n.

死産、死産児

WordNet

(of newborn infant) showing no signs of life at birth; not liveborn; "a stillborn baby"

PrepTutorEJDIC

死産;〈C〉死産児
児んで生まれた,死産の

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/05/19 10:21:33」(JST)

wiki en

[Wiki en表示]

A stillbirth occurs when a fetus has died in the uterus. A wide variety of definitions exist.^[1] Once the fetus has died, the mother may or may not have contractions and undergo childbirth. The term is often used in distinction to live birth or miscarriage and the word miscarriage is oftentimes used incorrectly to describe stillbirths. Most stillbirths occur in full-term pregnancies.

1 Human stillbirth
- 1.1 Causes
- 1.2 Prenatal diagnosis
  - 1.2.1 Constricted umbilical cord
- 1.3 Prevention
- 1.4 Prenatal maternal treatment
- 1.5 Prevalence
2 Legal definitions of stillbirth
- 2.1 Australia
- 2.2 Austria
- 2.3 Canada
- 2.4 Germany
- 2.5 Ireland
- 2.6 United Kingdom
- 2.7 United States
3 See also
4 References
5 Further reading
6 External links

Human stillbirth [edit]

Causes [edit]

The causes of a large percentage of human stillbirths remains unknown, even in cases where extensive testing and autopsy have been performed. A rarely used term to describe these is sudden antenatal death syndrome or SADS, a phrase coined by Cacciatore & Collins in 2000.^[2]

In cases where the cause is known, some possibilities of the cause of death are:

bacterial infection
birth defects, especially pulmonary hypoplasia
chromosomal aberrations
growth retardation
intrahepatic cholestasis of pregnancy
maternal diabetes
high blood pressure, including preeclampsia
maternal consumption of recreational drugs (such as alcohol, nicotine, etc.) or pharmaceutical drugs contraindicated in pregnancy
postdate pregnancy
placental abruptions
physical trauma
radiation poisoning
Rh disease
Female Genital Mutilation^[3]

Entanglement of cord in twin pregnancy at the time of Caesarean Section

umbilical cord accidents^[4]
- "Prolapsed umbilical cord" - Prolapse of the umbilical cord happens when the fetus is not in a correct position in the pelvis. Membranes rupture and the cord is pushed out through the cervix. When the fetus pushes on the cervix, the cord is compressed and blocks blood and oxygen flow to the fetus. The mother has approximately 10 minutes to get to a doctor before there is any harm done to the fetus.
- "Monoamniotic twins" - These twins share the same placenta and the same amniotic sac and therefore can interfere with each other's umbilical cords. When entanglement of the cords is detected, it is highly recommended to deliver the fetuses as early as 31 weeks.
- Umbilical cord length - A short umbilical cord (<30 cm) can affect the fetus in that fetal movements can cause cord compression, constriction and ruptures. A long umbilical cord (>72 cm) can affect the fetus depending on the way the fetus interacts with the cord. Some fetuses grasp the umbilical cord but it is yet unknown as to whether a fetus is strong enough to compress and stop blood flow through the cord. Also, an active fetus, one that frequently repositions itself in the uterus can cause entanglement with the cord. A hyperactive fetus should be evaluated with ultrasound to rule out cord entanglement.
- Cord entanglement - The umbilical cord can wrap around an extremity, the body or the neck of the fetus. When the cord is wrapped around the neck of the fetus it is called a nuchal cord. Again, these entanglements can cause constriction of blood flow. These entanglements can be visualized with ultrasound.
- Torsion - This term refers to the twisting of the umbilical around itself. Torsion of the umbilical cord is very common (especially in equine stillbirths) but it is not a natural state of the umbilical cord. The umbilical cord can be untwisted at delivery. The average cord has 3 twists.

Sometimes a pregnancy is terminated deliberately during a late phase, for example for congenital anomaly. UK law requires these procedures to be registered as "stillbirths".^[5]

Prenatal diagnosis [edit]

It is unknown how much time is needed for a fetus to die. Fetal behavior is consistent and a change in the fetus' movements or sleep-wake cycles can indicate fetal distress.^[4] A decrease or cessation in sensations of fetal activity may be an indication of fetal distress or death, though it is not entirely uncommon for a healthy fetus to exhibit such changes, particularly near the end of a pregnancy when there is considerably less space in the uterus than earlier in pregnancy for the fetus to move about. Still, medical examination, including a nonstress test, is recommended in the event of any type of any change in the strength or frequency of fetal movement, especially a complete cease; most midwives and obstetricians recommend the use of a kick chart to assist in detecting any changes. Fetal distress or death can be confirmed or ruled out via fetoscopy/doptone, ultrasound, and/or electronic fetal monitoring. If the fetus is alive but inactive, extra attention will be given to the placenta and umbilical cord during ultrasound examination to ensure that there is no compromise of oxygen and nutrient delivery.

