Journal of Novel Physiotherapies
Open Access

Pregnancy is a period during which the female body undergoes functional and anatomical alterations in order to nurture and accommodate the developing foetus [1]. These changes begin after conception and affect every organ and system in the body. These changes are mechanisms that the body has adapted to meet the increased metabolic demands of the mother and fetus and to ensure adequate uteroplacental circulation for fetal growth and development [2]. These changes include hormonal, musculoskeletal, circulatory, respiratory and other systems [3].

The respiratory physiology changes during pregnancy occur due to structural changes in the chest wall and abdominal compartments as a consequence of hormonal changes, enlarging uterus and elevated diaphragm these changes include, breathlessness (dyspnea), chest increases in size, increase in the amount of air breathed in and out, decrease in amount of air the lungs can handle and increase in oxygen use. The enlarging uterus results in a maximum of 2.1 cm increase in transverse chest diameter on chest radiography and a maximum elevation of 4 cm in the level of the diaphragm [4]. Progesterone increases ventilation by increasing respiratory centre sensitivity to carbon dioxide as a result, the tidal volume and minute ventilation is increased. It is also a respiratory stimulant [5]. Also, the total pulmonary resistance may be decreased due to relaxation of the smooth muscle in the tracheobronchial tree under hormonal influence (Wise, et al, 2006). Diffusing capacity of the lungs for carbon monoxide remains normal or decreases during the second half of pregnancy. As pregnancy progresses, there will be an increase in the respiratory demands of the body. According to a study, an estimated 60–70% of women experience shortness of breath (dyspnea) during pregnancy [6].

The level of oestrogen and progesterone effects changes that occur in the vascular system, peripheral vasodilatation and resultant decrease in systemic vascular resistance (SVR) begin to occur by 8th week of gestation [2]. Cardiac output (CO) increases in order to maintain the increase in blood pressure [4]. In early pregnancy, this increase in CO is achieved by an increase in heart rate (HR) by 15–25% followed by an increase in stroke volume (SV) by 20–30% [7]. Blood volume increases, beginning from 6 to 8 weeks of gestation to reach a maximum increase of about 20% by mid-third trimester [8]. Cardiac output, pulmonary blood flow, and circulating blood volume are all increased during pregnancy due to increased metabolic demands. Pregnant women are likely to exhibit sedentary behaviors and be physically inactive, owing to their need to adjust to considerable physiological and psychological changes during pregnancy [9].

Some studies showed that only 15.8% proportion of pregnant women appeared to exhibit a physical activity level that met the recommended guidelines [10]. According to national surveys, nearly twice as many U.S. women are sedentary during pregnancy compared to the national average among U.S. adults[11]. The level of physical activity reported in the studies from Africa was low [12,13]. Also, Adeniyi et al [12] reported that about half of the participants were classified as sedentary based on their performance on the Pregnancy Physical Activity Questionnaire (PPAQ) in a study to assess physical activity and energy expenditure in Ibadan pregnant women.

Figure 1: One of the participant using the incentive spirometer.

Pregnant women who are involved in physical activity, tends to be of lower duration, frequency, and intensity relative to prepregnancy levels. A previous study in the United States showed that only 32% of pregnant women exhibited physical activity levels that were able to meet the physical activity guidelines during early pregnancy, while this number was reduced to 12% by late pregnancy [14,15]. Some women also believed that physical activity is risky during pregnancy to the fetal and maternal health. For example, many pregnant women expressed concerns on the potential harm of physical activity to the fetus.

Physical activity during pregnancy has a lot of benefits on the physical health of pregnant women. Streuling et al [16] demonstrated that pregnant women involved in physical activity are less likely to exhibit excessive gestational weight gain [16]. Physical activities in pregnant women also have benefits on the growing foetus, they include decreased resting fetal heartrate [17], improvement in the viability of the placenta, and increased amniotic fluid levels [18]. A study has also shown the benefits of physical activities during pregnancy, some of these benefits include a decreased risk of the following; preeclampsia, gestational hypertension, gestational diabetes (for example 30% reduction in risk), excessive gestational weight gain, delivery complications, postpartum depression, newborn complications, etc. [19]. Physical activity during pregnancy was associated with a reduction of instrumental deliveries [20]. Physically active pregnant women are more likely to perceive themselves to achieve a better health status than sedentary women, and they have a lower risk of developing perinatal depression [1]. Moreover, there are safe forms of exercises that improve physical activity in pregnancy such as Aerobic exercise, progressive resistive strengthening exercises, stretching exercises and breathing exercises [21].

