysis. Effect size for the relationship between physical activity interventions during pregnancy and the postpartum period on postpartum depressive symptoms was 0.41 (95% CI 0.28-0.54). Heterogeneity was I2 = 33.1% (P = .117). When subgroup analyses were done, pooled effect sizes were 0.67 (95% CI 0.44-0.90) for mothers who met postpartum depressive symptoms criteria at baseline based on specific scales, and 0.29 (95% CI 0.14-0.45) for mothers who did not meet those depressive symptoms criteria at baseline. 

Conclusion: Physical exercise during pregnancy and the postpartum period is a safe strategy to achieve better psychological well-being and to reduce postpartum depressive symptoms.

6. Effects of Exercise on Mild-to-Moderate Depressive Symptoms in the Postpartum Period: A Meta-analysis 

Link: https://pubmed.ncbi.nlm.nih.gov/28486363/ 

Objective: To examine the influence of exercise on depressive symptoms and the prevalence of depression in the postpartum period. 

Data sources: A structured search of MEDLINE, EMBASE, CINAHL, Sport Discus, Ovid’s All EBM Reviews, and ClinicalTrials.gov databases was performed with dates from the beginning of the databases until June 16, 2016. The search combined keywords and MeSH-like terms including, but not limited to, “exercise,” “postpartum,” “depression,” and “randomized controlled trial.” 

Methods of study selection: Randomized controlled trials comparing postpartum exercise (structured, planned, repetitive physical activity) with the standard care for which outcomes assessing depressive symptoms or depressive episodes (as defined by trial authors) were assessed. Trials were identified as prevention trials (women from the general postpartum population) or treatment trials (women were classified as having depression by the trial authors). Effect sizes with 95% confidence intervals (CIs) were calculated using Hedges’ g method and standardized mean differences in postintervention depression outcomes were pooled using a random-effects model. 

Tabulation, integration, and results: Across all 16 trials (1,327 women), the pooled standardized mean difference was -0.34 (95% CI -0.50 to -0.19, I=37%), suggesting a small effect of exercise among all postpartum women on depressive symptoms. Among the 10 treatment trials, a moderate effect size of exercise on depressive symptoms was found (standardized mean difference-0.48, 95% CI -0.73 to -0.22, I=42%). In six prevention trials, a small effect (standardized mean difference-0.22, 95% CI -0.36 to -0.08, I=2%) was found. In women with depression preintervention, exercise increased the odds of resolving depression postintervention by 54% (odds ratio 0.46, Mantel-Haenszel method, 95% CI 0.25-0.84, I=0%). The trials included in this meta-analysis were small and some had methodologic limitations. 

Conclusion: Light-to-moderate intensity aerobic exercise improves mild-to-moderate depressive symptoms and increases the likelihood that mild-to-moderate depression will resolve. 

