On Parturition and Some Related Problems of Reproduction

Abstract Not Provided

Maternal and newborn plasma oxytocin levels in response to maternal synthetic oxytocin administration during labour, birth and postpartum : a systematic review with implications for the function of the oxytocinergic system

Background: The reproductive hormone oxytocin facilitates labour, birth and postpartum adaptations for women and newborns. Synthetic oxytocin is commonly given to induce or augment labour and to decrease postpartum bleeding. Aim: To systematically review studies measuring plasma oxytocin levels in women and newborns following maternal administration of synthetic oxytocin during labour, birth and/or postpartum and to consider possible impacts on endogenous oxytocin and related systems. Methods: Systematic searches of PubMed, CINAHL, PsycInfo and Scopus databases followed PRISMA guidelines, including all peer-reviewed studies in languages understood by the authors. Thirty-five publications met inclusion criteria, including 1373 women and 148 newborns. Studies varied substantially in design and methodology, so classical meta-analysis was not possible. Therefore, results were categorized, analysed and summarised in text and tables. Results: Infusions of synthetic oxytocin increased maternal plasma oxytocin levels dose-dependently; doubling the infusion rate approximately doubled oxytocin levels. Infusions below 10 milliunits per minute (mU/min) did not raise maternal oxytocin above the range observed in physiological labour. At high intrapartum infusion rates (up to 32 mU/min) maternal plasma oxytocin reached 2–3 times physiological levels. Postpartum synthetic oxytocin regimens used comparatively higher doses with shorter duration compared to labour, giving greater but transient maternal oxytocin elevations. Total postpartum dose was comparable to total intrapartum dose following vaginal birth, but post-caesarean dosages were higher. Newborn oxytocin levels were higher in the umbilical artery vs. umbilical vein, and both were higher than maternal plasma levels, implying substantial fetal oxytocin production in labour. Newborn oxytocin levels were not further elevated following maternal intrapartum synthetic oxytocin, suggesting that synthetic oxytocin at clinical doses does not cross from mother to fetus. Conclusions: Synthetic oxytocin infusion during labour increased maternal plasma oxytocin levels 2–3-fold at the highest doses and was not associated with neonatal plasma oxytocin elevations. Therefore, direct effects from synthetic oxytocin transfer to maternal brain or fetus are unlikely. However, infusions of synthetic oxytocin in labour change uterine contraction patterns. This may influence uterine blood flow and maternal autonomic nervous system activity, potentially harming the fetus and increasing maternal pain and stress

Maternal and newborn plasma oxytocin levels in response to maternal synthetic oxytocin administration during labour, birth and postpartum – a systematic review.

This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativeco mmons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the dataBackground: The reproductive hormone oxytocin facilitates labour, birth and postpartum adaptations for women and newborns. Synthetic oxytocin is commonly given to induce or augment labour and to decrease postpartum bleeding. Aim: To systematically review studies measuring plasma oxytocin levels in women and newborns following maternal administration of synthetic oxytocin during labour, birth and/or postpartum and to consider possible impacts on endogenous oxytocin and related systems. Methods: Systematic searches of PubMed, CINAHL, PsycInfo and Scopus databases followed PRISMA guidelines, including all peer-reviewed studies in languages understood by the authors. Thirty-fve publications met inclusion cri teria, including 1373 women and 148 newborns. Studies varied substantially in design and methodology, so classical meta-analysis was not possible. Therefore, results were categorized, analysed and summarised in text and tables. Results: Infusions of synthetic oxytocin increased maternal plasma oxytocin levels dose-dependently; doubling the infusion rate approximately doubled oxytocin levels. Infusions below 10 milliunits per minute (mU/min) did not raise maternal oxytocin above the range observed in physiological labour. At high intrapartum infusion rates (up to 32mU/ min) maternal plasma oxytocin reached 2–3 times physiological levels. Postpartum synthetic oxytocin regimens used comparatively higher doses with shorter duration compared to labour, giving greater but transient maternal oxytocin elevations. Total postpartum dose was comparable to total intrapartum dose following vaginal birth, but post-caesarean dosages were higher Newborn oxytocin levels were higher in the umbilical artery vs. umbilical vein, and both were higher than maternal plasma levels, implying substantial fetal oxytocin production in labour. Newborn oxytocin levels were not further elevated following maternal intrapartum synthetic oxytocin, suggesting that synthetic oxytocin at clinical doses does not cross from mother to fetus. Conclusions: Synthetic oxytocin infusion during labour increased maternal plasma oxytocin levels 2–3-fold at the highest doses and was not associated with neonatal plasma oxytocin elevations. Therefore, direct efects from synthetic oxytocin transfer to maternal brain or fetus are unlikely. However, infusions of synthetic oxytocin in labour change uterine contraction patterns. This may infuence uterine blood fow and maternal autonomic nervous system activity, potentially harming the fetus and increasing maternal pain and stress.publishedVersio