Breathing and ventilatory training are fundamental interventions that can be administered to pregnant women. These can be performed in different forms including; diaphragmatic breathing, segmental breathing, inspirative resistance training, mechanical breathing (incentive spirometry), pursed lip breathing, glossopharyngeal breathing and deep breathing [22]. Mechanical breathing device such as the incentive spirometry (IS) has been introduced into clinical practice and encourages the patient to take long, slow deep breath mimicking natural sighing and also provides a visual positive feedback [23]. Incentive spirometers are available either by volume of inspiration (volume-oriented) or flow rate (flow-oriented). Incentive spirometry is also a machine that promotes deep breathing and helps to inflate collapsed alveoli, thus improving lung functions [24]. The use of the incentive spirometer in inspiratory muscle training has been shown to maintain or increase inhaled lung volume, prevent lung infection after surgery, and improve sputum expectoration.

Breathing exercises has been proven by many studies to have many benefits on the lungs and respiratory system, some of these benefits include; helps the woman stay calm and de-stress, reduces anxiety, aids relaxation, helps generate more needed oxygen for the body, reduces blood pressure, reduces heart rate and generally increases lung capacity [5,22]. Pregnant women may have challenges with respiration during the second and third trimesters, and the tendency of dyspnea, breathing exercise is encouraged. This ensures a steady intake of oxygen as well as prepares the woman for the need to maintain uniform and rhythmic breathing, relaxed abdominal, low chest breathing skills improve ventilation and enhance relaxation during pregnancy, labour, and postpartum. A number of studies using interventions that include breathing exercise as a component have demonstrated significant reductions in blood pressure in pregnant women post-intervention. Breathing exercise can also strengthen the muscles of the neck and chest, including the diaphragm and muscles between the ribs that work together to aid respiration [22].

The experience of pregnancy can involve significant psychological, physiological, social and behavioural changes, which can influence a woman's engagement with physical activities [18]. And several studies have shown that physical inactivity during pregnancy predisposes the women to complications such as risk of pre-eclampsia, gestational hypertension, gestational diabetes, postpartum depression and dyspnea [25]. Studies has shown that most pregnant women live sedentary lifestyles and there is a decrease in their level of physical activity especially in their third trimester, which might predispose both the mother and foetus to some complications, and can also affect the process of delivery [26,12,14]. And many researcher has shown that breathing exercises has a lot of benefits on the pregnant women, as it has positive effects on various systems in the body, including their respiratory and cardiovascular system. But the study done on the effect of breathing exercises using incentive on pregnant women and how it affects their level of physical activities is scarce. It was therefore imperative to study the effect of breathing exercise using incentive spirometer on the level of physical activity among pregnant women, hence this study.

Methods

50 participants who were at their 3rd semester of pregnancy (25 experimental and 25 control) were pulposively recruited for this experimental study. Ethical approval was obtained from the Ethics and Research committee and informed consent of participants was secured from each participant. the participants were randomized into Control (A)and experimental group (B) with tossing of coin. Group A used incentive spirometer while in group B did not, PA was measured for both group with IPAC. The Data were collected at pre baseline, 3rd and 6th week of intervention. Alpha level was set at p<0.05.

Results

Socio demographic data of participants

From this study, 2(4%) of the participants were less than 20 years of age and 98% of them were between the age range of 21-40. 2(4%) of the participants are students, 39(78%) work in private organizations and 9(18%) are civil servants (Table 1).

Table 1: Sociodemographic characteristic of the participants.

Repeated measure ANOVA of comparison of the level of physical activity in the control group

There is a significant difference in level of physical activity across the baseline, 3rd week and the 6th week in the control group (p= 0.00) (Table 2).

Table 2: Independent t- test of comparison of their level of physical activity between control and experimental groups.

Independent t test of comparison of the level of physical activity between control and experimental group

There was significant difference in the level of physical activity at the baseline and 6th week between the control and experimental group (p= 0.001), but there was no significant difference at the 3rd week (p= 0.151) (Table 3).

