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Respiratory muscle strength: comparison between primigravidae and nulligravidae
Andrea Lemos1, Ariani Impieri Souza, Armele Dornelas de Andrade
1Professor Fernando Figueira Institute of Comprehensive Medicine, Recife, Brazil. lemosandrea@bol.com.br
Summary
Respiratory pressures, maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP), remain stable and comparable between pregnant women (primigravidae) and non-pregnant women (nulligravidae) aged 20-29. This study found no significant differences in respiratory muscle strength during early pregnancy.
Area of Science:
- Physiology
- Obstetrics
- Respiratory Medicine
Background:
- Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) are key indicators of respiratory muscle strength.
- Understanding respiratory function during pregnancy is crucial for maternal and fetal health.
- Previous research has not extensively compared MIP and MEP in primigravidae and nulligravidae within a specific age group.
Purpose of the Study:
- To compare MIP and MEP in primigravidae and nulligravidae aged 20-29.
- To assess the influence of pregnancy on respiratory muscle strength.
- To determine correlations between respiratory pressures, chronological age, and gestational age.
Main Methods:
- 120 low-risk primigravidae and 40 nulligravidae (20-29 years) were recruited.
- MIP and MEP were measured using a digital manometer.
- Student's t-test and multiple linear regression were employed for statistical analysis.
Main Results:
- Mean MIP values were 88.50 ± 16.52 cmH₂O in primigravidae and 94.22 ± 22.63 cmH₂O in nulligravidae (p=0.08).
- Mean MEP values were 99.76 ± 18.19 cmH₂O in primigravidae and 98.67 ± 20.78 cmH₂O in nulligravidae (p=0.75).
- Gestational age and chronological age did not significantly correlate with MIP or MEP, nor did they differ between groups.
Conclusions:
- Respiratory pressures (MIP and MEP) are stable in primigravidae during early pregnancy.
- No significant differences in respiratory muscle strength were observed between primigravidae and nulligravidae in the 20-29 age bracket.
- Pregnancy, within this age group and sample, does not appear to significantly alter maximal respiratory pressures.
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