Maternal and newborn plasma oxytocin levels in response to maternal synthetic oxytocin administration during labour, birth and postpartum - a systematic review with implications for the function of the oxytocinergic system

BackgroundThe reproductive hormone oxytocin facilitates labour, birth and postpartum adaptations for women and newborns. Synthetic oxytocin is commonly given to induce or augment labour and to decrease postpartum bleeding.AimTo systematically review studies measuring plasma oxytocin levels in women and newborns following maternal administration of synthetic oxytocin during labour, birth and/or postpartum and to consider possible impacts on endogenous oxytocin and related systems.MethodsSystematic searches of PubMed, CINAHL, PsycInfo and Scopus databases followed PRISMA guidelines, including all peer-reviewed studies in languages understood by the authors. Thirty-five publications met inclusion criteria, including 1373 women and 148 newborns. Studies varied substantially in design and methodology, so classical meta-analysis was not possible. Therefore, results were categorized, analysed and summarised in text and tables.ResultsInfusions of synthetic oxytocin increased maternal plasma oxytocin levels dose-dependently; doubling the infusion rate approximately doubled oxytocin levels. Infusions below 10 milliunits per minute (mU/min) did not raise maternal oxytocin above the range observed in physiological labour. At high intrapartum infusion rates (up to 32 mU/min) maternal plasma oxytocin reached 2-3 times physiological levels.Postpartum synthetic oxytocin regimens used comparatively higher doses with shorter duration compared to labour, giving greater but transient maternal oxytocin elevations. Total postpartum dose was comparable to total intrapartum dose following vaginal birth, but post-caesarean dosages were higher.Newborn oxytocin levels were higher in the umbilical artery vs. umbilical vein, and both were higher than maternal plasma levels, implying substantial fetal oxytocin production in labour. Newborn oxytocin levels were not further elevated following maternal intrapartum synthetic oxytocin, suggesting that synthetic oxytocin at clinical doses does not cross from mother to fetus.ConclusionsSynthetic oxytocin infusion during labour increased maternal plasma oxytocin levels 2-3-fold at the highest doses and was not associated with neonatal plasma oxytocin elevations. Therefore, direct effects from synthetic oxytocin transfer to maternal brain or fetus are unlikely. However, infusions of synthetic oxytocin in labour change uterine contraction patterns. This may influence uterine blood flow and maternal autonomic nervous system activity, potentially harming the fetus and increasing maternal pain and stress

Studies on oxytocinase activity in human pregnancy

Our knowledge of the endocrine functions of the pituitary gland is comparatively recent* Text-books of physiology published in the late 19th century (e.g* Michael Post Text-Book of Physiology, 1891 edition) gave a good histological description of the gland, emphasised its ductless nature, but could attribute no definite function to it. The first evidence suggesting any function for the ft pituitary body was presented by Oliver and 0chafer in 1895* They observed that extracts from the whole pit¬ uitary gland had a pressor activity when injected intra¬ venously into the anaesthetised dog. Howell (1898) showed that the substance responsible for this pressor action of pituitary extracts was obtainable only from one part of the organ, and rather surprisingly, only from its posterior, neural lobe. At the time this appeared to be quite an anomalous finding, as the main glandular structures were known to be localised to the anterior lobe of the pituitary

