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FM2.01.02 VIRAL INFECTIONS IN PREGNANCY GC G Clerici, R Luzietti, Center of Reproductive and Perinatal Medicine, University of Perugia, Perugia, Italy

Maternal viral infections can be transmitted and potentially affect the fetus during pregnancy and it is therefore important to try to prevent and identify the occurrence of these infections in pregnancy. In many cases maternal infections during pregnancy occur without specific symptoms or can even be asymptomatic. The clinical diagnosis is therefore rarely helpful. Viral infections stimulate production of specific antibodies but not always provide immunity and reinfection with consequent fetal transmission can occur. The risk of fetal compromise is, however, lower in recurrent infections. Ideally immune status should be assessed before conception to be able to identify seroconversion in pregnancy. In practice in most cases serology tests are performed after conception. Identification of mother susceptible of infections in early pregnancy allow adequate counseling for risk factors. Early identification of maternal infection allow to institute invasive or non invasive procedures of prenatal diagnosis. In order to effectively assess fetal risk and institute appropriate management strategies, accurate knowledge of epidemiology, risk factors, natural history, rate of sequelae, methods and limitations of prenatal diagnosis and preventive and therapeutic measures need to be well known. Preventive and diagnostic program need to be balanced against cost/benefit to society considering economic but also psychological and emotional factors. It is clearly impossible to screen all fertile women, either prenatally or during gestation, for all potential infective disease that can be transmitted to the fetus. The European Association of Perinatal Medicine has issued recommendations for maternal screening for infective diseases that can be transmitted to the fetus, that are summarized as follow. To be clinically sound and cost-effective the screening should only be instituted when the following criteria are met: *Maternal disease should clearly be associated with embryonic and fetal damage when contracted during pregnancy, alternatively the pathogen must be able to induce persistent postnatal problems. *The offending micro-organism should also be frequently encountered in the patient’s environment and the possibility of contracting the infection should be high enough to justify testing. *Sensitive and specific diagnostic techniques should be available for confirmation of maternal infection in order to identify fetuses at risk of congenital infection:Prenatal diagnostic techniques should be either available or under investigation and there should also be a possibility of treating fetal infection or of protecting the infant from the consequences of his exposure to the offending agent.

FM2.02 INTRAPARTUM CARE OF THE FETUS

FM2.02.01 OVERVIEW OF FETAL MONITORING Jose M. Belizin, Guillermo Carroli, Giselle Tomasso. Latin American Center for Perinatology and Human Development, CLAP-PAHO/WHO, Montevideo, Uruguay

The evidence extracted from systematic reviews regarding the effectiveness of electronic antepartum or intrapartum fetal monitoring are not able to show any benefit of their use on maternal and infant outcome and even in some outcomes harmful effects. However, it is worthwhile to recognise that the pioneering studies of Dr Caldeyro-Barcia and his group on maternal-fetal monitoring implied a relevant achievement in the knowledge of labour and fetal physiology and consequently giving basis for an appropriate management of labour. These achievements have represented an important improvement on fetal survival and neonatal condition at birth. Then some questions arise: should we continue with the use of antepartum fetal electronic monitoring as a diagnostic method as well with the use of continuous electronic intrapartum fetal monitoring ? Or only should we use the knowledge about physiology of labour to a better management of labour without any record of fetal heart rate ? A first reaction to these questions would come from obstetricians living in countries having no peer judgement of medical practices. Any litigation of a death or damaged baby will be condemned if electronic fetal monitoring was not performed. But in the other hand the literature shows that almost all the electronic fetal monitoring records have some ominous patterns without any association with fetal-neonatal health and

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also a high degree of disagreement among different observers on the same record tracing. In view of the available evidence we propose the following: a) for antepartum: fetal monitoring only should be used in the context of large sized and methodologically sound randomised controlled trials until further evidence will be available; b) for intrapartum: in settings where fetal monitoring is in place, a joint decision must be taken with the woman in labour, about which diagnostic tool should be used after an explanation of the advantages and disadvantages of each method (Electronic fetal monitoring and intermittent clinical auscultation), in settings where electronic fetal monitoring are not available, no effort should be put in purchasing them and women in labour should be accompanied and clinically monitored, preferably by nurses or midwifes giving continuous support to the woman in labour.

FM2.02.02 NEW METHODS OF FETAL MONITORING A.Chang, Prince of Wales Hospital, Shatin, N.T., Hong Kong

New methods of fetal monitoring can be put into one of three categories. Firstly the design and development of non-penetrating fetal probes. Secondly, the acquisition of new physiological signals, either chemical or electrical, or enhancement of known signals to allow measurement of additional parameters. Lastly, the integration of these new or existing signals into a decision support model to aid management and understanding of fetal adaptation mechanisms during the intrapartum period. Research and developments in the area of physiological signal acquisition has largely been in tandem with advances in material and sensor technology, and signal processing techniques over the past two decades. This has resulted in the design of a number of probes for both clinical and research use which can now be placed on the fetal skin surface, allowing physiological signals such as the maternal and fetal temperature, fetal blood oxygenation levels, fetal electrocardiogram waveform component assessment and determination of labour progress to be investigated. To date none of these new signals has been successfully introduced into routine clinical practice as either a direct replacement or supplement ot the monitoring of fetal heart rate changes. The increasing processing power of modern computers will inevitably lead to the greater use of artificial intelligence as a means of providing real time interpretation and analysis of fetal condition during the intrapartum period. The initial research effort in this area has attempted to derive and establish algorithms to overcome inconsistencies in human interpretation of parameters such as fetal heart rate and contractions. A consistent and precise interpretation would allow objectively determination of the extent of the correlation between abnormal pattern changes and adverse outcomes. Future work in this area is likely to focus on the integration of curent and future physiological and clinical measurements into expert systems using either coventional probability based techniques or non-linear decision techniques such as neural networks.

FM2.02.03 COMPUTERISATION OF THE CTG K. Greene, Derriford Hospital, Plymouth, United Kingdom

In the UK and USA there is increased public and political attention focused on medical error. In the developed world interpretation of the cardiotocogram (CTG) in the management of labour is a major problem. The UK Confidential Enquiry into Stillbirths and Deaths in Infancy found that 75% of deaths associated with labour could be attributed to human error and most of these were related to interpretation of the CTG. Such data emphasises that CTG instruments are merely recorders of the fetal heart rate and uterine activity; the clinicians remain the monitors. This requires experience, knowledge, expertise and attention. The use of conventional computer techniques has not proved successful for these provide little more than feature extraction with novel presentation of this data. This information still requires interpretation by the experienced clinician in the context of the particular labour. Expert systems, however, can interpret processed data ‘intelligently’ and in context. Over the past 10 years my group in Plymouth have been working on the use of intelligent systems as decision support tools for the management of labour. The knowledge base and inference engine have been carefully validated in 3 separate studies: