Interventionist versus expectant care for severe pre-eclampsia before term
Data are not sufficient to decide whether it is better to intervene or to apply a policy of expectant care for women with early onset of severe pre-eclampsia. Lack of human and material resources to monitor women intensively for a prolonged period may render expectant management difficult to implement in resource-poor settings.
RHL Commentary by Lombaard H, Pattinson R
1. EVIDENCE SUMMARY
The review compares the effects of a policy of interventionist care and early delivery with a policy of expectant care and delayed delivery for women with early onset of severe pre-eclampsia. The main objective of expectant management is to allow the baby more time in utero so that the risk of respiratory distress syndrome or other complications due to prematurity could be reduced. There are only two trials (totalling 133 women) included in the review, one conducted in the USA and the other in South Africa.
In the group subjected to interventionist care there was a greater incidence of hyaline membrane disease, necrotising enterocolitis and admission to intensive care compared with the expectant care group. However, fewer babies in the interventionist care group were small for gestational age. The included trials are small so the data are insufficient to draw any reliable conclusions about substantive outcomes related to maternal morbidity or mortality or perinatal morbidity or mortality.
The authors conclude that there are insufficient data to make recommendations regarding the best policy with regard to early onset of severe pre-eclampsia and that more trials with appropriate size and end points are needed.
2. RELEVANCE TO UNDER-RESOURCED SETTINGS
2.1. Magnitude of the problem
Pre-eclampsia is common with a prevalence estimated at 2.3% of all pregnancies in developing countries (1). About half the women with severe pre-eclampsia present themselves at the health centre at less than 34 weeks of gestation, with an estimated fetal weight of less than 2000 g. About half of those presenting at less than 34 weeks' gestation require delivery for either fetal or maternal reasons within 24 hours of admission to hospital. The remaining half will gain on average 9 days before delivery is indicated (2).
A survey (3) in South Africa found that in more than half of the perinatal deaths related to complications of hypertension in pregnancy the birth weight of the infant was between 1000 g and 2000 g. (This is the birth weight category in which expectant management would have its greatest impact.) Overall, hypertension contributed 39% of all perinatal deaths, but only 9% of the neonatal deaths in the 1000-2000 g birth weight category. The majority of deaths occurred before delivery. Respiratory distress was responsible for only 23% of the neonatal deaths. Hence, at best only a small proportion of deaths due to respiratory distress occurring as a result of hypertension complication would be prevented.
This modest reduction (benefit) would need to be weighed against the potential danger to the mother of prolonging the pregnancy. Complications such as abruptio placenta, HELLP (haemolysis, elevated liver enzymes and low platelets) syndrome, renal failure, convulsions, etc. have all been described in women managed expectantly. In areas where careful monitoring of the mother is possible these complications are relatively rare (4).
2.2. Applicability of the results
The studies in the systematic review are too small to make clear recommendations regarding the best policy with regard to early onset of severe pre-eclampsia. Since one of the two trials was done in a developing country (South Africa) the findings of the review would normally be applicable to resource-poor settings.
Data from the randomized controlled trials included in the review are consistent with large observational studies (4, 5, 6). One observational study of 131 women looked at expectant management of early onset pre-eclampsia at a secondary hospital (7).This study concluded that expectant management at a secondary hospital appears to be safe for mother and child, provided a scheme of intensive monitoring is applied, and if referral to a tertiary centre is possible. There was one maternal death in this study and the perinatal mortality was 44.4/1000 (for all babies > 1000 g) and 59.2/1000 for babies > 500 g. Maternal complications include; abruptio placentae, HELLP syndrome, loss of blood pressure control, severe renal impairment, eclampsia, admission to intensive care unit, pulmonary oedema and cerebrovascular incident.
2.3. Implementation of the intervention
The major problem with expectant management in developing countries is the lack of resources (human and material) to monitor the mother and fetus intensively. Expectant management requires a place where the mother can be admitted for a prolonged period of time, staff for monitoring, equipment for electronic fetal monitoring (cardiotocography), umbilical artery Doppler and laboratory facilities. The Growth Restriction Intervention Trial (GRIT) (8) showed that the combination of uterine artery Doppler and cardiotocography provided the best method to determine the timing of delivery. A more important aspect than just the number of staff available to do the monitoring is the number of dedicated and experienced staff including doctors to look after and care for these patients. Thus, expectant management should only be attempted in a tertiary-level hospital.
3. RESEARCH
Large trials are needed, especially in less developed countries, to ascertain the risk to the mother and the baby from both interventionist care and early delivery and expectant care. These studies should include all patients admitted with pre-eclampsia and not only patients after the first 24 hours. This will provide the answer regarding what percentage of patients qualify for expectant management after the first 24 hours and compare the outcomes for mother and baby in the two groups.
Sources of support: Medical Research Council of South Africa
Acknowledgements: None
References
- Villar J, Say L, Gülmezoglu AM, Merialdi M, Lindheimer MD et al. Eclampsia and pre-eclampsia: a worldwide health problem for 2000 years. Pre-eclampsia, Critchley H, MacLean A, Poston L and Walker J eds., London. RCOG Press;2003.
- Cornette J, Jeffrey B, Pattinson RC. Pre-eclampsia at the Kalafong Hospital (University of Pretoria). Retrospective study illustrating some aspects of a tertiary referral centre pre-eclampsia population in South Africa.. Proceedings of the 22nd Conference on Priorities in Perinatal Care in Southern Africa;23.
- Saving Babies 2003. Fourth perinatal care survey of South Africa. Web site: http://www.ppip.co.za/Downloads/Saving%20babies%202003.pdf;(visited on 10 Jan 2005).
- Hall DR, Odendaal HJ, Steyn DW, Grové D. Expectant management of early onset, severe pre-eclampsia: maternal outcome.. British journal of obstetrics and gynaecology 2000;107:1252–1257.
- Hall DR, Odendaal HJ, Kirsten GF, Smith J, Grové D. Expectant management of early onset, severe pre-eclampsia: perinatal outcome. British journal of obstetrics and gynaecology 2000;107:1258–1264.
- Hall DR, Odendaal HJ, Steyn DW. Expectant management severe pre-eclampsia in the mid-trimester.. European journal of obstetrics and gynaecology and reproductive biology 2001;96:168–172.
- Oettle C, Roux A, Hall D. Expectant management of early onset severe pre-eclampsia at a secondary hospital. Proceedings of the 22nd Conference on Priorities in Perinatal Care in Southern Africa;6-9.
- The Grit Study Group. A randomised trial of timed delivery for the compromised preterm fetus: short term outcomes and Bayesian interpretation. British journal of obstetrics and gynaecology 2003;110:27-32.
This document should be cited as: Lombaard H and Pattinson B. Interventionist versus expectant care for severe pre-eclampsia before term : RHL commentary (last revised: 5 August 2004). The WHO Reproductive Health Library; Geneva: World Health Organization.