Summary of the Evidence 

Author (Date)	Level of Evidence	Sample/Setting  (# of subjects/ studies, cohort definition etc.)		Outcome(s) studied	Key Findings	Limitations and Biases
Kolomanska-Bogucka, D. et al. (2019)	Systematic Review	16 RCTs including 3,083 participants, published in the English language  between 2008-2018  Inclusion criteria: RCTs with examinations completed on pregnant and puerperal women or only during the postpartum assessing the relationship between physical activity and postpartum depression  Exclusion criteria: studies published in a language other than English, studies not related to women in the postpartum period, studies that did not examine the impact of exercise on the development of postnatal depression, research other than RCTs, studies that lacked clearly described results, studies that lacked standardized scales to assess postnatal depression		Relationship between physical activity during pregnancy and puerperium or in the postpartum and the development of postnatal depression  Type, intensity, and duration of exercise to prevent or minimize the risk of developing depressive disorders in the postpartum period	Physical activity during pregnancy or puerperium may minimize the risk of development as well as symptoms of postnatal depression  Regular physical activity in the second and third trimester of pregnancy significantly reduces the risk of developing depression both in pregnancy and in the postpartum  Light or moderate physical activity, including walking training and resistance training, effectively reduces the level and symptoms of postpartum depression  Physical activity not only minimizes the risk of developing postnatal depression but also significantly improves the quality of life of women in childbirth  Regular physical activity eliminates the risk of developing depression during pregnancy and is a safe form of preventative treatment  Women who were physically active before or during pregnancy had a lower risk of developing depressive disorders compared to women who were physically inactive	Studies in other languages outside of English were excluded and may have provided further support for or against the study’s findings
Nakamura, A. et al. (2019)	Systematic review and meta-analysis	21 studies [6 interventional and 15 observational] including 100,494 women who were on average between the ages pf 25 and 32 years old, published between 1993-2018  Inclusion criteria: RCTs, retrospective and prospective cohorts, case-control and cross-sectional studies, studies that tested the effect of any type of physical activity measured at least once during pregnancy on depression or depressive symptoms in the first year after childbirth, subjects diagnosed using a structured clinical interview, screened for probable depression using a validated, such as the Edinburgh Postnatal Depression Scale, or diagnosed according to a health professional’s judgment  Exclusion criteria: qualitative studies, comments, editorials and studies on animals, studies that did not measure physical activity during pregnancy, studies that combined physical activity with other interventions or treatment [i.e. diet, behavioral therapy, or antidepressant medication], studies in which depression was measured exclusively before/during pregnancy or more than one year after delivery		Whether physical activity performed during pregnancy reduces the risk of depression in the postpartum period	Pregnant women who were physically active for five or more days per week had fewer postpartum depressive symptoms compared to those who were active for one or less than one day per week  No optimal duration, intensity, or timing was defined due to the diversity of exercise-based interventions that would have otherwise allowed for meaningful comparisons. Though, it should be noted that group exercise may offer the added effect of social support for some women.  Physical activity during pregnancy could prevent the occurrence of postpartum depressive symptoms  Physical activity of moderate intensity for at least 30 minutes one to four times per week may contribute to reducing postpartum depression risk, with both aerobic and strength-based physical activity found to be equally effective	Information regarding duration, intensity, and timing was lacking or too diverse to make meaningful comparisons
Carter, T. et al. (2019)	Systematic review and meta-analysis	17 studies [3 from Australia, 3 from the UK, 6 from the U.S., 1 from Canada, 1 from Japan, 1 from Iran, 1 from Taiwan, and 1 from India], including 1,428 participants, published between 1974-2017  Inclusion criteria: published or unpublished individual RCTs or cluster RCTs that enrolled primiparous or multiparous postnatal women, exercise-based intervention (supervised, unsupervised, coaching-based, motivational, behavioral-oriented, universal, targeted or treatment based, in a community or clinical context) compared to any type of control condition (flexibility/stretching or social support sessions, usual care, non-intervention, active control, or waitlist control) with outcomes of depression symptoms using a validated assessment tool, such as Edinburgh Postnatal Depression Scale or a  Patient Health Questionnaire  Exclusion criteria: non-RCTs, pregnant women, women with psychiatric diagnoses other than depression, studies with no details of the exercise component, intervention delivered before 4 weeks or after 52 weeks, studies with no depression symptom measure, and outcomes before 4 weeks postpartum		Primary outcome: depression symptoms in postpartum women at post-intervention  Secondary outcomes: symptoms of anxiety and health-related quality of life	There is a statistically significant moderate treatment effect of exercise over control conditions for depression symptoms in postpartum women up to 52 weeks after childbirth, with likely additional physical benefits in managing weight and physical activity and improving confidence, body image, and mood  Exercise-based interventions targeting at-risk women with a history of depression or elevated depression symptoms postpartum were found to have increased treatment effects than universal preventive interventions  Interventions with active exercise-oriented components were found to have greater effects than those with coaching or motivational components  Interventions with shorter duration were also found to have a larger effect size than those of longer duration	Small number of studies limiting the strength of the conclusions made  Limited findings regarding the effects of exercise on health-related quality of life as only 2 studies were included in the meta-analysis
