Premature birth

Premature birth

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*anxietycite journal |author=Dole N, Savitz DA, Hertz-Picciotto I, Siega-Riz AM, McMahon MJ, Buekens P |title=Maternal stress and preterm birth |journal=Am. J. Epidemiol. |volume=157 |issue=1 |pages=14–24 |year=2003 |pmid=12505886 |doi=10.1093/aje/kwf176|url=http://171.66.121.65/cgi/reprint/157/1/14]

*periodontal disease (OR = 4.45) [Jeffcoat, Marjorie K., Nico C. Geurs, Michael S. Reddy, Suzanne P. Cliver, Robert L. Goldenberg, and John C. Hauth. "Periodontal Infection and Preterm Birth." The Journal of the American Dental Association 132 (2001): 875–880. 25 April 2007 [http://jada.ada.org/cgi/content/abstract/132/7/875] .]

Whether or not urinary tract infections directly cause preterm birth is uncertain, however, it is known that urinary tract infections increase pre-eclampsia, which as stated above, increases the risk of preterm birth. Sexually transmitted disease (STD), Beta Strep, kidney disease, and uterine infections are also suspected of increasing the risk of preterm birth.

Adequate maternal nutrition is important to fetal development and a diet low in saturated fat and cholesterol may help reduce the risk of a preterm delivery. ["Cholesterol Lowering Diet for Pregnant Women May Help Prevent Preterm Birth." BMJ: British Medical Journal 331 (2005): 1093. 1 May 2007 [http://web.ebscohost.com/ehost/detail?vid=4&hid=117&sid=fe387f34-508b-46a8-8f32-ff975c1297a4%40sessionmgr9] .]

Factors related to pregnancy history that have been shown to increase the risk of preterm birth include:
*prior preterm delivery (OR = 2.79)
*prior induced abortion (OR = 1.6)
*antepartum hemorrhage / vaginal bleeding during labor
*prior miscarriage

Multiple pregnancies (twins, triplets, etc.) are another significant factor in preterm birth. The March of Dimes Multicenter Prematurity and Prevention Study found that 54% of twins were delivered preterm vs. 9.6% of singleton births.cite journal |author=Gardner MO, Goldenberg RL, Cliver SP, Tucker JM, Nelson KG, Copper RL |title=The origin and outcome of preterm twin pregnancies |journal=Obstet Gynecol |volume=85 |issue=4 |pages=553–7 |year=1995 |pmid=7898832 |doi=10.1016/0029-7844(94)00455-M |url=http://www.greenjournal.org/cgi/pmidlookup?view=long&pmid=7898832]

Women who have tried to conceive for more than a year before getting pregnant are at a higher risk for premature birth. A recent study done by Dr. Olga Basso of the University of Aarhus in Denmark and Dr. Donna Baird of the U.S. National Institute of Environmental Health Sciences suggests that women who had difficulty conceiving were about 40 percent higher risk of preterm birth than those who had conceived easily.

Finally, the use of tobacco and alcohol during pregnancy also increases the chance of preterm delivery. Tobacco is the most commonly abused drug during pregnancy and also contributes significantly to low birth weight delivery. [Shiono, Patricia H., Mark A. Klebanoff, Robert P. Nugent, Mary F. Cotch, Diana G. Wilkins, Douglas E. Rollins, Christopher J. Carey, and Richard E. Behrman. "Fetus-Placenta-Newborn: the Impact of Cocaine and Marijuana Use on Low Birth Weight and Preterm Birth: a Multicenter Study." American Journal of Obsetrics and Gynecology 172 (1995): 19–27. 1 May 2007 [http://pt.wkhealth.com/pt/re/ajog/abstract.00000447-199501000-00003.htm;jsessionid=GGQfDBDtJTWynh5ZX5cT2f1bw72GDVwyBbjh7q1rvNqj8b2L3mkQ!-1870145763!-949856144!8091!-1] .] [Parazzini, F, L. Chatenoud, M. Surace, L. Tozzi, B. Salerio, G. Bettoni, and G. Benzi. "Moderate Alcohol Drinking and Risk of Preterm Birth." European Journal of Clinical Nutrition 57 (2003): 1345. 1 May 2007 [http://web.ebscohost.com/ehost/detail?vid=3&hid=3&sid=afc585c7-2d1e-43e5-87b5-f9c746caf1fc%40sessionmgr8] .]

Prevention of preterm birth

Recent research has identified possible methods to "prevent" preterm birth, pre-eclampsia/eclampsia, premature rupture of membranes, and preterm labor.

