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Cervical ripening: introductory remarks
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References 1 Bang J, Bock TE, Trolle D. Ultrasound guided fetal intravenous transfusion for severe rhesus haemolytic disease. Br Med J 1982;1:373. 2 Bang J. Ultrasound-guided fetal blood sampling. In: Albertini A, Crosignani PF (eds.), Progress in Perinatal Medicine. Amsterdam: Excerpta Medica, 1983:223. 3 Daffos F, Capella-Pavlovsky M, Forestier F. A new procedure for pure fetal blood sampling in utero. Prenat Diagn 1983;3:271-274. 4 Daffos F. Eighth Meeting of the International Fetoscopy Group, Rotterdam, 1986. 5 De Crespigny LC, Robinson HP, Quinn M, et al. Ultrasound guided fetal blood transfusion for severe Rhesus isoimmunization. Obstet Gynecol 1985;66:529. 6 International Fetoscopy Group. The status of fetoscopy and fetal tissue sampling. Prenat Diagn 1984;4:79. 7 Hobbins, JC, Mahoney MJ. In utero diagnosis of hemoglobmopathies. Technic for obtaining fetal blood. N Engl J Med 1974;290:1065. 8 Kan YW, Valenti C, Guidotti R, et al. Fetal blood sampling in utero. Lancet 1974;i:79-80. 9 Koresawa M. Eighth Meeting of the International Fetoscopy Group, Rotterdam, 1986. 10 Monni G. Seventh Meeting of the International Fetoscopy Group, Giessen, 1985. 11 Rodeck CH, Campbell S. Sampling pure fetal blood by fetoscopy in second trimester of pregnancy. Br Med J 1978;11:728-730. 12 Rodeck CH, Nicolaides KH. Fetoscopy and fetal blood sampling. Br Med Bull 1983;39:332-337. 13 Rodeck CH, Nicolaides KH, Warsof SL, et al. The management of severe rhesus isoimmunization by fetoscopic intravascular transfusion. Am J Obstet Gynecol 1984;180:769. 14 Valenti C. Antenatal detection of haemoglobinopathies. Am J Obstet Gynccol 1973;115:851.
Cervical ripening: introductory remarks M. Thiery Gent, Belgium
Attempts to develop effective and safe methods for induction of labour cover a period of more than two centuries. It is only since the late Sixties that we have had at our disposal an almost perfect method: low amniotomy and titrated intravenous (iv.) infusion of oxytocin [5]. However, while the cervix is unfavorable, use of this method is contra-indicated because labor tends to be protracted and the incidence of cesarean section, maternal pyrexia and neonatal asphyxia is high [2]. Thus, the state of the cervix is the most important predictor of the outcome of ‘conventional’ labor induction, and the obstetrician must be familiar with the assessment of cervical readiness. Obstetricians generally prefer to use semi-quantitive evaluation of the degree of cervical ripeness by pelvic scoring, and for this purpose most of them use the Bishop score [l]. A weak point of this system is that it does not distinguish between a nulliparous and a parous cervix, and this is why global evaluation of the cervical state by an experienced physician may be more accurate. The main obstacle to effective induction of labor - the unfavorable cervix could be eliminated after Embrey reported the ripening effect of iv. infusion of prostaglandin (PG)E, in amounts insufficient to induce labor [4]. The notion that PGs are unique in that they have a dual effect on the uterus was exploited clinically by Calder, who introduced local administration of PGE, for cervical ripening in 1974 [3].