Table 3: Repeated measure ANOVA of comparison of level physical activity across baseline, 3rd And 6th week in control group N= 25.

Repeated measure ANOVA of comparison of the level of physical activity in the experimental group

There is a significant difference in level of physical activity across the baseline, 3rd week and the 6th week in the experimental group (p= 0.00) (Table 4).

* = level of significance set at (<0.05)
Table 4: Repeated measure ANOVA of comparison of level physical activity across baseline, 3rd And 6th week in the experimental group N= 25.

Repeated measure ANOVA of respiratory capacity across baseline, 3rd and 6th week in the experimental group

There was also significant difference of respiratory capacity across baseline, 3rd week and 6th week in the experimental group (p= 0.000) (Table 5).

Keys * =significance (<0.05)
Table 5: Repeated ANOVA of respiratory capacity of the experimental group.

Pearson correlation of the relationship between the respiratory capacity and physical activity at the experimental group

There was also significant relationship of the respiratory capacity and the level of physical activity of the pregnant women (p= 0.04) (Table 6).

Table 6: Pearson correlation of the relationship between respiratory capacity and physical activity.

Discussion

In this study, it was observed that 48(98%) of the women were within the age range of 21- 40. This is similar to Gossett [27] who revealed that risky range of maternal age to bear babies is 20-30 years and on the other side, people perceive they should postpone pregnancy [27]. Women’s mean age of first-time pregnancy increased from 21 to 25 years in the 40 years after 1970, with a decrease of mothers younger than 20 years of age, and a ssensible increase of those older than 35 [28]. In UK the average age of mothers in 2013 increased to 30.0 years, compared with 29.8 years in 2012 . The over-35’s now have the fastest growing birthrates and women having babies in their 40’s have more than doubled in ten years [29]. Teen pregnancies are a risk for both women and offspring and should be discouraged; but they are a minority [30].

There was significant difference in the level of physical activity at the control group across the baseline, 3rd and 6th week. There was also a significant difference in the level of physical activity at the experimental group across the baseline, 6th and third week. A study by Artal in 2015 showed that physical inactivity and excessive weight gain have been recognized as independent risk factors for maternal obesity and related pregnancy complications, including gestational diabetes mellitus (GDM) [31]. Concerns that regular physical activity during pregnancy may cause miscarriage, poor fetal growth, musculoskeletal injury, or premature delivery have not been substantiated for women with uncomplicated pregnancies [32]. In the absence of obstetric or medical complications or contraindications, physical activity in pregnancy is safe and desirable, and pregnant women should be encouraged to continue or to initiate safe physical activities. Most of the studies addressing fetal response to maternal exercise have focused on fetal heart rate changes and birth weight. Studies have demonstrated minimum to moderate increases in fetal heart rate by 10–30 beats per minute over the baseline during or after exercise [33]. Three metaanalyses concluded that the differences in birth weight were minimal to none in women who exercised during pregnancy compared with controls [34]. A cohort study that assessed umbilical artery blood flow, fetal heart rates, and biophysical profiles before and after strenuous exercise in the second trimester demonstrated that 30 minutes of strenuous exercise was well tolerated by women and fetuses in active and inactive pregnant women [33]. Observational studies of women who exercise during pregnancy have shown benefits such as decreased GDM (Odds Ratio [OR] 0.103; 95% CI, 0.013–0.803) [35] cesarean birth (Relative Risk 0.69, 95% CI, 0.42, 0.82) and operative vaginal delivery and postpartum recovery time [32]. Physical activity also can be an essential factor in the prevention of depressive disorders of women in the postpartum period [36,37]. A 2017 randomized controlled trial that included 300 overweight or obese women with uncomplicated, singleton gestations at less than 13 weeks of gestation found that cycling exercises initiated in the first trimester and performed at least 30 minutes, 3 times per week until 37 weeks of gestation, significantly reduced the incidence of GDM, significantly reduced gestational weight gain at less than 25 weeks of gestation, and lowered neonatal birth weight. A study of the apparent weight reduction during water immersion in a third-trimester pregnant woman measured a mean of 82.9% of body weight, a reduction that lowers the maternal osteoarticular load due to buoyancy [38]. There may be additional benefits of aquatic exercise as well. A randomized controlled trial of an aquatic physical exercise program during pregnancy consisting of three 60-minute exercises demonstrated a greater rate of intact perineum after childbirth (OR 13.54, 95% CI, 2.75–66.56) [39]. A meta-analysis based on 62 reports assessed the evidence relating preterm delivery, low birth weight, small for gestational age, preeclampsia, and gestational hypertension to five occupational exposures (work hours, shift work, lifting, standing, and physical work load) [40].