Studies in physiology

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Electrical activity in the brain stem of cats during eserine perfusion of the cerebral ventricles. J. Physiol. 163: 11P. • • Abrahams, V. C. 1962. Histochemical localization of cholinesterases in some brain stem regions of the cat. J. Physiol. 165: 55P. • • Abrahams, V. C., and Langworth, E. P. 1963. Interactions between evoked potentials and background electrical activity in the hypothalamus of the cat. J. Physiol. 167: 24-25P. • • Abrahams, V. C., Langworth, E. P., and McDonald, M. 1962. Interactions between evoked potentials and background electrical activity in the brain stem of the cat. Its effect on 'computer averaging'. J. Physiol. 168: 12-13P. • • Abrahams, V. C., and Edery, H. 1964. Brain stem electrical activity and the release of acetylcholine. Progr. in Brain Res. 6_: 26-36. Bargmann, W. , and Schade, J. P., eds. Elsevier Publishing Co., Amsterdam, 1964. • • Abrahams, V. C., Hilton, S. M., and Zbrozyna, Z. 1964. The role of active muscle vasodilatation in the alerting stage of the defence reaction. J. Physiol. 171: 189-202. • • Abrahams, V. C., Langworth, E. P., and Theobald, G. W. 1964. Potentials evoked in the hypothalamus and cerebral cortex by electrical stimulation of the uterus. Nature 203: 654-656. • • Abrahams, V. C., and Langworth, E. P. 1965. A note on the use of computer averaging in the assessment of centrally acting drugs. Proc. 3rd Hungarian Conf. for Therapy & Pharm. Res., 204-209. • • Williams, R. L., and Abrahams, V. C. 1965. Patterns of circulatory change elicited by electrical stimulation of the medulla in chloralosed cats. Proc. Can. Fed. Biol. Soc. 8_: 21. • • Abrahams, V. C., and Mcintosh, J. 1965. Synchronous potentials evoked in widespread brain stem regions of conscious cats by visual, auditory and cutaneous stimuli. Proc. Can. Fed. Biol. Soc. 8:13. • • Abrahams, V. C., and Falchetto, S. 1966. The effect of stimulus modality and position on the discharge of units in the superior colliculus. Proc. Can. Fed. Biol. Soc. 9: 47. • • Abrahams, V. C. 1966. The form of averaged evoked potentials in the chloralosed cat and the effect of background activity. Proc. Can. Fed. Biol. Soc. 9: 47. • • Abrahams, V. C. 1966. Some factors affecting the form of averaged evoked potentials. J. Physiol. 185: 60-61P. • • Abrahams, V. C., and Falchetto, S. 1966. Patterns of unit response in the cat superior colliculi elicited by non-visual stimuli. The Physiologist 9: 128. • • Abrahams, V. C. , and Williams, R. L. 1967. Blood flow, heart rate, and blood pressure alterations elicited by direct electrical stimulation of lower brain stem. J. Physiol. 189: 58-59P. • • Abrahams, V. C. , and Langworth, E. P. 1967. The contribution of background electrical activity to the form of averaged evoked potentials in chloralose anaesthetized cats. Exp. Neurol. 18: 253-266. • • Abrahams, V. C. and Falchetto, S. 1967. Hind leg ataxia following section of a nerve to a neck extensor muscle. Proc. Can. Fed. Biol. Soc., 10: 145. • • Abrahams, V. C. 1968. Cervico-lumbar spinal interactions involving a brain pathway. Proc. Can. Fed. Biol. Soc., 11: 74. • • Abrahams, V. C., Butler, D. and Falchetto, S. 1968. A spinal-brain-spinal reflex and hind limb ataxia of cervical origin. Fed. Proc. , 27: #2. • • Abrahams, V. C., Milligan, J. V. and Falchetto, S. 1968. Determination of "significant" differences in unit discharge patterns. Proc. Can. Soc. Med. Biol. Eng. • • Abrahams, V. C. and Falchetto, S. 1968. Ataxia of the hind limbs of the cat following section of nerves to a neck extensor muscle and a possible reflex substrate. Proc. 24th Int. Congr. Physiol. Sci. • • Abrahams, V. C., Butler, D. and Daynes, J. 1969. A cortical relay site in cervico-lumbar interactions in cats. Proc. Can. Fed. Biol. Soc., 12: 55. • • Abrahams, V. C., Butler, D. and Daynes, J. 1969. Proprioceptive relays to the cerebral cortex and their significance in intraspinal organization. The Physiologist, 12: 154. • • Abrahams, V. C. 1969. Pathways involved in potentiation of lumbo-sacral reflexes by biventer cervicis nerve stimulation. Proc. Can. Physiol. Soc. • • Abrahams, V. C. and Falchetto, S. 1969. Hind leg ataxia of cervical origin and cervico-lumbar spinal interactions with a supratentorial pathway. J. Physiol. 