Trunk postural demands of occupational activities of some merchant pregnant women in Benin, West Africa

Abstract

Strenuous physical work puts expectant mothers at risk of experiencing back pain during the gestational months. Pregnant women in Benin perform physically demanding occupational tasks that include the lifting and carriage of heavy loads on their heads for commercial activities. A large percentage of pregnant subjects (58%) reported having back pain episodes since the start of their pregnancy. However, the mean Oswestry score of the affected participants was relatively low with a mean score of 0.2 (SD: 0.12), on a scale form 0 to 1. An evaluation of the postural demands of the occupational activities of these women revealed that they performed on average 328 trunk flexions at angles exceeding 60°, with 66 of these flexions sustained for more than 4 s, during the average 7.9 h where trunk postures were recorded. They also spent on average 36% of the recording time at trunk flexion angles larger than 20°. These results show that the merchant pregnant women in the Porto-Novo area in Benin are at great risk for developing back disorders during pregnancy.

Practitioner Summary: Results will make a first contribution to the literature by identifying the stressful postures adopted during a typical day. The findings of this study can help in the development of preventative concepts and postural modification techniques to decrease the occurrence of back pain during pregnancy for women in Benin.

Keywords:

• Africa
• occupational activities
• trunk posture
• inclinometer
• back pain
• pregnancy

Acknowledgements

This project was funded by research grants provided by the Natural Sciences and Engineering Research Council, the Human Mobility Research Centre and the International Society of Biomechanics travel grants program. We would also like to thank the midwife at the local maternity center and Ganiath for their tremendous help in the recruiting phase of this project as well as the numerous students at the INJEPS who helped to make things run smoothly in the laboratory.