In this study, incentive spirometer was used to improve the respiratory capacity of the pregnant women in the experimental group and there was significant increase in their respiratory capacity and level of physical activity. A study carried out in 2017 on the association of physical activity with lung function in lung-healthy German adults: results from the KORA FF4 study showed that there was a significant relationship between the lung health and level of physical activity . Also a study was carried out in 2003 to study the effects of physical activity on exercise tests and respiratory function, the results showed that physical activity had a role in maintaining cardiac and respiratory function. El-Marak by et al. carried out a study on two experimental groups of patients in order to evaluate the effects of aerobic exercise training and incentive spirometry in controlling pulmonary complications following laparoscopic cholecystectomy. The researchers concluded that aerobic exercise and incentive spirometry were beneficial in reducing the postoperative pulmonary complications after laparoscopic cholecystectomy . Kundra et al. carried out a comparative study on the effect of preoperative and postoperative incentive spirometry on the pulmonary function of fifty patients who had undergone laparoscopic cholecystectomy, Result showed that pulmonary function improvement was seen after preoperative incentive Spirometry . Also, a study carried out in 2020 by Magda et al on the effect of incentive spirometer exercise on pulmonary functions in children with spastic cerebral palsy showed significant improvements in FEV1%, FVC %, and maximal mid-expiratory flow .

Conclusion

It was concluded that the level of physical activity among pregnant women, especially in their third trimester reduced progressively in the control group while there was an improvement in the level of physical activity among the pregnant women in the experimental group. The respiratory capacity measured in volume increased progressively.

Recommendations

It is recommended that pregnant women engage more in physical activities as this has a lot of benefits for mother and their foetus. There should also be an increase in the utilization of incentive spirometer to improve respiratory capacity, as this will help increase the level of physical activity and it serves as biofeedback. However, further studies should focus on the effectiveness of the use of incentive spirometer and another respiratory equipment among pregnant women .

1. Barakat R, Pelaez M, Lopez C, Montejo R, Coteron J (2012) Exercise during pregnancy reduces the rate of cesarean and instrumental deliveries: results of a randomized controlled trial . J Matern Fetal Neonatal Med 25 : 2372-2376

Indexed at, Google Scholar, Crossref

2. Berg CJ, Callaghan WM, Syverson C, Henderson Z (2010) Pregnancy-related mortality in the United States, 1998 to 2005.Obstet Gynecol 116:1302-1309.

Indexed at, Google Scholar, Crossref

3. Rodger M, Sheppard D, Chandra E, Tinmouth A (2015) Haematological problems in obstetrics. Best Prac Res Clin Obstet Gynaecol 29:67-684.

Indexed at, Google Scholar, Crossref

4. Gaiser R, Chestnut DH, Wng CA, Tsen LC, Ngan Kee WD (2014) Chestnut’s Obstetric Anesthesia: Principles and Practice. 5th ed. Philadelphia: Elsevier Saunders. Elsvier Health Sciences pp:15–38.

Indexed at, Google Scholar

5. Renault JA , Costa-Val R, Rossetti MB (2008) Respiratory physiotherapy in the pulmonary dysfunction after cardiac surgery. Rev Bras Cir Cardiovasc 23:562-569.

Indexed at, Google Scholar, Crossref

6. Löf M (2011) Physical activity pattern and activity energy expenditure in healthy pregnant and non-pregnant Swedish women. Eur J Clin Nutr 65:1295-1301.

Indexed at, Google Scholar, Crossref

7. Mahendru AA, Everett TR, Wilkinson IB, Lees CC (2014) longitudinal study of maternal cardiovascular function from preconception to the postpartum period. J Hypertens 32:849-856.

