Impact of Exercise Prescription on Obstetric and Neonatal Outcomes

The aim of this study is to assess the impact of structured physical activity with smartwatch remote monitoring on glycemic control, blood pressure control, obstetric complications and neonatal outcomes in women with GDM, chronic hypertension and obesity. A prospective, longitudinal, single-arm intervention study with 310 pregnant women was conducted over a period of 18 months. Participants received individualized exercise prescriptions based on international guidelines, complemented by smartwatch monitoring and regular telephonic feedback. Outcomes were compared between subgroups of women who adhere to the recommended exercise guidelines and those who did not, across three high-risk populations (GDM, chronic hypertension and obesity).

Study Overview

• Status: Completed
• Conditions: Diabetes During Pregnancy; Hypertension ,Pregnancy; Obesity (BMI>30)
• Intervention / Treatment: Behavioral: Physical activity plan; Behavioral: Women who received information but did not engaged in a physical activity routine

Detailed Description

A prospective, longitudinal, single-arm, intervention (prospective cohort) study was conducted in the Obstetric Department of Hospital of Coimbra, Portugal, for a total period of 18 months after a one-year recruitment period between February 2024 and January 2025, with data collection continuing until the final participant had given birth.

Clinical monitoring for high-risk pregnancies takes place solely in a hospital setting. This includes at least monthly visits and standardized trimester ultrasounds, with supplementary scans schedule as needed for fetal development and well-being based on the underlying conditions.

All pregnant patients attending their first obstetric consultation for either Endocrinology/Obstetric (if diagnosis of gestational diabetes or obesity with previous bariatric surgery) or Hypertension/Obstetric (if chronic hypertension) were recruited for the trial.

Study participants were enrolled via screening referrals initiated by both internal or external healthcare providers.

At the first visit, pregnant women were notified of an upcoming telephone contact from the research team. After clinical record verification, a phone interview was conducted to explain the project and collect demographic, anthropometric and obstetric data. After confirming the absence of exercise contraindications, researchers assessed the participants' pre-pregnancy healthy lifestyle habits.

Subsequently, participants received proactive counselling on the exercise modalities most effective for their specific pathologies, including guidance on the intensity, frequency and duration required for optimal health outcomes. This intervention included information on local exercise facilities and access to digital platforms (YouTube Channel - Active Pregnancy) featuring safe, evidence-based activities tailored for pregnancy. Prescriptions were individualized, incorporating patient preferences to determine the most suitable activity types and schedules.

Participants were equipped with a smartwatch to monitor physical activity, specifically tracking heart rate, step count, distance and average speed throughout the pregnancy. They were instructed to activate the device's 'training' mode at the commencement of each exercise session. Subsequently, activity data were synced to a dedicated mobile application for later extraction and analysis from the research team.

Follow-up telephonic consultations were conducted every 3-6 weeks to promote exercise adherence. During these calls, the research team characterized the participants' previous activity levels and adjusted prescriptions based on individual tolerability and evolving interests. These contacts persisted until delivery, the emerge of a medical contraindication or at the participants request.

Informational posters were displayed throughout the institution to highlight the primary advantages of prenatal physical activity. These materials included a link to dedicated social media platform design specifically for this study, intended to educate patients, dispel prevalent myths such as the unsubstantiated link between exercise and miscarriage or preterm birth and provide localized information on community exercise facilities and safe home-based workout routines.

The study was conducted in accordance with the Declaration of Helsinki and applicable national regulations for healthcare research and was approved by the Ethics Committee of the Institution (PI OBS.SF.112-2023). Informed consent was obtained from all individual participants. All materials and clinical appointments were provided without any costs for the participants, and all data were collected by healthcare professionals and processed anonymously to ensure participant confidentiality.

• Study Type: Interventional
• Enrollment (Actual): 310
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Portugal
  • Coimbra District
    • Coimbra, Coimbra District, Portugal, 3004-561
      • ULSCoimbra

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Pregnant women aged 16 years or older with a confirmed diagnosis of gestational diabetes (fasting blood glucose greater than 92 mg/dL in first trimester; or values in the oral glucose tolerance test in second trimester greater than 92/180/153 mg/dL, respectively at 0 hours, 1 hour after glucose ingestion, and 2 hours after)
• Pregnant women aged 16 or older with chronic hypertension or a history of bariatric surgery and pre-pregnancy Body Mass Index (BMI) above 30Kg/m2.
• Eligibility further required consistent clinical adherence defined as attending all schedule appointments with the obstetric team without unjustified absences

Exclusion Criteria:

• multiple gestations
• risk of preterm labor
• history of premature delivery due to a non-maternal cause
• persistent vaginal bleeding
• placenta previa beyond 28 weeks' gestation
• cervical insufficiency
• any limiting systemic, respiratory or cardiovascular disease.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: women who adhere to the recommended exercise prescription; Subsequently, participants received proactive counselling on the exercise modalities most effective for their specific pathologies, including guidance on the intensity, frequency and duration required for optimal health outcomes. This intervention included information on local exercise facilities and access to digital platforms (YouTube Channel - Active Pregnancy) featuring safe, evidence-based activities tailored for pregnancy. Prescriptions were individualized, incorporating patient preferences to determine the most suitable activity types and schedules. Participants were equipped with a smartwatch to monitor physical activity, specifically tracking heart rate, step count, distance and average speed throughout the pregnancy. They were instructed to activate the device's 'training' mode at the commencement of each exercise session. Subsequently, activity data were synced to a dedicated mobile application for later extraction and analysis from the research team.	Behavioral: Physical activity plan; pregnant women who engaged in a physical activity routine previously prescribed
Placebo Comparator: women who did not adhere to the recommended exercise prescription; Pregnant women who despite the active recommendation did not adhere to the prescribed physical activity plan	Behavioral: Women who received information but did not engaged in a physical activity routine; No structured physical activity

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Controlled chronic hypertension	Chronic hypertension was categorized as poorly controlled when medication adjustments or new therapies were necessary to achieve blood pressure values below the 140/90 mmHg threshold	From date of recruitment, usually first apointment, until the date of delivery, assessed up to 32 weeks.
Glycemic control	Glycemic control was categorized as uncontrolled if pharmacological intervention was required to meet clinical targets typically defined as having more than five weekly blood glucose readings outside the recommended range (fasting plasma glucose ≥ 95 mg/dL and/or 1-hour postprandial glucose ≥ 140 mg/dL) and no association with alimentary mistakes.	From date of recruitment, usually first apointment, until the date of delivery, assessed up to 32 weeks.
Excessive weight gain	Excessive weight gain was defined according to the Portuguese Directorate General of Health (DGS) guidelines (more than 18kg for women with pre-pregnancy BMI<18.5 kg/m 2 ; more than 16kg if previous BMI between 18.5-24.9 kg/m 2 ; more than 11.5kg if previous BMI between 25-29.9 kg/m 2 ; and more than 9kg if previous BMI above 30 kg/m 2 )	From date of recruitment, usually first apointment, until the date of delivery, assessed up to 32 weeks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Preterm delivery	Preterm birth was considered if deliver occurred before 37 weeks of gestational age	Diagnosed after delivery
Low Birth weight	Low birth weight was defined as a birth weight of less than 2500g.	Data available at one point, after delivery
Pre eclampsia	Pre eclampsia was defined as a condition that pregnant women develop after 20-weeks gestational age, with new-onset hypertension, usually with accompanying proteinuria, intrauterine growth restriction or other analytic anomalies as elevated liver enzymes, low platelet count or hemolysis.	After diagnosis until delivery, up to 20 weeks.

Collaborators and Investigators

• Sponsor: Unidade Local de Saúde de Coimbra, EPE
• Investigators: Principal Investigator: Filipa M Coutinho, MD, Unidade Local de Saude de Coimbra, EPE

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2024
• Primary Completion (Actual): February 1, 2025
• Study Completion (Actual): August 1, 2025

Study Registration Dates

• First Submitted: June 19, 2026
• First Submitted That Met QC Criteria: June 24, 2026
• First Posted (Actual): July 1, 2026

Study Record Updates

• Last Update Posted (Actual): July 2, 2026
• Last Update Submitted That Met QC Criteria: June 30, 2026
• Last Verified: January 1, 2025

More Information

Terms related to this study

• Keywords: Obesity; Physical activity intervention; Gestational Diabetes; Chronic hypertension; Digital health; High-risk pregnancy; Prenatal exercise; Smartwatch monitoring
• Additional Relevant MeSH Terms: Urogenital Diseases; Endocrine System Diseases; Vascular Diseases; Cardiovascular Diseases; Nutrition Disorders; Female Urogenital Diseases and Pregnancy Complications; Metabolic Diseases; Overnutrition; Body Weight; Pregnancy Complications; Glucose Metabolism Disorders; Diabetes Mellitus; Overweight; Hypertension; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity; Diabetes, Gestational; Hypertension, Pregnancy-Induced
• Other Study ID Numbers: ULSCoimbra

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: and all data were collected by healthcare professionals and processed anonymously to ensure participant confidentiality.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No