203: 435-447. • • Abrahams, V. C. 1969. Proprioceptive projection areas of the cerebral cortex and their relation to cervico-lumbar spinal interactions. J. Physiol., 204: 82-83. • • Abrahams, V. C. and Teare, J. L. 1969. Peripheral pathways and properties of uterine afferents in the cat. Can. J. Physiol, and Pharmacol., 47: 576-577. • • Jagannthan, T., Foote, J., Abrahams, V. C., Bruce, A. W., Hetherington, R. F., Lywood, D. W. and English, C. J. 1969. A new approach to bladder evacuation: Studies in dogs. Inv. Urol., 7: 15-22. • • Abrahams, V. C. 1969. Intraspinal mechanisms in cortically mediated descending cervicolumbar reflex interactions. Can. Physiol., 1: 37. • • Abrahams, V. C. 1970. Computers in Medical Diagnosis. IEEE, Student J., 8: 35-38. • • Abrahams, V. C. 1970. Cervico-lumbar reflex interactions involving a proprioceptive receiving area of the cerebral cortex. J. Physiol., 209: 45-56. • • Abrahams, V. C. 1970. Intraspinal excitability changes during cortically mediated descending cervico-lumbar reflex interactions. Fed. Proc. 29_: #824, p.391. • • Abrahams, V. C. 1970. Individual mechanisms activated in descending spino-spinal activity in the chloralose anaesthetized cat. J. Physiol., 210: 175-176. • • Abrahams, V. C. 1971. Spino-spinal mechanisms in the chloralose anaesthetized cat. J. Physiol., 215: 755-768. • • Abrahams, V. C. 1971. Some effects on vestibulo-spinal outflow at lumbosacral levels from neck muscle afferents. J. Physiol., 215: 49-50. • • Rose, P. K. and Abrahams, V. C. 1972. Some characteristics of the neck muscle proprioceptive input to the superior colliculus of the cat. Can. Fed. Biol. Soc., 15: #732. • • Abrahams, V. C. 1972. Site of fixation in the spinal cord of the cat. Can. Fed. Biol. Soc., 1_5: #693. • • Abrahams, V. C. and Rose, P. K. 1972. Proprioceptive connections to the superior colliculi of the cat. Fed. Proc., 31: 383, #929. • • Abrahams, V. C. 1972. Neck muscle proprioceptors and a role of the cerebral cortex in postural reflexes in subprimates. Rev. Can. Biol., 31_: suppl., 115-130. • • Abrahams, V. C. 1972. Neck muscle proprioceptives and vestibulospinal outflow at lumbosacral levels. Can. J. Physiol, and Pharmacol., 50: 17-21. • • Abrahams, V. C. and Daynes, J. 1972. Fixation of inhibition of a spinal reflex by electrical stimulation of the medulla.' Soc. Neurosc., 2nd Ann. Meeting, p. 204. • • Abrahams, V. C. and Rancier, F. 1973. ATPase distribution in dorsal neck muscles of the cat. Can. J. 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Physiol. 244: 45. • • Abrahams, V. C. and Rose, P. K. 1974. Medullary projections of Gp I and II afferents from neck muscle in the cat. Soc. Neurosc., 4th Ann. Meeting, p. 111. • • Abrahams, V. C. and Rose, P. K. 1975. Projections of extraocular, neck muscle, and retinal afferents to superior colliculus in the cat: their connections to the cells of origin of the tectospinal tract. J. Neurophysiol. 38: 10-18. • • Abrahams, V. C. and Rose, P. K. 1975. The spinal course and distribution of fore and hind-limb muscle afferent projections to the superior colliculus of the cat. J. Physiol. 247: 117-130. • • Abrahams, V. C. and Rose, P. K. 1975. The effect of passive eye movement on unit discharge in the superior colliculus of the cat. Brain Research, 974 95-106. • • Abrahams, V. C. and Rose, P. K. 1975. Velocity and displacement characteristics of passive eye movements which initiate unit discharge in the superior colliculus. J. Physiol. 246: 101. • • Abrahams, V. C., Richmond, F. 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Meeting, 1976. Richmond, F. J. and Abrahams, V. C. 1976. Physiological properties of dorsal muscles of the cat neck. Can. Physiol., 7: 50. • • Anstee, G. C. B., Richmond, F. J. and Abrahams, V. C. 1976. Sensory and motor fibre spectra of neck muscle nerves in the cat. Can. Physiol., 7: 16. • • Richmond, F. J., Anstee, G. B. C., Sherwin, L., and Abrahams, V. C. 1976. Motor and sensory fibres of neck muscle nerves in the cat. Can. J. Physiol, and Pharmacol., 54: 294-304. • • Abrahams, V. C., Richmond, F. J. and Rose, P. K. 1977. Spinal and medullary projections from neck muscle afferents in the cat. J. Neurophysiol. - manuscript for submission. • • Abrahams, V. C. 1977. The motor system of the head. A short review. In press. • • Rose, P. K. and Abrahams, V. C. 1977. Tectospinal and tectoreticular cells. A comparison of their distribution within the superior colliculus and their afferent connections. J. Neurophysiol., - manuscript for submission