Pritchett, R.V. et al (2017)	Systematic review and meta-analysis	13 RCTs [4 conducted in the U.S., 3 in England, UK, 2 in Australia, 1 in Canada, 1 in India, 1 in Japan, and 1 in Taiwan], including 1,734 participants, published between 2003-2015  Inclusion criteria: RCTs, mothers <1 year postpartum, interventions designed to increase aerobic exercise, including those with co-interventions, such as social support or nutrition elements, comparator groups receiving no care or any form of usual care, depressive symptoms measured by questionnaire or diagnostic interview  Exclusion criteria: trials comparing two types of exercise		Investigate the effect of aerobic exercise interventions compared with usual care on depressive symptoms in women up to one year postpartum	Exercise interventions significantly reduced depressive symptoms in depressed postpartum populations  Group exercise interventions and exercise with co-interventions had a significant effect in reducing depressive symptoms as did participant choice interventions, such as exercise counselling with personal choice of exercise [often exercise alone]  Overall, exercise has a positive effect in reducing postpartum depressive symptoms with various interventions that have been found to be effective	Only included studies with intervention designed to increase aerobic exercise rather than different forms of exercise  7 trials were considered at high risk of bias with 6 trials at unclear risk   Substantial amount of heterogeneity between populations and in the design of trials and interventions
Poyatos-Leon, R. et al. (2017)	Meta-analysis	12 studies with a total sample of 932 women [471 in the intervention group versus 461 in the control group] across Canada, Iran, China, the U.S., UK, Taiwan, and Australia, published between 2003-2015  Women who met the depressive symptoms criteria as well as women who did not meet the criteria at baseline were included  Inclusion criteria:  RCTs or non-RCTs that included healthy pregnant women without contraindications for doing exercise, with a single fetus and an uncomplicated pregnancy, or women who had a child aged between 6 weeks and 18 months, maternal well-being assessed on a depression scale [i.e. Edinburgh Postnatal Depression Score or the Beck Depression Inventory], and physical activity programs that started during pregnancy and extended to the puerperium period or were only developed during the puerperium period  Studies were excluded if there was insufficient data to calculate effect size, physical activity interventions were implemented only during pregnancy, or not in English or Spanish	Effect of physical activity interventions during pregnancy and the postpartum period for controlling postpartum depressive symptoms		Control group was given usual prenatal care while the intervention group was involved in physical activity programs conducted during the postpartum period or during pregnancy  Physical activity programs included stretching and breathing exercises, a walking program, cardiovascular exercises, mixed cardiovascular and strength exercises, pilates and yoga exercises, and home-based programs  Frequency of the physical activity interventions varied from one to five days per week with intensity being low, moderate, or moderate to high  Overall, physical activity programs during pregnancy and the postpartum period were found to be effective in controlling and reducing depressive symptoms regardless of frequency or intensity  Notably, individualized interventions tailored to the mother’s previous fitness level of moderate or moderate to high intensity were reported to have higher levels of adherence	Studies had variable dropout rates between 10% and 30% due to patients not having enough time, a new pregnancy, moving to another state, or mother or baby health problems
McCurdy, A. P. et al. (2017)	Meta-analysis	16 RCTs, including 1,327 postpartum participants, where 10 trials examined the effect of exercise on treatment and 6 trials evaluated the prevention of postpartum depression and depressive symptoms, published between 2003-2015  Inclusion criteria: RCTs in postpartum women with and without depression comparing exercise, supervised or unsupervised, plus standard care (antidepressants and psychotherapy) versus standard care alone on any measure used to assess depressive symptoms in postpartum women  Exclusion criteria: observational studies, wrong population, animal studies, irrelevant intervention, studies with no outcome measure provided, studies with interventions not defined or meeting the definition of exercise, non-RCTs	Primary outcomes: depressive symptoms assessed using questionnaires and diagnosis of depression based on cut-off scores [such as greater than 12 on the Edinburgh Depression Scale] or standardized interviews		All of the participants were between 4 and 12 months postpartum when they began the exercise interventions, which included either aerobic exercise, combined aerobic and resistance training, flow yoga, and a whole-body gentle stretching program  Post-intervention depressive symptoms were lower in the exercise groups, both supervised and unsupervised, compared with the control group  Lower Edinburgh Postnatal Depression Scale scores were also reported after the exercise interventions  Exercise in postpartum women was found to have a small to moderate effect in treating depressive symptoms compared with standard care  Light to moderate aerobic exercise was ultimately found to be effective in reducing mild to moderate depressive symptoms in postpartum women	Trials were small with some having methodological limitations

