Exercise as it relates to Disease/Decreasing the risk of perinatal depression through a physical exercise program during pregnancy

This Wikibook is a critique of the journal article "Physical exercise programme during pregnancy decreases perinatal depression risk" by Vargas-Terrones et al. (2018). This was written as an assessment item for the Health, Disease and Exercise unit at the University of Canberra, 2021.

What is the background to this research?
Perinatal depression consists of minor and major depressive episodes occurring either during pregnancy or within the first 12 months following birth. The prevalence of prenatal depression ranges from 5%-21%, and depression remains high after birth. Furthermore, approximately 10%-19% of women are affected by postnatal depression. Pharmacological treatment is typically the main option after diagnosis. However, there is often reluctance for breastfeeding mothers to take antidepressants due to the concern of potentially harming their baby. Various interventions have explored the prevention of perinatal depression and alternatives to pharmacological treatment; yet there is little evidence regarding the effect of exercise during pregnancy on postnatal depression. Research indicates an association between physical activity and a decreased risk of depressive symptoms , and exercise has been proposed as a non-pharmacological intervention to alleviate postnatal depression. Very few clinical trials have been conducted to determine the impact of exercise on postnatal depression. The aim of this study was to evaluate how participating in a structured exercise program (EP) during early pregnancy effected mood status in later pregnancy and postnatally.

Where is the research from?
Vargas-Terrones and Santacruz have a firm reputation in this study field, having completed 9 and 17 studies respectively. Barakat, Fernandez-Buhigas and Mottola have all been involved in at least 5 studies.

The analysts are from the following institutions:


 * Department of Social Sciences of Physical Activity, Sports and Leisure, INEF, Technical University of Madrid (UPM), Madrid, Spain
 * Department of Obstetrics and Gynecology, University Hospital of Torrejon, Madrid, Spain
 * R Samuel McLaughlin Foundation - Exercise and Pregnancy Laboratory, School of Kinesiology, The University of Western Ontario, London, Ontario, Canada

The authors of this article did not declare a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors. This suggests that there should be no conflicts of interest or bias in the findings.

What kind of research was this?
This study was a randomised controlled trial (RCT) conducted across 2 years. Participants were randomly allocated into either an intervention (IG) or control group (CG).

What did the research involve?
Depression levels were assessed using the Center for Epidemiological Studies-Depression (CES-D) Scale at the beginning of the study (gestational weeks 12–16), at the end of pregnancy (gestational week 38–39) and at 6 weeks postnatally. A score of >16 indicated depression. After birth, women in the CG had 6 follow-up visits, and the IG had 50.

Body Mass Index (BMI) and maternal gestational weight gain (GWG) were used to conduct an analysis. The women were categorised using pregnancy BMI as either excessive or adequate. Excessive GWG is defined for each classification of BMI according to the Institute of Medicine recommendations in the table below.

Exercise Intervention
The EP was conducted in a hospital fitness room. Women participated in three sessions per week from gestation weeks 12-16 to gestation weeks 38-40. Levels of exhaustion were measured using the The Borg Rate of Perceived Exertion (RPE) scale. Each session had 10-12 participants and lasted 60 minutes consisting of warm up, aerobic, muscle strengthening, balance and pelvic floor exercises and stretching.

Limitations:

 * Depressive symptomatology may have been prevented due to socialisation being promoted through groups.
 * The variation in the size of the groups, maybe due to the simple randomised method (n=70 vs n=54)
 * The lack of follow-up sessions in the CG compared to the IG.
 * Only measuring postnatal depression 6 weeks post-delivery thus lacking information for the following 11 months.

What were the basic results?
The drop out rates between the CG and IG were significant, with a rate of 13% and 1.4% respectively. The results from this intervention are based off different analysis methods - a protocol analysis, intention-to-treat (simple imputation -SI) and intention-to-treat (multiple imputation - MI). The results indicated that, the groups had no significant differences in percentage of women with depression according to the CES-D at baseline. In the protocol analysis, the percentage of depressed women was significantly lower in the IG than the CG at week 38 and 6 weeks postnatally (p=0.046). Results from the intention-to-treat analysis differ. There were no significant differences in the SI analysis at week 38 (p=0.060) and 6 weeks postnatally (p=0.063). Contrastingly, the MI analysis found significant results at week 38 (p=0.049), yet no differences at 6 weeks postnatally (p=0.079). A significant treatment effect was found in the per-protocol (p=0.024) and the SI (p=0.037) analyses (see figure 1.0).

Among women who gained excessive GW, the CG had a significantly higher percentage of women with depression at week 38 (p=0.002) and at 6 weeks postnatal (p=0.023). No differences were found among women with an adequate GWG (p>0.05). The IG had a significantly lower percentage of depressed women than the CG at week 38 (p=0.030) for the pre-pregnancy normal-weight BMI.

What conclusions can we take from this research?
It can be concluded that participating in an EP has a positive impact on lowering perinatal depression. I think this study is a solid foundation for this topic, and provides positive results, however conducting a similar investigation with a larger population would provide beneficial.These findings correlate with other RCTs stating that postnatal exercise may prevent postnatal depression and may be a feasible treatment for women with postnatal depression.

Practical advice
It is recommended that pregnant women don't exceed 200 minutes of moderate-intensity aerobic activity each week. The following exercises are encouraged for pregnant women:

It is important that a training plan is developed by a qualified professional and that pregnant women are not pushed beyond their limits hindering the health of themselves or their baby.
 * Walking
 * Swimming and water workouts
 * Riding a stationary bike
 * Yoga/Pilates
 * Low-impact aerobic classes
 * Strength training

Further information/resources
For support during pregnancy and after birth contact the following organisations:

Perinatal Wellbeing Centre

PANDA - Perinatal Anxiety and Depression Australia:

COPE - Centre of Perinatal Excellence:

Gidget Foundation Australia:

Exercise in pregnancy:

Raising Children Network: https://raisingchildren.net.au/pregnancy/health-wellbeing/healthy-lifestyle/exercise-in-pregnancy-for-women#:~:text=It's%20safe%20for%20you%20to,day%2C%205%20days%20a%20week.