Constricted umbilical cord [edit]

When the umbilical cord is constricted (q.v. "accidents" above), the fetus experiences periods of hypoxia, and may respond by unusually high periods of kicking or struggling, to free the umbilical cord. These are sporadic if constriction is due to a change in the fetus' or mother's position, and may become worse or more frequent as the fetus grows. Extra attention should be given if mothers experience large increases in kicking from previous childbirths, especially when increases correspond to position changes.^[6]

Prevention [edit]

As many of the causes are unknown or untreatable, prevention is difficult. Symptoms of bacterial infection, such as from a dental abscess, in pregnant women may also include unusual periods of incoherence and symptoms of shock, and should be treated by a physician immediately. High blood pressure, diabetes and drug use should be regulated with physician's advice. Umbilical cord constriction may be identified and observed by ultrasound, if requested.

Research published in the Journal of the American Medical Association in 2011 found a number of maternal factors associated with stillbirth. Among them: being age 40 or older, having diabetes, having a history of addiction to illegal drugs, being overweight or obese, and smoking cigarettes in the three months before getting pregnant.^[7]

Prenatal maternal treatment [edit]

An in utero stillbirth does not usually present an immediate health risk to the woman and labour will usually begin spontaneously after two weeks, so the woman may choose to wait and birth the fetal remains vaginally. After two weeks, the woman is at risk of developing blood clotting problems, and labor induction is recommended at this point. In many cases, the woman will find the idea of carrying the dead fetus emotionally traumatizing and will elect to be induced. Caesarean birth is not recommended unless complications develop during vaginal birth.

Prevalence [edit]

The mean stillbirth rate in the United States is approximately 1 in 115 births, which is roughly 26,000 stillbirths each year, or on an average one every 20 minutes. In Australia,^[8] England, Wales, and Northern Ireland, the rate is approximately 1 in every 200 births, in Scotland 1 in 167. (From The National Statistical Office and other sources.) Many stillbirths occur at fullterm to apparently healthy mothers, and a postmortem evaluation reveals a cause of death in only about 40% of autopsied cases.^[9]

In developing countries, where medical care can be of low quality or unavailable, the stillbirth rate is much higher.

Legal definitions of stillbirth [edit]

Australia [edit]

In Australia any stillborn weighing more than 400 grams, or more than 20 weeks in gestation, must have its birth registered.^[10]

Austria [edit]

In Austria a stillbirth is defined as birth of a child of at least 500 g weight without vital signs, e.g. blood circulation, breath or muscle movements.

Canada [edit]

Beginning in 1959, "the definition of a stillbirth was revised to conform, in substance, to the definition of fetal death recommended by the World Health Organization." ^[11] The definition of "fetal death" promulgated by the World Health Organization in 1950 is as follows:

"Fetal death" means death prior to the complete expulsion or extraction from its mother of a product of human conception, irrespective of the duration of pregnancy and which is not an induced termination of pregnancy. The death is indicated by the fact that after such expulsion or extraction, the fetus does not breathe or show any other evidence of life, such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles. Heartbeats are to be distinguished from transient cardiac contractions; respirations are to be distinguished from fleeting respiratory efforts or gasps.^[12]

Germany [edit]

In Germany a stillbirth is defined as birth of a child of at least 500g weight without blood circulation or breath. Details for burial vary amongst the federal states.^[13]

Ireland [edit]

Since 1 Jan 1995 stillbirths occurring in the Republic of Ireland must be registered; stillbirths which occurred before that date can also be registered but evidence is required.^[14] For the purposes of civil registration, s.1 of the Stillbirths Registration Act 1994 refers to :-

"...a child weighing at least 500 grammes, or having reached a gestational age of at least 24 weeks who shows no signs of life."

United Kingdom [edit]

The registration of still-births has been required in England and Wales from 1927, in Scotland from 1939 but is not required in Northern Ireland [2].

England and Wales

For the purposes of the Births and Deaths Registration Act 1926 (as amended), section 12 contains the definition that :-

“still-born” and “still-birth” shall apply to any child which has issued forth from its mother after the twenty fourth week of pregnancy and which did not at any time after being completely expelled from its mother, breathe or show any other signs of life.

A similar definition is applied within the Births and Deaths Registration Act 1953 (as amended), contained in s.41.

