Ergonomic design of a physiologic birth-support system : a research thesis for the fulfilment of the degree of Doctor of Philosophy

The main theme of this study is centred on the design and evaluation of an Obstetric Body-Support System for upright childbirth that is physiologic and biomechanically efficient, besides improving the tasks of the birth attendant in the management of labour and promoting the safety and well-being of the mother and her baby. Current practices in obstetrics and consumers' expectations are not congruent. Childbirth - a physiological event is increasingly being managed as a pathological process under medical and surgical frameworks. Medicalisation has increased iatrogenic risks to both mothers and babies and is causing profound concerns. The last two decades have witnessed two major developments in maternity care moving in opposite directions - the growing dependence on obstetric technology and the increasing demand for natural birth and humanised maternity care. Consumers' demands are no longer based simply on the emotive needs for change. They are based on recent research evidence that is indicating that less technological interference in childbirth is better than more. The posture adopted by the mother during labour is considered to be the most important factor for the safe passage of the foetus through the birth canal. There is Biblical and historical evidence that the natural posture adopted by women during childbirth has always been in some form of the upright position - sitting, squatting, kneeling and standing. The supine position for delivery facilitates the management of labour, but it has no established benefit for the maternal mother and the foetus. Many physiological disadvantages that adversely affect maternal well-being and foetal oxygenation are associated with the supine position. In contrast, the upright posture for childbirth has been found to be more beneficial to the mother and foetus. The advantages of the upright posture for labour include: taking advantage of gravitational forces to promote foetal descent; preventing compression of the aorta, inferior vena cava and umbilical cord; increasing the size of the pelvic inlet; promoting more effective bearing-down effort and promoting more efficient contraction. In terms of psychological responses, labouring in the seated position has been found to promote active participation, control and emotional satisfaction. This study examined some of these issues from an ergonomic perspective for the design and evaluation of an Obstetric Body-Support System that is compatible with the physiology of childbirth and the management of labour in current hospital settings. Antenatal and postnatal user trials were conducted to evaluate the new Obstetric Body-Support System. Responses from birth attendants and childbearing women for the new System were both positive and encouraging, indicating acceptance, system compatibility and design viability. The changing trend in childbirth demands solutions that are difficult to find in traditional maternity care and practice. The answer is in natural birth - where the woman's enormous psychological, physiological and biomechanical capabilities are relied upon to give birth spontaneously - without technological intervention. Ergodesign - a new hybrid interdisciplinary technology was conceived to design and evaluate the Obstetric Body-Support System that supports and facilitates natural childbirth in the upright position. It is argued that the use of ergonomics and design as separate disciplines militates cohesive design thinking and the creative processes. Besides the symbiotic aspects of ergodesign, the truly interdisciplinary attributes become an effective and synergistic design tool, that is more powerful than conventional approaches of applying ergonomics and design as separate disciplines. The ergodesigner as a scientist, designer as well as a change-agent played a vital role in solving the intricate human-equipment-environmental problems in the management of labour and childbirth in hospital systems. The application of ergonomics to improve childbirth is a complex task, requiring full participation from childbearing women, midwives and obstetricians. They contributed significantly by enlightening the ergodesigner with an "insight" surrounding labour and childbirth, and were involved in the development of body-support concepts, appraisals of mock-ups and evaluations of the prototype Obstetric Body-Support System. A programme of further work is planned to evaluate the clinical aspects of the maternal woman and the baby before conclusion can be drawn on the safety of the new Obstetric Body-Support System