These include self-care methods to reduce infections, nutritional and psychological interventions, and the control of preterm birth risk factors (e.g. working long hours while standing on feet, carbon monoxide exposure, domestic abuse, and other factors). Injection with a form of progesterone (17 alpha-hydroxyprogesterone caproate) although the safety of this treatment for the fetus has been questioned by the FDA and its expert panel due to an associated increase in miscarriage and fetal death [ [http://www.fda.gov/ohrms/dockets/ac/cder06.html#rhdac Advisory Committees: CDER 2006 Meeting Documents ] ] , the use of vaginal progesterone ,taking fish oil supplements Fact|date=August 2008, and self-monitoring vaginal PH followed by yogurt treatment or Clindamycin treatment if the PH was too high all seem to be effective at reducing the risk of preterm birth. [ Lamont RF and Jaggat AN. Emerging drug therapies for preventing spontaneous preterm labor and preterm birth. Expert Opin Investig Drugs. 2007 16:337–45. PMID 17302528] [ Hoyme UB and Saling E. Efficient prematurity prevention is possible by pH-self measurement and immediate therapy of threatening ascending infection. Eur J Obstet Gynecol Reprod Biol. 2004 115:148–53. PMID 15262346] This research is quite new; however, doctors using these newer strategies have obtained preterm birth rates as low as 1 to 2%, compared to the 11 to 16% currently in the US. Fact|date=February 2007

Although short term use of folic acid may not have an effect, genetic variation in folate metabolism affects prematurity, and a recent report suggests that usage by mothers for more than a year before birth can reduce premature birth by 50 to 70 percent.cite web|url=http://timesreporter.com/index.php?ID=78878&r=0|title=Study: Giving moms magnesium sulfate cuts risk of cerebral palsy in extreme premature babies ] [PMID 17074544]

Symptoms and indications

The symptoms of an imminent premature birth include:
*Four or more uterine contractions in one hour, before 37 weeks' gestation.
*A watery discharge from the vagina, which may indicate premature rupture of the membranes surrounding the baby.
*Pressure in the pelvis or the sensation that the baby has "dropped".
*Menstrual cramps or abdominal pain.
*Pain or rhythmic tightening in lower abdomen or back.
*Vaginal spotting or bleeding.

Maternal treatments

There are two tactics that can be used to deal with a potential premature birth: delay the arrival of birth as much as possible, or prepare the prospectively premature fetus for arrival. Both of these tactics may be used simultaneously.

Delaying the premature birth from occurring is typically the most favored option. This gives the fetus or fetuses as much time as possible to mature in the womb. There are a number of techniques that can be used to try to accomplish this. The first resort is usually complete bed rest. Maintaining a horizontal position reduces pressure on the cervix, which may allow it to stay lengthened longer, and avoiding unnecessary movement may reduce uterine irritation, which can lead to contractions. Likewise, proper nutrition and especially hydration are important: dehydration can lead to premature uterine contractions. In a hospital setting, a drug-free IV drip may be used to try to stop premature labor simply by improving the mother's hydration. Lastly, there are anti-contraction medications (tocolytics), such as ritodrine, fenoterol, nifedipine and atosiban, although these do not appear to have more than a short-term effect on delaying delivery.

Premature birth cannot always be prevented. Severely premature infants may have underdeveloped lungs, because they are not yet producing their own surfactant. This can lead directly to Respiratory Distress Syndrome, also called hyaline membrane disease, in the neonate. To try to reduce the risk of this outcome, pregnant mothers with threatened premature delivery prior to 34 weeks are often administered at least one course of glucocorticoids, a steroid that crosses the placental barrier and stimulates growth in the lungs of the fetus. Typical glucocorticoids that would be administered in this context are betamethasone or dexamethasone, often when the fetus has reached viability at 23 weeks. In cases where premature birth is imminent, a second "rescue" course of steroids may be administered 12 to 24 hours before the anticipated birth. There is no research consensus on the efficacy and side-effects of a second course of steroids, but the consequences of RDS are so severe that a second course is often viewed as worth the risk.

Research reported at the 2008 conference of the Society for Maternal-Fetal Medicine suggests that administration of magnesium sulfate (Epsom salt) to women just before premature birth can cut the rate of cerebral palsy in half. While the compound is cheap and safe, it may make mothers and infants groggy, and details are pending scientific publication.