The above definitions apply within those Acts thus other legislation will not necessarily be in identical terms.

s.2 of the 1953 Act requires that registration of a birth takes place within 42 days of the birth except where an inquest takes place or the child has been "found exposed" in which latter case the time limit runs from the time of finding.

Extracts from the register of still-births are restricted to those who have obtained consent from the Registrar General for England and Wales.

Scotland

Section 56(1) of the Registration of Births, Deaths and Marriages (Scotland) Act 1965 (as amended) contains the definition that :-

“still-born child” means a child which has issued forth from its mother after the twenty-fourth week of pregnancy and which did not at any time after being completely expelled from its mother breathe or show any other signs of life, and the expression “still-birth” shall be construed accordingly

s.21(1) of the same Act requires that :-

Except so far as otherwise provided by this section or as may be prescribed, the provisions of this Part of this Act shall, so far as applicable, apply to still-births in like manner as they apply to births of children born alive.

In the general case, s.14 of the Act requires that a birth has to be registered within 21 days of the birth or of the child being found.

Unlike the registers for births, marriages, civil partnerships and deaths, the register of still-births is not open to public access and issue of extracts requires the permission of the Registrar General for Scotland.

Northern Ireland

In Northern Ireland the Births and Deaths Registration (Northern Ireland) Order 1976[3], as amended contains the definition :-

“still-birth” means the complete expulsion or extraction from its mother after the twenty-fourth week of pregnancy of a child which did not at any time after being completely expelled or extracted breathe or show any other evidence of life.

Registration of still-births can be made by a relative or certain other persons involved with the still-birth but it is not compulsory to do so. Registration takes place with the District Registrar for the Registration District where the still-birth occurred or for the District in which the mother is resident. A still-birth certificate will be issued to the registrant with further copies only available to those obtaining official consent for their issue. Registration may be made within three months of the still-birth^[15]

United States [edit]

In the United States, there is no standard definition of the term 'stillbirth'.^[12] The Centers for Disease Control and Prevention collects statistical information on "live births, fetal deaths, and induced termination of pregnancy" from 57 reporting areas in the United States. Each reporting area has different guidelines and definitions for what is being reported; many do not use the term "stillbirth" at all. The federal guidelines suggests (at page 1) that fetal death and stillbirth can be interchangeable terms. The CDC definition of "fetal death" is based on the definition promulgated by the World Health Organization in 1950 (see section above on Canada). Researchers are learning more about the long term psychiatric sequelae of traumatic birth and believe the effects may be intergenerational ^[16]

The federal guidelines recommend reporting those fetal deaths whose birth weight is over 12.5 oz (350g), or those more than 20 weeks gestation. Forty-one areas use a definition very similar to the federal definition, thirteen areas use a shortened definition of fetal death, and three areas have no formal definition of fetal death. Only 11 areas specifically use the term 'stillbirth', often synonymously with late fetal death, however they are split between whether stillbirths are "irrespective of the duration of pregnancy", or whether some age or weight constraint is applied. A movement in the U.S. has changed the way that stillbirths are documented through vital records. Previously, only the deaths were reported. However 27 states have enacted legislation that offers some variation of a birth certificate as an option for parents who choose to pay for one.

References [edit]