Indexed at, Google Scholar, Crossref

8. Ducas RA , Elliott JE, Melnyk SF, Premecz S, daSilva M ,et al.(2014) Cardiovascular magnetic resonance in pregnancy: insights from the Cardiac Hemodynamic Imaging and Remodeling in Pregnancy (CHIRP) study . J Cardiovasc Magn Reson 16:1.

Indexed at, Google Scholar, Crossref

9. Downs DS, Chasan-Taber L, Evenson KR, Leiferman J, Yeo S (2012) Physical activity and pregnancy: Past and present evidence and future recommendations. Res Q Exerc Sport 83:485-502.

Indexed at, Google Scholar

10. Fazzi C, Saunders DH, Linton K, Norman JE, Reynolds RM (2017) Sedentary behaviours during pregnancy: a systematic review. Int J Behav Nutr Phys Act 14:32.

Indexed at, Google Scholar, Crossref

11. Garber CE, Blissmer, B, Deschenes MR, Franklin BA, Lamonte MJ (2011) American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise . Med Sci Sports Exerc 43:1334-1359.

Indexed at, Google Scholar, Crossref

12. Adeniyi AF, Ogwumike OO, Osinike CI (2014) Physical Activity and Energy Expenditure: Findings from the Ibadan Pregnant Women’s Survey. Afr J Reprod Health 18:117-126.

Indexed at, Google Scholar

13. Hjorth MF, Kloster S, Girma T, Faurholt-Jepsen D, Andersen G, et al.(2012) Level and intensity of objectively assessed physical activity among pregnant women from urban Ethiopia. BMC Pregnancy Childbirth 12:1-8.

Indexed at, Google Scholar, Crossref

14. Ruifrok AE, Althuizen E, Oostdam N, van Mechelen W, Mol BW ,et al.(2014) The relationship of objectively measured physical activity and sedentary behaviour with gestational weight gain and birth weight. J Pregnancy 2014.

Indexed at, Google Scholar, Crossref

15. Gaston A, Cramp A (2011). Exercise during pregnancy: A review of patterns and determinants. J Sci Med Sport 14:299–305.

Indexed at, Google Scholar, Crossref

16. Streuling I, Beyerlein A, Rosenfeld E, Hofmann H, Schulz T (2011) Physical activity and gestational weight gain: A meta-analysis of intervention trials. BJOG 118: 278-284.

Indexed at, Google Scholar, Crossref

17. Gustafson KM, May LE, Yeh HW, Million SK, Allen JJ (2012) Fetal cardiacautonomic control during breathing and non-breathing epochs: Theeffect of maternal exercise. Early Hum Dev 88:539-546.

Indexed at, Google Scholar, Crossref

18. San Juan Dertkigil M, Cecatti JG, Sarno MA, Cavalcante SR, Marussi EF (2007) Variation in the amniotic fluid index following moderate physical activity in water during pregnancy. Acta Obstet Gynecol Scand 86:547-552.

Indexed at, Google Scholar, Crossref

19. Davenport M, Marchand AA, Mottola MF (2019) Exercise for the prevention and treatment of low back, pelvic girdle and lumbopelvic pain during pregnancy: a systematic review and meta-analysis. Br J Sports Med. 53:90-98.

Indexed at, Google Scholar, Crossref

20. Dipietro L, Evenson KR, Bloodgood B (2019) Benefits of physical activity during pregnancy and postpartum: an umbrella review. Med Sci Sports Exerc 51:1292-1302.

Indexed at, Google Scholar, Crossref

21. Jensen D, Duffin J, Lam YM (2008) Physiological mechanisms of hyperventilation during human pregnancy. Respir Physiol Neurobiol 161: 76-86.

Indexed at, Google Scholar, Crossref

22. Agostini P, Singh S (2009) Incentive spirometry following thoracic surgery: what should we be doing? Physiotherapy 95:76-82.

Indexed at, Google Scholar, Cross ref

23. Davies GA L, Wolfe LA, Mottola MF, MacKinnon C (2003) Joint SOGC/CSEP clinical practice guideline: Exercise inpregnancy and the postpartum period. Can J Appl Physiol 28: 330-341

Indexed at, Google Scholar, Crossref

24. Gaston A, Cramp A (2011) Exercise during pregnancy: A review of patterns and determinants. J Sci Med. Sport 14:299-305.