Newborn complications

Premature infants show physical signs of their prematurity and may develop other problems as well. These include, but are not limited to, the following:

Neurologic
*Apnea of prematurity
*Hypoxic-ischemic encephalopathy (HIE)
*Intracranial hemorrhage
*Retinopathy of prematurity (ROP)
*Developmental disability

Cardiovascular
*Patent ductus arteriosus (PDA)

Respiratory
*Respiratory distress syndrome (RDS or IRDS) (previously called Hyaline membrane disease)
*Chronic lung disease (previously called bronchopulmonary dysplasia or BPD)

Gastrointestinal / metabolic
*Hypoglycemia
*Feeding difficulties
*Rickets of prematurity
*Hypocalcemia
*Inguinal hernia
*Necrotizing enterocolitis (NEC)

Hematologic
*Anemia of prematurity
*Thrombocytopenia
*Hyperbilirubinemia (jaundice)

Infectious
*Sepsis
*Urinary tract infection ref|1

The earliest gestational age at which the infant has at least a 50% chance of survival is referred to as the limit of viability. As NICU care has improved over the last 40 years, viability has reduced to approximately 24 weeks,cite journal |author=Kaempf JW, Tomlinson M, Arduza C, "et al" |title=Medical staff guidelines for periviability pregnancy counseling and medical treatment of extremely premature infants |journal=Pediatrics |volume=117 |issue=1 |pages=22–9 |year=2006 |pmid=16396856 |doi=10.1542/peds.2004–2547 |url=http://pediatrics.aappublications.org/cgi/content/full/117/1/22 |doi_brokendate=2008-06-20 — in particular see [http://pediatrics.aappublications.org/cgi/content-nw/full/117/1/22/T1 TABLE 1 Survival and Neurologic Disability Rates Among Extremely Premature Infants] ] cite journal |author=Morgan MA, Goldenberg RL, Schulkin J |title=Obstetrician-gynecologists' practices regarding preterm birth at the limit of viability |journal=J. Matern. Fetal. Neonatal. Med. |volume=21 |issue=2 |pages=115–21 |year=2008 |pmid=18240080 |doi=10.1080/14767050701866971] although rare survivors have been documented as early as 21 weeks. [http://www.ctv.ca/servlet/ArticleNews/story/CTVNews/20070220/baby_premature_070219/20070220?hub=CTVNewsAt11] Though this date is controversial as gestation in this case was measured from the date of conception rather than the date of her mother's last menstrual period gestation appear 2 weeks less than if calculated by the more common method [http://abcnews.go.com/Health/story?id=2890242&page=1] ] . As risk of brain damage and developmental delay is significant at that threshold even if the infant survives, there are ethical controversies over the aggressiveness of the care rendered to such infants. The limit of viability has also become a factor in the abortion debate.

Some of the complications related to prematurity are not apparent until years after the birth. For example, children who were born prematurely (especially if born less than 1,500 grams) have a higher likelihood of having behavioral problems, delays in motor development, and difficulties in school. Specifically these problems can be described as being within the executive domain and have been speculated to arise due to decreased myelinization of the frontal lobes. [Böhm, Katz-Salamon, Smedler, Lagercrantz & Forssberg: "Developmental Risks and Protective Factors for Influencing cognitive outcome at 5,5 years of age in very-low-birthweight children". Developmental Medicine & Child Neurology 2002, 44: 508–516.] Throughout life they are more likely to require services provided by physical therapists, occupational therapists, or speech therapists.

Treatment measures for a premature infant

The required care for premature infants differs greatly depending on the child's gestational age, birth weight, and overall maturity. Measures common among extremely premature infants include:
*Placing the infant in a warmer or isolette. Premature infants are easily susceptible to cold-stress or hypothermia and infection, and preventing these is a key priority.
*Infants under 32 weeks typically do not produce enough surfactant in their lungs to enable them to breathe on their own. In these cases, surfactant will be administered to assist them.
*A breathing tube may be inserted in the infant's trachea, and a ventilator and supplemental oxygen may be used.
*Adequate nutrition, via a feeding tube or, in extremely premature infants, intravenously. If a feeding tube is used, expressed breast milk from the mother or a breastmilk bank can be used, which lowers the risk of infections such as necrotizing enterocolitis.

