Shortness of breath (dyspnea) is commonly experienced during the third trimester of pregnancy due to physiological changes affecting the respiratory system. Non-pharmacological breathing interventions are often recommended to improve breathing comfort and functional capacity in pregnant women.

This randomized controlled trial compared the effects of deep breathing exercises and volume-oriented incentive spirometry on dyspnea, functional endurance, and pulmonary function in women during the third trimester of pregnancy. Eligible participants were randomly assigned to one of two intervention groups. One group performed supervised deep breathing exercises, while the other group performed volume-oriented incentive spirometry exercises.

Outcomes were measured before and after the intervention period and included the severity of dyspnea, functional endurance, and pulmonary function parameters. The results of this study aim to provide evidence regarding the effectiveness of simple, safe, and non-invasive breathing interventions for improving respiratory outcomes during late pregnancy.

This study was a randomized controlled trial designed to evaluate and compare the effects of two non-pharmacological respiratory interventions in women during the third trimester of pregnancy. Physiological changes during pregnancy, such as diaphragmatic elevation and increased oxygen demand, can contribute to dyspnea and reduced functional endurance. Safe and effective breathing interventions may help alleviate these symptoms without pharmacological risk.

Eligible pregnant women in their third trimester who met the inclusion criteria were recruited and randomly allocated into two intervention groups using a randomization method. Participants in Group A received a structured deep breathing exercise program, which focused on slow, controlled inhalation and exhalation techniques performed under supervision. Participants in Group B received volume-oriented incentive spirometry training, which encouraged sustained maximal inspiration using a standard incentive spirometer device.

Both interventions were administered according to a predefined protocol over the study period. Outcome measures were assessed at baseline and after completion of the intervention period. Primary outcomes included the assessment of dyspnea severity. Secondary outcomes included measures of functional endurance and pulmonary function.

The study was conducted in accordance with ethical standards and received approval from the institutional ethics review committee. All participants provided informed consent prior to participation. The findings of this study are intended to contribute to evidence-based physical therapy practice by identifying effective, low-risk breathing interventions for managing dyspnea and improving respiratory function during the third trimester of pregnancy.

Inclusion Criteria:

• - Participants aged between 18 and 40 years
• Blood pressure below 140/90 mmHg
• Not pregnant
• Primigravida women
• Participants in the third trimester of pregnancy
• Able to understand and follow instructions
• Willing to participate and provide informed consent

Exclusion Criteria:

• - History of cardiovascular disorders
• History of respiratory disorders
• History of psychological disorders
• History of medical or surgical conditions involving the nose, throat, diaphragm, or lungs
• Any condition that could interfere with participation in breathing exercises or spirometry

Individual participant data will not be shared because this study was conducted as a university-based academic research project with data collected for thesis purposes. The informed consent obtained from participants did not include provisions for public data sharing, and the dataset contains sensitive personal health information. Data will be stored securely at the institution and used only for academic and research purposes in accordance with institutional ethics approval.

Outcome assessors were blinded to group allocation to reduce assessment bias. Participants and care providers were not blinded due to the nature of the interventions.