Anatomical and physiological studies of the vascular, nervous and muscular tissues of the mammary glands

It is not necessary to reiterate in detail the gross blood and nerve supply to the mammary glands given in Section I, Part II. The glands extend along the ventral thorax and abdomen and receive a multiple blood and nerve supply in common with the other subcutaneous tissues.The fact that many cutaneous nerves of thoracic and lumbar !origin innervate the glands, stresses the difficulty of thorough ly denervating them for experimental purposes, without actual transplantation.The multiple blood supply is understandable in the case of such a widely dispersed tissue, but it may have additional significance for maintaining the blood flow under all conditions. ,For example, it has been shown that the anastomoses within the tissue are such that it is possible for blood to reach all parts from any one main source of supply. It is conceivable that in ,certain positions of the body some of the mammary vessels,which are very superficial, might be sufficiently compressed to reduce the blood flow through them. However the vascular anastomoses mean that it is very unlikely that this would affect the total flow through the tissue as a whole.The microscopical examination of the small sblood vessels shows that, whilst the lobes have a multiple blood supply, the individual lobules do not generally receive more than one arteriole and venule. The capillaries around the alveoli form part of a complete network confined to the individual lobules but also embracing the smallest milk ducts draining them. The larger ducts also have an encircling capillary net, which is supplied at intervals by arterioles and venules, and continues right up to the mouths of the ducts, when it joins that of the skin. The largest ducts and cisterns have in addition a second layer of vessels, formed by the supplying arterioles and venules.The arteriole-venular bridges of zweifach (1939), seen in some lobules and the arterio-venous anastomoses doubtfully recorded on some of the ducts, probably serve to maintain the overall blood flow through the tissues, whilst allowing greater control of the flow through small parts of it.The significance of the venous network in the teat is not clear. It was first thought by Furstenberg (1868), Riederer (1903) and _ubeli (1916) to form a cavernous erectile tissue in the cow and that it was concerned in the flow of milk. Purstenr berg for example, thought that a cow held up her milk by holding her breath and actually obliterating the teat lumen by venous turgescence, whilst Rubeli believed that the latter was produced by vasomotor nerves. As has been shown in Section VIII, Part I and in Section IV, Part II of this thesis, it is no longer thought that the holding up of milk is an active process, but that the "letting down" is. The teat vessels have received no mention in modern theories, neither have they in the recent studies of the erection of the teat and its behaviour during milking by Peeters, Massart, Oyeart and Coussens (1948). They have shown that the smooth muscle in the nipple undergoes rhythmical contractions when it is distended, and suggested that the compression of the veins at this time aids the return of the blood to the heart

Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care

This report synthesizes evidence about innate hormonally-mediated physiologic processes in women and fetuses/newborns during childbearing, and possible impacts of common maternity care practices and interventions on these processes, focusing on four hormone systems that are consequential for childbearing. Core hormonal physiology principles reveal profound interconnections between mothers and babies, among hormone systems, and from pregnancy through to the postpartum and newborn periods. Overall, consistent and coherent evidence from physiologic understandings and human and animal studies finds that the innate hormonal physiology of childbearing has significant benefits for mothers and babies. Such hormonally-mediated benefits may extend into the future through optimization of breastfeeding and maternal-infant attachment. A growing body of research finds that common maternity care interventions may disturb hormonal processes, reduce their benefits, and create new challenges. Developmental and epigenetic effects are biologically plausible but poorly studied. The perspective of hormonal physiology adds new considerations for benefit-harm assessments in maternity care, and suggests new research priorities, including consistently measuring crucial hormonally-mediated outcomes that are frequently overlooked. Current understanding suggests that safely avoiding unneeded maternity care interventions would be wise, as supported by the Precautionary Principle. Promoting, supporting, and protecting physiologic childbearing, as far as safely possible in each situation, is a low-technology health and wellness approach to the care of childbearing women and their fetuses/newborns that is applicable in almost all maternity care settings

The chromatophore activating substance in the pituitary gland of the vertebrates

Thesis (M.A.)--Boston University This item was digitized by the Internet Archive.This paper is concerned with the color changes of the cold blooded vertebrates in which the pigment ceils of the integument are concerned. It was first thought that these pigment cells or chromatophores actually contracted and expanded, amoeba-like, during alterations of tint. Careful studies showed that in the melanophores or black pigment cells, this was not the case. Here the pigment granules migrated within the clear protoplasm of a cell with fixed boundaries. This led to a change in the nomenclature from "expansion and contraction" of the chromatophores to "dispersion and concentration of the pigment" of these cells. The variations in the position of the pigment in these tiny cells account for the color changes which can be noted with the naked eye