Conclusion(s)
Article 1: Compared to inactivity, physical activity during pregnancy, puerperium, or in the postnatal period reduces the risk of developing depression in pregnant women and in women following childbirth. Additionally, it reduces the symptoms of postpartum depression, including fatigue, and improves quality of life. 
Article 2: Physical activity during pregnancy could prevent the occurrence of postpartum depressive symptoms and in turn lead to long-term benefits for mother’s overall health and well-being.
Article 3: Physical activity can effectively reduce depression symptoms in postpartum women and may provide the most benefit for women with elevated symptoms of depression and if delivered as supervised exercise sessions where active engagement is the focus.
Article 4: Physical activity is an effective treatment for reduction of postpartum depressive symptoms regardless of whether women meet significant criteria for postpartum depression or not.
Article 5: Physical activity during pregnancy and the postpartum period is safe and effective in mitigating and reducing postpartum depressive symptoms and helps to improve psychological well-being.
Article 6: Light to moderate aerobic exercise effectively reduces mild to moderate depressive symptoms in postpartum women and may lead to the resolution of mild to moderate depression.

Overall conclusion: Physical activity during pregnancy and in the postpartum period is a safe, non-pharmacologic intervention that can not only reduce postpartum depressive symptoms, but also effectively prevent the occurrence of postpartum depression and improve overall well-being and quality of life in mothers. 

Weight of the Evidence  
Article 1: This systematic review published in 2019 provides the most updated analysis of reference works up to 2018 whereas previous systematic reviews were based on publications up to and including 2016 or 2017. It also includes a large sample population and only analyzes findings from RCTs from which a more comprehensive analysis of different types of physical activity were studied regarding the development of postpartum depression.
Article 2: This systematic review and meta-analysis published in 2019 provides high quality evidence that was not restricted by date or language. It is the first that investigates the effectiveness of physical activity during pregnancy to prevent postpartum depression. Its large sample size includes 100,494 women between 25 and 32 years old on average, which is within the range of the patient in my case description. Of the 21 studies included, 6 were conducted in the U.S., 11 in Europe (Denmark, France, Norway, Poland, Spain, Sweden, and the UK) and 4 others in Australia, Canada, Iran and South Korea, providing more generalizable results. 
Article 3: This systematic review and meta-analysis published in 2019 only includes RCTs, offers the best quality evidence available, and is the first to include 4 RCTs of exercise for postpartum women that had not been previously included in qualitative and/or quantitative research. It includes studies that were conducted across eight different countries, making findings generalizable. It also includes studies that compared exercise against non-intervention or standard care, which aligns with my clinical question. However, the study’s conclusions are limited by the small number of and quality of the included studies.
Article 4: This systematic review and meta-analysis published in 2017 was restricted to RCTs to reduce the potential for confounding and allowed for the exploration of the effectiveness of exercise in different populations, intervention types, and exercise contexts. It was also not limited by language of publication. The methodological quality of several of the trials was low, however, with an increased risk of bias due to exclusion of non-adherent participants and unclear blinding of outcome assessors.
Article 5: This systematic review and meta-analysis published in 2017 provides high quality evidence and was conducted across seven different countries. It evaluates the effect of intervention with physical activity compared to standard care in women with postpartum depression. In addition, it considers the mental and emotional benefits exercise may provide women in addition to reducing postpartum depressive symptoms. However, studies were limited to including those written in English and Spanish only. Several studies also had considerable dropout rates between 10% and 30%.
Article 6: This meta-analysis published in 2017 includes RCTs only, providing high quality evidence. It also includes trials completed in North America, Europe, Asia, and the Middle East, making findings diverse and generalizable. It specifically evaluates the treatment and reduction of mild to moderate depressive symptoms in postpartum women. Though, only 9 trials provided evidence of allocation concealment, indicating a medium to high risk of bias. Additionally, 5 trials reported that a considerable number of women in both exercise and control groups were taking antidepressants or receiving psychological interventions pre-intervention, affecting the accuracy of the results. 

