Stillbirth
| Stillbirth | |
|---|---|
| Classification and external resources | |
Ultrasonography is often used to diagnose stillbirth. |
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| ICD-10 | P95 |
| MedlinePlus | 002304 |
| eMedicine | topic list |
| MeSH | D050497 |
A stillbirth occurs when a fetus has died in the uterus. A wide variety of definitions exist.[1] The Australian definition specifies that fetal death is termed a stillbirth after 20 weeks gestation or the fetus weighs more than 400 grams (14 oz). 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.
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[edit] Human stillbirth
[edit] Causes
The causes of a large percentage of human stillbirths remain 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
- umbilical cord accidents[3]
- "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.
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- 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".[4]
[edit] Prenatal diagnosis
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.[3] 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 little space in the uterus 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.
[edit] Constricted umbilical cord
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.[5]
[edit] Prevention
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.
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.[6]
[edit] Prenatal maternal treatment
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.
[edit] Prevalence
Stillbirth is a relatively common, but often random, occurrence. 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,[7] 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.[8]
In developing countries, where medical care can be of low quality or unavailable, the stillbirth rate is much higher.
[edit] Legal definitions of stillbirth
[edit] Australia
In Australia any stillborn weighing more than 400 grams, or more than 20 weeks in gestation, must have its birth registered.[9]
[edit] Austria
In Austria a stillbirth is defined as birth of a child of at least 500g weight without vital signs, i.e. blood circulation, breath or muscle movements.
[edit] Canada
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." [10] 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.[11]
[edit] Germany
In Germany a stillbirth is defined as birth of a child of at least 500g weight without blood circulation or breath. Details for burial are varying in the federal states.[12]
[edit] Ireland
In Ireland, stillbirths must be registered as such. A stillbirth is legally defined as a child weighing at least 500 grammes, or having reached a gestational age of at least 24 weeks.[13]
[edit] United Kingdom
Throughout the United Kingdom, stillbirths must be registered by law. The Stillbirth Definition Act (1992) states: "any ‘child’ expelled or issued forth from its mother after the 24th week of pregnancy that did not breathe or show any other signs of life should be registered as a stillbirth."[14] In England and Wales, this must be done within 42 days and a Stillbirth Certificate is issued to the parent(s).[15] In Scotland, this must be done within 21 days.[16]
[edit] United States
In the United States, there is no standard definition of the term 'stillbirth'.[11] 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 [17]
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 MAB Legislative Page [MAB legislative page]
[edit] See also
- Childbirth
- Coffin birth
- Live birth
- Perinatal death
- Abortion
- Maternal death
- Stillbirth and Neonatal Death Society
[edit] References
- ^ 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. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1732966. "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.
- ^ 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
- ^ http://www.cbsnews.com/8301-500368_162-57342588/studies-identify-stillbirth-risk-factors-causes/
- ^ Gordon, Adrienne (Dr). "Department of Neonatal Medicine Protocol Book: Royal Prince Alfred Hospital". http://www.sswahs.nsw.gov.au/RPA/neonatal/html/Newprot/stillbirths.html. 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 (PDF). State Definitions and Reporting Requirements (1997 Revision ed.). National Center for Health Statistics. http://www.cdc.gov/nchs/data/misc/itop97.pdf.
- ^ http://www.initiative-regenbogen.de/gesetze.htm
- ^ http://www.citizensinformation.ie/categories/birth-family-relationships/miscarriage-and-stillbirth/registering_stillbirth
- ^ "Registration of Stillbirths and Certification for Pregnancy Loss before 24 Weeks Gestation" Royal College of Midwives. Retrieved September 27, 2007
- ^ Guide to registering stillbirths in the UK
- ^ Registering a stillbirth General Register Office for Scotland
- ^ 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.
[edit] Further reading
G. J. Barker-Benfield, "Stillbirth and Sensibility The Case of Abigail and John Adams," Early American Studies, An Interdisciplinary Journal, Spring 2012, Vol. 10 Issue 1, pp 2–29.
[edit] External links
- 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
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