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At present, the obstetrician has at his disposal a variety of methods by which an unripe cervix can be converted speedily into a favorable one allowing him to apply the conventional induction method effectively and safely. Pre-induction cervical ripening is the subject of this session. To understand the methods used for priming the cervix one must have a basic understanding of the mechanisms underlying the physiologic ripening process. The nature of this process and the factors which control it will be discussed by Prof. Ulf Ulmsten, who is Head of the Department of Ob/Gyn at the University of Uppsala in Sweden and the man who introduced intracervical PG administration for preinduction of labor in the late Seventies [6]. Having touched on this background information, I propose to scan the methods applied to mimic the natural ripening process. References Bishop E. Pelvic scoring for elective induction. Obstet Gynecol 1964;24:266. Calder AA, Embrey MP. The Management of Labour. In: Beard R, Brudenell M, DUM P, Fairweather D, eds. London: Royal College of Obstetricians and Gynaecologists, 1975:66. Calder AA, Embrey MP, Hillier K. Extra-amniotic PGE, for the induction of labour at term. J Obstet Gynaecol Br Commonw 1974;81:39. Embrey MP. The effect of prostaglandins on the human pregnant uterus. J Obstet Gynaecol Br Commonw 1969;76:783. Tumbull A, Anderson A. Induction of labour. III. Results with amniotomy and oxytocin ‘titration’. J Obstet Gynaecol Br Commonw 1968;75:32. Ulmsten U. Aspects of ripening of the cervix and induction of labor by intracervical application of PGE, in viscous gel, Acta Obstet Gynecol Stand 1979; Suppl. 84:5.
Some physical and pharmacological aspects of cervical ripening in term pregnancy Ulf Ulmsten Department of Obstetrics and Gynaecology, Uppsala University, Akademiska S-751 85 Uppsala, Sweden
Sjukhuset,
The process of parturition might well be classified in terms of an opera where cervical ripening is the overture, delivery the grand finale and post-partal involution the epilogue. This survey will focus on the overture. Although we do not know the exact mechanisms behind onset of labour it should be emphasized that every theory or explanation of this phenomenon must involve engagement of both the myometrium and the cervix. Previously the cervix was considered as a passive inferior part of the corpus uteri but today accumulating data suggest that the cervix must be recognized to have its own active role in the parturition process. Whereas the corpus uteri or the myometrium is functionally a smooth muscle, the cervix on the other hand must be characterized as a connective tissue mass. The most important parts of the cervical connective tissue are collagen fibres surrounded by huge proteoglycan molecules, as shown in Fig. 1. This arrangement gives the
References 1 Bang J, Bock TE, Trolle D. Ultrasound guided fetal intravenous transfusion for severe rhesus haemolytic disease. Br Med J 1982;1:373. 2 Bang J. Ultrasound-guided fetal blood sampling. In: Albertini A, Crosignani PF (eds.), Progress in Perinatal Medicine. Amsterdam: Excerpta Medica, 1983:223. 3 Daffos F, Capella-Pavlovsky M, Forestier F. A new procedure for pure fetal blood sampling in utero. Prenat Diagn 1983;3:271-274. 4 Daffos F. Eighth Meeting of the International Fetoscopy Group, Rotterdam, 1986. 5 De Crespigny LC, Robinson HP, Quinn M, et al. Ultrasound guided fetal blood transfusion for severe Rhesus isoimmunization. Obstet Gynecol 1985;66:529. 6 International Fetoscopy Group. The status of fetoscopy and fetal tissue sampling. Prenat Diagn 1984;4:79. 7 Hobbins, JC, Mahoney MJ. In utero diagnosis of hemoglobmopathies. Technic for obtaining fetal blood. N Engl J Med 1974;290:1065. 8 Kan YW, Valenti C, Guidotti R, et al. Fetal blood sampling in utero. Lancet 1974;i:79-80. 9 Koresawa M. Eighth Meeting of the International Fetoscopy Group, Rotterdam, 1986. 10 Monni G. Seventh Meeting of the International Fetoscopy Group, Giessen, 1985. 11 Rodeck CH, Campbell S. Sampling pure fetal blood by fetoscopy in second trimester of pregnancy. Br Med J 1978;11:728-730. 12 Rodeck CH, Nicolaides KH. Fetoscopy and fetal blood sampling. Br Med Bull 1983;39:332-337. 13 Rodeck CH, Nicolaides KH, Warsof SL, et al. The management of severe rhesus isoimmunization by fetoscopic intravascular transfusion. Am J Obstet Gynecol 1984;180:769. 14 Valenti C. Antenatal detection of haemoglobinopathies. Am J Obstet Gynccol 1973;115:851.