Magnitude of Effect
Article 1: The percentage of women with depression at 38 weeks in pregnancy was significantly lower among physically active pregnant women compared to inactive women (respectively, 18.6% and 35.6%; p = 0.041). A similar result was obtained in the 6th week of postnatal period (14.5% experimental group (Exp. gr.), 29.8% control group (Con. gr.); p = 0.046. For women who performed resistance training, a significant decrease in the level of depression was recorded by comparing the initial analysis (9.5 ± 6.3) measurement made at four months showed (6.4 ± 4.1). After three months of training at home with DVD instruction, the average level of depression in the experimental group decreased from 16.5 ± 2.6 to 10.2 ± 3.6, and in the control group from 16.3 ± 3.2 to 12.7 ± 3.9. Women from the intervention group with an initial level of depression EPDS > 13 points achieved a significantly lower final result compared to the control group (average difference 4.06, p < 0.001). There was a statistically significant reduction in the level of depressive symptoms in physically active women (6 weeks: 10.2 points in the EPDS; and 12 weeks: 6.3 points). 
Article 2: The Robust Variance Estimation random-effects meta-analysis indicated a significant reduction in postpartum depression scores (Overall SMD = -0.22 [95% CI −0.42 to −0.01], p = 0.04; I2 = 86.4%) for women physically active during pregnancy relative to those who were not active. Intervention studies showed a significant inverse association between physical activity during pregnancy and postpartum depression (SMD = −0.58 [95% CI −1.09 to −0.08], p = 0.02, I2 = 90.7%), indicating that being physically active during pregnancy might prevent PPD. Observational studies also showed an inverse, but not significant, association between physical activity during pregnancy and postpartum depression (SDM = −0.07 [95% CI − 0.20 to 0.06], p = 0.24, I2 = 74.4%). The overall effect of physical activity on postpartum depression symptoms was even stronger (SMD = −0.70 [95%CI −1.19 to-0.22], p = 0.005) for studies with moderate to high intensity.
Article 3: A moderate, significant, SMD, favoring the intervention condition, was found for depressive symptoms (SMD = − 0.64, 95% CI = [− 0.96, − 0.33], p < 0.001. A non-significant SMD, favoring the intervention condition, was found for secondary outcomes: physical function (SMD = − 0.04, 95% CI = [− 0.33, 0.26], p = 0.81; and a non-significant SMD, favoring the control condition, was found for mental function (SMD = 0.27, 95% CI = [− 0.03, 0.56], p = 0.07). Targeted prevention or treatment interventions yielded a greater effect size compared to universal prevention interventions (SMD = − 0.75, 95% CI = [− 1.22, − 0.28], p = 0.002 for the targeted interventions and SMD = − 0.52, 95% CI = [− 0.99, − 0.05], p = 0.03 for universal prevention interventions). Interventions with active exercise-oriented components yielded larger effects than those with coaching/motivational components (SMD = − 1.19, 95% CI = [− 1.84, − 0.53], p = 0.0004 for active exercise interventions and SMD = − 0.21, 95% CI = [− 0.37, − 0.05], p = 0.009 for coaching/ motivational interventions. Interventions with shorter duration (SMD = − 1.72, 95% CI = [− 3.05, − 0.39], p = 0.01) yielded a larger effect sizes than those of longer duration (SMD = − 0.52, 95% CI = [− 0.84, − 0.19], p = 0.002). 
Article 4: Exercise interventions significantly reduced depressive symptoms (SMD –0.44, 95% CI = –0.75 to –0.12, n = 1307, I² 85%,13 trials). The WMD was –1.54 EPDS units, 95% CI = –2.97 to –0.12, n = 652, I² 87%. Exercise interventions had a significant effect in reducing  depressive symptoms in ‘depressed’ postpartum populations  (SMD –0.32, 95% CI = –0.63 to  –0.00), I² 55%) and in general postpartum populations (-0.57, 95% CI = –1.12 to –0.02, I²   92%). Exercise-only interventions had a non-significant effect in reducing depressive symptoms  (SMD –0.56, 95% CI = –1.13 to 0.01, I² 89%). Exercise with co-interventions had a significant effect on reducing depressive symptoms (–0.35, 95% CI = –0.66 to –0.04, I² 72%). Group exercise interventions had a significant effect in reducing depressive symptoms (SMD difference –1.10, 95% CI = –1.99 to –0.21, I² 93%). Participant choice interventions such as exercise counseling with personal choice of exercise (often exercise alone) had a significant effect in reducing depressive symptoms (–0.20, 95% CI = –0.33 to –0.06, I² 0%).
Article 5: For physical activity interventions during pregnancy and the postpartum period versus the control group, there was a decrease in postpartum depressive symptom scores, measured by EPDS or BDI, in favor of the physical activity group (effect size: 0.41; 95% CI 0.28- 0.54). 
Article 6: Post-intervention depressive symptoms were lower in the exercise compared with the control group (n = 1,327; standardized mean difference 20.34, 95% CI 20.50 to 0.19, I² = 37%; small effect size). Analysis including only the 14 trials that used Edinburgh Postnatal Depression Scale as an outcome measure demonstrated lower Edinburgh Postnatal Depression Scale scores after exercise (weighted mean difference 21.92, 95% CI 22.91 to 20.92, I² = 55%). Post-intervention depressive symptoms were lower in both the supervised exercise (standardized mean difference 20.46, 95% CI 20.74 to 20.18, I² = 55%; moderate effect size) and unsupervised exercise groups compared with controls (standardized mean difference 20.25, 95% CI 20.39 to 20.11, I² = 0%; small effect size). Across 10 trials of women identified by trial authors to have depression in the postpartum period, exercise had a moderate effect in treating depressive symptoms (standardized mean difference 20.48, 95% CI 20.73 to 20.22, I² = 42%; moderate effect size). Three trials of women with depression pre-intervention (n = 173) also reported on the prevalence of depression after the intervention. These trials demonstrated resolution of depression was improved by 54% after the exercise intervention (OR 0.46, 95% CI 0.25 –0.84, I² = 0%).  