Indexed at, Google Scholar, Crossref

25. Gossett DR, Nayak S, Bhatt S, Bailey SC (2013) What do healthy women know about the consequences of delayed childbearing? . J Health Commun 18 (Suppl 1):118–28.

Indexed at, Google Scholar, Crossref

26. Goisis A, Sigle-Rushton W (2014) Childbearing postponement and child well-being: a complex and varied relationship? . Demography 51:1821–41.

Indexed at, Google Scholar, Crossref

27. Artal R (2015) The role of exercise in reducing the risks of gestational diabetes mellitus in obese women . Best Pract Res Clin Obstet Gynaecol 29: 123-132.

Indexed at, Google Scholar, Crossref

28. Price BB, Amini SB, Kappeler K (2012) Exercise in pregnancy: effect on fitness and obstetric outcomes-a randomized trial . Med Sci Sports Exerc 44: 2263-2269.

Indexed at, Google Scholar, Crossref

29. Szymanski LM, Satin AJ (2012) Exercise during pregnancy: fetal responses to current public health guidelines . Obstet Gynecol 119: 603-610.

Indexed at, Google Scholar, Crossref

30. Kramer MS, McDonald SW (2006) Aerobic exercise for women during pregnancy. Cochrane Database Syst Rev 19(3):CD000180

Indexed at, Google Scholar, Crossref

31. Cordero Y, Mottola MF, Vargas J, Blanco M, Barakat R (2015) Exercise is associated with a reduction in gestational diabetes mellitus . Med Sci Sports Exerc 47: 1328-1333 .

Indexed at, Google Scholar, Crossref

32. Kolomanska-Boguck D, Mazur-Bialy Al (2019) Physical Activity and the Occurrence of Postnatal Depression-A Systematic Review . Medicine (Kaunas) 55:560.

Indexed at, Google Scholar, Crossref

33. Nakamura A, van der Waerden J, Melchior M, Bolze C, El-Khoury F, et al. (2019) Physical activity during pregnancy and postpartum depression: systematic review and meta-analysis . J Affect Disord 246:29-41 .

Indexed at, Google Scholar, Crossref

34. Alberton CL, Bgeginski R, Pinto SS, Nunes GN, Andrade LS, et al. (2019).Water-based exercises in pregnancy: apparent weight in immersion and ground reaction force at third trimester . Clin Biomech (Bristol, Avon) 67:148-52 .

Indexed at, Google Scholar, Crossref

35. Rodríguez-Blanque R, Sanchez-Garcia JC, Sanchez-Lopez AM, Expósito-Ruiz M (2019).Randomized clinical trial of an aquatic physical exercise program during pregnancy . J Obstet Gynecol Neonatal Nurs 48:321-331 .

Indexed at, Google Scholar, Crossref

36. Palmer KT, Bonzini M, Harris EC, Linaker C, Bonde JP (2013) Work activities and risk of prematurity, low birth weight and pre-eclampsia: an updated review with meta-analysis . Occup Environ Med 70:213-22 .

Indexed at, Google Scholar, Crossref

37. Agnes L, Stefan K, Holger S (2017) Association of physical activity with lung function in lung-healthy German adults: results from the KORA FF4 study. BMC pulmonary medicine 17:1-9.

Google Scholar

38. El-Marakby AA, Darwiesh A, Anwar E, Mostafa A, Jad A (2013) Aerobic exercise training and incentive spirometry can control postoperative pulmonary complications after laparoscopic cholecystectomy. Middle East Journal of Scientific Research 13(4):459–463.

Indexed at, Google Scholar, Crossref

39. Kundra P, Vitheeswaran M, Nagappa M, Sistla S (2010) Effect of preoperative and postoperative incentive spirometry on lung functions after laparoscopic cholecystectomy. Surgical Laparoscopy, Endoscopy and Percutaneous Techniques 20(3):170-172.

Indexed at, Google Scholar, Crossref

40. Magda YE, Dina A (2020) Effect of incentive spirometer exercise on pulmonary functions in children with spastic cerebral palsy. Egyptian Journal of Bronchology 13:716–721.

Indexed at, Google Scholar, Crossref