Cervical ripening: introductory remarks M. Thiery Gent, Belgium
Attempts to develop effective and safe methods for induction of labour cover a period of more than two centuries. It is only since the late Sixties that we have had at our disposal an almost perfect method: low amniotomy and titrated intravenous (iv.) infusion of oxytocin [5]. However, while the cervix is unfavorable, use of this method is contra-indicated because labor tends to be protracted and the incidence of cesarean section, maternal pyrexia and neonatal asphyxia is high [2]. Thus, the state of the cervix is the most important predictor of the outcome of ‘conventional’ labor induction, and the obstetrician must be familiar with the assessment of cervical readiness. Obstetricians generally prefer to use semi-quantitive evaluation of the degree of cervical ripeness by pelvic scoring, and for this purpose most of them use the Bishop score [l]. A weak point of this system is that it does not distinguish between a nulliparous and a parous cervix, and this is why global evaluation of the cervical state by an experienced physician may be more accurate. The main obstacle to effective induction of labor - the unfavorable cervix could be eliminated after Embrey reported the ripening effect of iv. infusion of prostaglandin (PG)E, in amounts insufficient to induce labor [4]. The notion that PGs are unique in that they have a dual effect on the uterus was exploited clinically by Calder, who introduced local administration of PGE, for cervical ripening in 1974 [3].
90
At present, the obstetrician has at his disposal a variety of methods by which an unripe cervix can be converted speedily into a favorable one allowing him to apply the conventional induction method effectively and safely. Pre-induction cervical ripening is the subject of this session. To understand the methods used for priming the cervix one must have a basic understanding of the mechanisms underlying the physiologic ripening process. The nature of this process and the factors which control it will be discussed by Prof. Ulf Ulmsten, who is Head of the Department of Ob/Gyn at the University of Uppsala in Sweden and the man who introduced intracervical PG administration for preinduction of labor in the late Seventies [6]. Having touched on this background information, I propose to scan the methods applied to mimic the natural ripening process. References Bishop E. Pelvic scoring for elective induction. Obstet Gynecol 1964;24:266. Calder AA, Embrey MP. The Management of Labour. In: Beard R, Brudenell M, DUM P, Fairweather D, eds. London: Royal College of Obstetricians and Gynaecologists, 1975:66. Calder AA, Embrey MP, Hillier K. Extra-amniotic PGE, for the induction of labour at term. J Obstet Gynaecol Br Commonw 1974;81:39. Embrey MP. The effect of prostaglandins on the human pregnant uterus. J Obstet Gynaecol Br Commonw 1969;76:783. Tumbull A, Anderson A. Induction of labour. III. Results with amniotomy and oxytocin ‘titration’. J Obstet Gynaecol Br Commonw 1968;75:32. Ulmsten U. Aspects of ripening of the cervix and induction of labor by intracervical application of PGE, in viscous gel, Acta Obstet Gynecol Stand 1979; Suppl. 84:5.
Some physical and pharmacological aspects of cervical ripening in term pregnancy Ulf Ulmsten Department of Obstetrics and Gynaecology, Uppsala University, Akademiska S-751 85 Uppsala, Sweden
Sjukhuset,
The process of parturition might well be classified in terms of an opera where cervical ripening is the overture, delivery the grand finale and post-partal involution the epilogue. This survey will focus on the overture. Although we do not know the exact mechanisms behind onset of labour it should be emphasized that every theory or explanation of this phenomenon must involve engagement of both the myometrium and the cervix. Previously the cervix was considered as a passive inferior part of the corpus uteri but today accumulating data suggest that the cervix must be recognized to have its own active role in the parturition process. Whereas the corpus uteri or the myometrium is functionally a smooth muscle, the cervix on the other hand must be characterized as a connective tissue mass. The most important parts of the cervical connective tissue are collagen fibres surrounded by huge proteoglycan molecules, as shown in Fig. 1. This arrangement gives the