Records

James Elgin Gill (born on 20 May 1987 in Ottawa, Canada) was the earliest premature baby in the world. He was 128 days premature (21 weeks and 5 days gestation) and weighed 1 lb. 6 oz. (624 g). He survived and is quite healthy.cite web |url=http://www.powells.com/biblio?show=0553587129&page=excerpt? |title=Powell's Books — Guinness World Records 2004 (Guinness Book of Records) by |accessdate=2007-11-28 |format= |work=] cite web |url=http://www.canada.com/topics/bodyandhealth/story.html?id=db8f33ab-33e9-429f-bedc-b6ca80f61bdc |title=Miracle child |accessdate=2007-11-28 |format= |work=]

Amillia Taylor is also often cited as the most-premature baby.cite news | url = http://news.bbc.co.uk/1/hi/world/americas/6384621.stm | title = Most-premature baby allowed home | publisher = BBC News | date = 2007-02-21 | accessdate=2007-05-05 ] She was born on 24 October 2006 in Miami, Florida, at 21 weeks and 6 days gestation.cite web |url=http://210.245.61.173/en/detail.php? |title=trithuc.thanhnienkhcn.org.vn |accessdate=2007-11-28 |format= |work=] Though this report has created some confusion her gestation was measured from the date of conception (through IVF) rather than the date of her mother's last menstrual period making her appear 2 weeks younger than if gestation was calculated by the more common method [http://abcnews.go.com/Health/story?id=2890242&page=1] ] . At birth she was 9 inches (23 cm) long and weighed 10 ounces (283 grams).cite news | url = http://news.bbc.co.uk/1/hi/world/americas/6384621.stm | title = Most-premature baby allowed home | publisher = BBC News | date = 2007-02-21 | accessdate=2007-05-05 ] She suffered digestive and respiratory problems, together with a brain hemorrhage. She was discharged from the Baptist Children's Hospital on 20 February 2007.

The record for the smallest premature baby to survive was held for some time by Madeline Mann, who was born at 26 weeks weighing 9.9 oz (280 g) and 9.5 inches (24 cm) long.cite web |url=http://www.hindu.com/seta/2004/08/26/stories/2004082600411400.htm |title=The Hindu : A little miracle called Madeline |accessdate=2007-11-28 |format= |work=] This record was broken in September 2004 by Rumaisa Rahman, who was born in the same hospitalcite web |url=http://www.cbsnews.com/stories/2005/02/08/health/main672488.shtml |title=World's Smallest Baby Goes Home, Cellphone-Sized Baby Is Discharged From Hospital — CBS News |accessdate=2007-11-28 |format= |work=] at 25 weeks gestation. At birth she was eight inches (20 cm) long and weighed 244 grams (8.6 ounces). Her twin sister was also a small baby, weighing 563 grams (1 pound 4 ounces) at birth. During pregnancy their mother had suffered from pre-eclampsia, which causes dangerously high blood pressure putting the baby into distress and leading to birth by caesarean section. The larger twin left the hospital at the end of December, while the smaller remained there until 10 February, 2005 by which time her weight had increased to 1.18 kg (2 pounds 10 ounces). [CBS News. 8 February 2005. [http://www.cbsnews.com/stories/2005/02/08/health/main672488.shtml World's Smallest Baby Goes Home] ] Generally healthy, the twins had to undergo laser eye surgery to correct visual problems, a common occurrence among premature babies.

Historical figures who were born prematurely include Johannes Kepler (born in 1571 at 7 months gestation), Isaac Newton (born in 1643, small enough to fit into a quart mug, according to his mother), Winston Churchill (born in 1874 at 7 months gestation), and Anna Pavlova (born in 1885 at 7 months gestation). [Raju, T. N. K. (1980). [http://www.neonatology.org/classics/mj1980/ch28.html Some Famous "High Risk" Newborn Babies] . In "Historical Review and Recent Advances in Neonatal and Perinatal Medicine". Retrieved June 23, 2006.]

ee also

*Macrophage-activation syndrome
*WalkAmerica an annual walking-for-charity event that has raised more than $1.7 billion since 1970 to prevent premature birth

References

External links

* [http://www.aboutkidshealth.ca/prematurebabies Premature Babies Resource Centre] Information about the causes of prematurity, the challenges of premature birth, the development of the baby, and the long-term implication of prematurity.
* [http://www.littlesteps.co.za/ Little Steps] — research-based, resource site for parents with premature infants in NICU and information and training courses for healthcare professionals. Based in South Africa
* [http://www.kidshealth.org/parent/growth/growing/preemies.html Primer on Preemies] — from the Nemours Foundation
* [http://www.gurbutt.co.uk/ Supporting Parents of Older Premature Children in the UK] - Advocating early educational intervention: assessment and provision
* [http://www.lifeslittletreasures.org.au/ Lifes Little Treasures — Supporting Parents and families of premature babies in Australia] — Providing support, encouragement and friendship from parents who have been through similar experiences
* [http://www.lmk.org.au/ Loddon Mallee Kids] — Regional Australia’s support and information network for families and carers of premature and seriously ill infants


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