Clinical Significance
Article 1: Pregnant women and young mothers should be informed about the positive benefits of physical activity as their well-being significantly impacts their children’s development.
Article 2: Due to findings that indicate physical activity can reduce the risk of antenatal depression, which is predictive of postnatal depression, it is important to promote physical activity during the prenatal period. Engaging in at least 30 minutes of moderate intensity physical activity one to four times per week could contribute to reducing the risk of postpartum depression.
Article 3: Besides reducing symptoms of depression, physical activity may also provide additional physical benefits, such as improved confidence, body image, and mood. It is also an effective alternative for lactating mothers who are unwilling to take antidepressant medications.
Article 4: Physical activity offers additional health benefits of improved physical fitness and weight loss, which are outcomes that are specifically relevant to postpartum women, who tend to experience decreased exercise levels and excess weight. There were no detrimental effects of moderate levels of aerobic exercise reported. Thus, it is a safe, low-cost intervention that should be considered to both manage and prevent depressive symptoms in postpartum women.
Article 5: In addition to reducing depression and anxiety, physical activity during pregnancy and the postpartum period can improve mood, body image, cardiorespiratory fitness, weight control, and physical performance. Such improvement can lead to positive effects on feelings of self-confidence and self-worth.
Article 6: Exercise is an accessible and cost-efficient treatment option for postpartum women seeking to reduce depressive symptoms. It also reduces chronic disease risk, controls weight, and reduces stress. 

