|Care in Normal Birth (WHO, 1996, 60 p.)|
|5. CARE DURING THE THIRD STAGE OF LABOUR|
The combined effects of oxytocics and controlled cord traction are sometimes summarized by the term active management of the third stage, as opposed to expectant or physiological management. Sometimes early clamping of the cord is included too, especially because in controlled cord traction early clamping is mandatory. However, because the main effects of this procedure relate to the newborn we shall deal with that aspect separately.
In the literature active management of the third stage compares favourably with expectant management, mainly because postpartum haemorrhage occurs less often and haemoglobin levels postpartum are higher (Prendiville et al 1988, Harding et al 1989, Begley 1990, Thigalathan et al 1993). The results with respect to the frequency of blood transfusion and manual removal of the placenta are not identical in the two largest trials, in Bristol and Dublin (Prendiville et al 1988, Begley 1990). In both trials active management resulted in more nausea, vomiting and hypertension, probably caused by the use of ergometrine.
Some remarks on these findings may be justified. Postpartum haemorrhage is defined by WHO as blood loss >= 500 ml (WHO 1990). The diagnosis is made by a clinical estimate of blood loss; such an assessment of the amount of blood often causes a significant underestimation. Apparently the definition is influenced by the fact that in large parts of the world 500 ml of blood loss (or even less) is a real threat to the life of many women, mainly because of the high prevalence of severe anaemia. Nevertheless, if meticulously measured, the mean blood loss at vaginal delivery is around 500 ml, and about 5% of women delivering vaginally lose more than 1000 ml of blood (Pritchard et al 1962, Newton 1966, De Leeuw et al 1968, Letsky 1991). In the Bristol trial (Prendiville et al 1988) 18% of the group of women with a physiological management of the third stage had blood loss >= 500 ml, and only 3% lost > 1000 ml.
In a healthy population (as is the case in most developed countries) postpartum blood loss up to 1000 ml may be considered as physiological, and does not necessitate treatment other than oxytocics. However, in many developing countries other standards may be applied. The 500 ml limit as defined by WHO should be considered an alert line; the action line is then reached when vital functions of the woman are endangered. In healthy women this usually only occurs after blood loss >1000 ml. This distinction is crucial in the light of efforts to minimise unnecessary blood transfusion and its associated risks, including HIV infection.
Definite conclusions about the value of active management of the third stage in healthy low-risk populations cannot yet be drawn. The term active management is used for a combination of various interventions with different effects and side-effects. All trials of expectant versus active management were carried out in centres where active management was the normal practice. A trial is needed in a setting where both expectant and active management are normal procedures. The occurrence of serious but rare complications (cardiac complications, eclampsia, inversion of the uterus, etc.) cannot be studied in randomized trials, but might nevertheless be of major importance if and when active management is recommended for large populations. Serious doubts are justified about the routine prophylactic use of ergometrine or a combination of oxytocin and ergometrine, and also about controlled cord traction as a routine procedure.
In conclusion, oxytocin administration immediately after delivery of the anterior shoulder, or after delivery of the infant, seems advantageous, especially in women with increased risk of postpartum haemorrhage or in women endangered by even a small amount of blood loss, for instance women with severe anaemia. Doubts remain about the combination with controlled cord traction, and about the routine application in healthy low-risk women. Recommendation of such a policy would imply that the benefits of this management would offset and even exceed the risks, including potentially rare but serious risks that might become manifest in the future. In our opinion it is too early to recommend this form of active management of the third stage for all normal low-risk deliveries, although we note the earlier recommendations made by WHO (1990, 1994c). If for various reasons active management is employed, a number of questions remain unresolved, particularly regarding the optimal timing of prophylactic oxytocin injections.