Effects of Exercise During Pregnancy on Maternal and Child Health: a Randomized Clinical Trial (PAMELA)

The Pamela Study is a clinical trial carried out during pregnancy to assess the potential effects of physical activity during pregnancy among previously inactive women. The trial is nested into a birth cohort of more than 4000 dyads (mother-child) and took place in Pelotas, Brazil.

Study Overview

• Status: Completed
• Conditions: Prematurity; Gestational Hypertension; Maternal Post-partum Depression; Maternal Post-partum Weight Retention; Child's Development
• Intervention / Treatment: Behavioral: Physical Exercise / Physical Activity

Detailed Description

Introduction World Health Organization estimates that nearly 10% of births are preterm worldwide. In the city of Pelotas, based on previous population studies, the preterm birth rate is increasing (6.3% to 14.7% from 1982 to 2004). Preterm birth (PB) is a major public health issue as it is associated to most cases of neonatal deaths and its consequences are linked to later health outcomes.

One of the strongest predictors of PB is gestational hypertension (or eclampsia). PB risk and gestational hypertension may be altered by maternal behavior, such as leisure-time physical activity (LTPA), and overall maternal health influences the likelihood of both outcomes occurring. Biological plausibility lies on the fact that hypertension conditions are potentially influenced by LTPA directly or indirectly (as in the relation between excessive gestational weight gain and physical activity). Also, there is evidence that mental health plays a role in the determination of PB and, although biased by cross-sectional nature of studies, literature shows that physical activity may influence positively psychological aspects during pregnancy.

In Brazil less than 20% of pregnant women are physically active during leisure. Physical activity during pregnancy is associated to several characteristics resulting in improved health profiles that could potentially decrease hypertension occurrence and consequently preterm birth rates. However, few clinical trials have been carried out to study such relationship in representative population samples and many of the available evidence are based solely on observational studies.

Although early studies on the effects of leisure-time physical activity during pregnancy were concerned about potential harmful effects to the health of the mother and the fetus, these have not been proven over time. Currently, there is growing evidence supporting the safe promotion of physical activity during pregnancy targeting benefits to maternal and child health. However, most of the scientific evidence derives from observational studies. There is an urgent need for results from well-designed experimental studies that enable a better understanding of the impact of exercise during pregnancy on various health outcomes maternal and child.

Methodology The intervention will start after the 12th and before the 20th week of gestation and will last until the end of pregnancy or when women feel uncomfortable with the exercise routine. The intervention will consist of three weekly exercise sessions. Each session will last around 60 minutes and will include aerobic exercises (treadmill or stationary cycling) and strength training (with focus on major muscle groups and pregnancy-specific exercises to help alleviate low back pain and work abdominal and pelvic floor muscles to prevent urinary incontinence). Workouts will be guided and supervised by physical education professionals previously trained. The intensity of the exercises will be set according to woman's fitness level and will be altered according to the progress of pregnancy based on the perceived effort. All exercise sessions will take place at the School of Physical Education from the Federal University of Pelotas.

• Study Type: Interventional
• Enrollment (Actual): 639
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • Rio Grande Do Sul
    • Pelotas, Rio Grande Do Sul, Brazil, 96055-630
      • Physical Education School

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Pregnant women who are at least in their 20th week of gestation, living in the city of Pelotas (Brazil), whose deliveries are due to 2015 and belonging to the 2015 Birth Cohort.

Exclusion Criteria:

• Hypertension
• Diabetes
• Preterm birth history
• Miscarriage history
• Heart disease
• In vitro fertilization
• Twin pregnancy
• Persistent bleeding
• Body mass index above 35kg/m2
• Heavy smokers (above 20 cigarettes/day)
• Active women (>150 min/week of physical activity).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Lifestyle intervention; Physical Exercise / Physical Activity. Exercise intervention, three weekly sessions. Each session will last around 60 minutes and will include aerobic exercises (treadmill or stationary cycling) and strength training (with focus on major muscle groups and pregnancy-specific exercises to help alleviate low back pain and work abdominal and pelvic floor muscles to prevent urinary incontinence).	Behavioral: Physical Exercise / Physical Activity; Lifestyle intervention Exercise intervention, three weekly sessions. Each session will last around 60 minutes and will include aerobic exercises (treadmill or stationary cycling) and strength training (with focus on major muscle groups and pregnancy-specific exercises to help alleviate low back pain and work abdominal and pelvic floor muscles to prevent urinary incontinence).
No Intervention: Control Group; A group of eligible women, twice as large as the intervention group, will not receive the exercise intervention but will be followed-up equally to compare outcomes in the future.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prematurity	By the end of the intervention, after birth, the gestational age of each child will be measured to assess the preterm birth rate.	Women will be interviewed at hospital soon after birth (up to 2 days after delivering)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maternal post-partum depression	A follow-up study will be carried out to assess post-partum maternal depression, comparing intervention and control women.	3 months after the end of intervention
Child's development	During the follow-up visits that will take place in the early years of childhood, children from mothers enrolled in the intervention/control groups will be compared with neurodevelopment screening tools.	Children will be followed-up and evaluated by the ages of 3, 12 and 24 months of age

Collaborators and Investigators

• Sponsor: Federal University of Pelotas

Publications and helpful links

General Publications

• Coll CVN, Domingues MR, Stein A, da Silva BGC, Bassani DG, Hartwig FP, da Silva ICM, da Silveira MF, da Silva SG, Bertoldi AD. Efficacy of Regular Exercise During Pregnancy on the Prevention of Postpartum Depression: The PAMELA Randomized Clinical Trial. JAMA Netw Open. 2019 Jan 4;2(1):e186861. doi: 10.1001/jamanetworkopen.2018.6861.
• da Silva SG, Hallal PC, Domingues MR, Bertoldi AD, Silveira MFD, Bassani D, da Silva ICM, da Silva BGC, Coll CVN, Evenson K. A randomized controlled trial of exercise during pregnancy on maternal and neonatal outcomes: results from the PAMELA study. Int J Behav Nutr Phys Act. 2017 Dec 22;14(1):175. doi: 10.1186/s12966-017-0632-6.
• Domingues MR, Bassani DG, da Silva SG, Coll Cde V, da Silva BG, Hallal PC. Physical activity during pregnancy and maternal-child health (PAMELA): study protocol for a randomized controlled trial. Trials. 2015 May 24;16:227. doi: 10.1186/s13063-015-0749-3.

Helpful Links

• Epidemiology Research Center

Study record dates

Study Major Dates

• Study Start: September 1, 2014
• Primary Completion (Actual): June 1, 2016
• Study Completion (Actual): September 1, 2016

Study Registration Dates

• First Submitted: May 22, 2014
• First Submitted That Met QC Criteria: May 27, 2014
• First Posted (Estimate): May 29, 2014

Study Record Updates

• Last Update Posted (Actual): September 29, 2021
• Last Update Submitted That Met QC Criteria: September 27, 2021
• Last Verified: September 1, 2021

More Information

Terms related to this study

• Keywords: hypertension; clinical trials; pregnancy; motor activity; cohort studies
• Additional Relevant MeSH Terms: Mental Disorders; Cardiovascular Diseases; Vascular Diseases; Mood Disorders; Body Weight; Pregnancy Complications; Body Weight Changes; Puerperal Disorders; Depressive Disorder; Weight Gain; Hypertension; Depression, Postpartum; Hypertension, Pregnancy-Induced; Gestational Weight Gain
• Other Study ID Numbers: PAMELA-649.244; Wellcome Trust - 522.064 (Other Grant/Funding Number: Wellcome Trust)