Other Considerations 
Article 1: Before beginning any type of physical activity, pregnant women should consult with their providers regarding the most appropriate recommendation for exercise interventions.
Article 2: This study was not able to determine if physical activity is more effective in preventing postpartum depression during a specific trimester of pregnancy in contrast to Article 1. Evidence was also either lacking or too diverse to report meaningful comparisons on duration, intensity, and timing of physical activity. Further studies should therefore be conducted to distinguish the most optimal frequency and type of interventions including the role of timing of physical activity in pregnancy or postpartum.
Article 3: Exercise-based interventions for postpartum depression symptom reduction is promising. Though, larger, high-quality RCTs comparing exercise interventions against one control, such as non-intervention, are needed to more strongly support current findings on a large scale.
Article 4: This study did not effectively assess exercise duration and intensity. Future studies should include objective measures of exercise to allow for greater accuracy and more meaningful comparisons between intervention types.
Article 5: Interventions customized to the mother’s previous fitness level may lead to the greatest benefit and should be considered. Participants in this study were volunteers. As such, the reported levels of compliance may not be as generalizable or accurate. 
Article 6: This study was unable to identify the optimal intensity or type of exercise for improving depressive symptoms. Though, it is suggested that aerobic exercise, which the majority of trials assessed, is effective in treating postpartum depression. 

Clinical Bottom Line
Postpartum depression is a public health concern that is highly prevalent among women, affecting up to 22% in the first year after delivery. Because the consequences of postpartum depression may negatively affect both the mother, with respect to increased risk of future depressive episodes, and baby, in terms of physical and emotional development, let alone compromised mother-baby relationship, it is important to determine optimal management to prevent such negative consequences. At present, the American Congress of Obstetricians and Gynecologists (ACOG) recommends that pregnant women engage in 150 minutes of moderate intensity aerobic activity per week. Due to the finding that physical activity is beneficial in the treatment of depression in the general population, it is suggested that adherence to ACOG’s recommendation may have an additional protective effect in preventing postpartum depression. 

The available evidence regarding the effect of physical activity on postpartum depression is limited with some low quality RCTs and a small to moderate effect size. However, current findings suggest that exercise, including aerobic exercise, yoga, pilates, walking, resistance training, and strength training, is a safe, low-cost, non-pharmacologic intervention that can lead to the prevention of postpartum depression and reduction of depressive symptoms. More specifically, initiation of regular physical activity in the second and third trimesters has been found to be significantly effective. Unlike treatment with antidepressants or cognitive behavioral therapy, which may not be as accessible to patients of lower socioeconomic status, physical activity comes without stigma or side effects. It is also an effective alternative for lactating mothers who do not wish to take anti-depressant medication due to concerns of transmission through breastmilk. Therefore, I would recommend the initiation of exercise to the patient in my case scenario, encouraging moderate intensity physical activity a few times a week in efforts to prevent postpartum depression. Still, because of its high prevalence, further high-quality studies must be conducted to better elucidate the most appropriate management of postpartum depression with respect to factors, such as optimal intensity, type, and frequency of exercise. Nevertheless, it is important to consider how such factors may be patient dependent, in which case individualized exercise programs may offer maximal benefit.