^ Nguyen RH, Wilcox AJ (December 2005). "Terms in reproductive and perinatal epidemiology: 2. Perinatal terms". J Epidemiol Community Health 59 (12): 1019–21. doi:10.1136/jech.2004.023465. PMC 1732966. PMID 16286486. "There is probably no health outcome with a greater number of conflicting, authoritative, legally mandated definitions. The basic WHO definition of fetal death is the intrauterine death of any conceptus at any time during pregnancy. However, for practical purposes, legal definitions usually require recorded fetal deaths to attain some gestational age (16, 20, 22, 24, or 28 weeks) or birth weight (350, 400, 500, or 1000 g). In the US states, there are eight different definitions by combinations of gestational age and weight, and at least as many in Europe."
^ Collins JH (February 2002). "Umbilical cord accidents: human studies". Semin. Perinatol. 26 (1): 79–82. doi:10.1053/sper.2002.29860. PMID 11876571.
^ "Female genital mutilation and obstetric outcome: WHO collaborative prospective study in six African countries" Retrieved on 2012-2-22
^ ^a ^b Collins JH (M.D.). "Silent Risk: Issues About the Human Umbilical Cord" Retrieved on 2009-3-17
^ Bythell M, et al. (2008) The contribution of late termination of pregnancy to stillbirth rates in Northern England, 1994-2005. The British Journal of Obstetrics and Gynaecology, 115(5):664-666
^ http://www.preginst.com/pucp.html
^ "Studies identify stillbirth risk factors, causes". CBS News.
^ Gordon, Adrienne (Dr). "Department of Neonatal Medicine Protocol Book: Royal Prince Alfred Hospital". Retrieved 2006-09-13.
^ Cacciatore, J. (2007). A phenomenological exploration of stillbirth and the effects of ritualization on maternal anxiety and depression, University of Nebraska-Lincoln Press, Digital Commons ; Froen, J.F. (2005).
^ Lahra MM, Gordon A, Jeffery HE (2007). "Chorioamnionitis and fetal response in stillbirth". Am. J. Obstet. Gynecol. 196 (3): 229.e1–4. doi:10.1016/j.ajog.2006.10.900. PMID 17346531. "Stillbirth is defined within Australia as fetal death (no signs of life), whether antepartum or intrapartum, at ≥20 weeks of gestation or ≥400 g birthweight, if gestational age is unknown."
^ Statistics Canada ("Canada's National Statistical Agency"), History, Vital Statistics - Stillbirth Database, in Vital Statistics – Stillbirth Database.
^ ^a ^b Centers for Disease Control and Prevention. State Definitions and Reporting Requirements (PDF) (1997 Revision ed.). National Center for Health Statistics.
^ http://www.initiative-regenbogen.de/gesetze.htm
^ http://www.citizensinformation.ie/categories/birth-family-relationships/miscarriage-and-stillbirth/registering_stillbirth
^ NI Direct - Registering a Still-birth [1]
^ Cacciatore, J. (2010). Unique stories of women and their families after the death of a baby. Journal of Healthcare Social Work, 49(2), 134-148.

External links [edit]

Unspoken Grief.com Support for parents grieving due to perinatal loss (miscarriage, stillbirth, neonatal death).A safe place to share your story.
Share Pregnancy & Infant Loss Support Support for parents who have experienced the death of a baby through early pregnancy loss, stillbirth or infant death.
The Wisconsin Stillbirth Service Program (WiSSP), a branch of the University of Wisconsin-Madison's Clinical Genetics Center. One of the foremost authorities on the causes of stillbirth and responsible for many stillbirth evaluation protocols, including the widespread use of the Kleihauer-Betke test in deciding whether Rh disease is to blame for a stillbirth. This program is now directed by Dr. Elispeth McPherson at the Marshfield Clinic in Marshfield, WI.
Pregnancy Institute founded by Dr. Jason H. Collins, OB/GYN specializes in umbilical cord research
Investigating perinatal death: a review of the options when autopsy consent is refused.
UK Stillbirth and Neonatal Death Society

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 死産の発生率、病因、および予防 incidence etiology and prevention of stillbirth
2. 死産の診断およびマネージメント diagnosis and management of stillbirth
3. 死産の評価 evaluation of stillbirth
4. 死産後の親に対するカウンセリング counseling parents after stillbirth
5. 産科におけるアレイ比較ゲノムハイブリダイゼーション（aCGH）の利用 use of array comparative genomic hybridization acgh in obstetrics

English Journal

Impact of oral administration of compost extract on gene expression in the rat gastrointestinal tract.

Satoh T, Nishiuchi T, Naito T, Matsushita T, Kodama H, Miyamoto H, Miyamoto H.SourceDivision of Molecular Hematology, Kitasato University Graduate School of Medical Sciences, 1-15-1 Kitasato, Minami-ku, Sagamihara 252-0373, Japan.
Journal of bioscience and bioengineering.J Biosci Bioeng.2012 Nov;114(5):500-5. doi: 10.1016/j.jbiosc.2012.05.026. Epub 2012 Jun 29.
Oral administration of an extract consisting of compost fermented with thermophiles to pigs reduces the incidence of stillbirth and promotes piglet growth. However, the mechanism by which the compost extract modulates the physiological conditions of the animals remains largely unknown. Here, we inve
PMID 22748358

Sows exposed to octylphenol in early gestation: No estrogenic effects in male piglets, but increased rate of stillbirth.

Gralén B, Visalvethaya W, Ljungvall K, Tantasuparuk W, Norrgren L, Magnusson U.SourceDivision of Reproduction, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Theriogenology.Theriogenology.2012 Oct 15;78(7):1494-9. doi: 10.1016/j.theriogenology.2012.06.028. Epub 2012 Aug 24.
Octylphenol is an industrial chemical with estrogenic effects both in vitro and in vivo. In this study the effects of short-term intramuscular exposure to 0.1 mg/kg of body weight and 1.0 mg/kg of body weight in early gestation were evaluated in pregnant sows with respect to reproductive parameters
PMID 22925640