Talk:2009 Lecture 23

Introduction

There are a great number of comprehensive, scientific and general, books and articles that cover Parturition, Birth or Childbirth.

Birth or parturition is a critical stage in development, representing in mammals a transition from direct maternal support of fetal development, physical expulsion and establishment of the newborns own respiratory, circulatory and digestive systems.

File:1770birth sm.jpg	File:JAMA CesareanDelivery.gif	File:Birth.jpg
Birth - Stage 1	[birth6.htm Caesarean]	Newborn infant

These notes only cover the biological processes involved in birth [birth4.htm fetal signaling changes] and [birth5.htm maternal signaling changes]. Note that there is a growing worldwide trend in developed countries toward [birth6.htm caesarean section] delivery.

Other Pages: [../Notes/respire6.htm Respiratory Development - Birth] |

Some Recent Findings

Markovic D, Vatish M, Gu M, Slater D, Newton R, Lehnert H, Grammatopoulos DK. The onset of labour alters corticotropin-releasing hormone type 1 receptor (CRH-R1) variant expression in human myometrium: putative role of IL-1{beta} Endocrinology. 2007 Apr 12

Zakar T, Hertelendy F. Progesterone withdrawal: key to parturition. Am J Obstet Gynecol. 2007 Apr;196(4):289-96.

"In most subprimate placental mammals, the withdrawal of progesterone before the initiation of labor is manifest by a significant drop in circulating progesterone levels, which is due to either luteolysis or changes in placental steroidogenesis, which shunts precursors towards estrogen production. No such events can be demonstrated in human pregnancy."

Birth Models

File:1770birth sm.jpg	File:1770birth2 sm.jpg
Cephalic presentation of engagement	Disengagement of the head in vertex presentation

(More? [../history/page1770.htm Development History - 1770 - Obstetric Models])

Reading

Human Embryology (2nd ed.) Larson Chapter 15 p471-488
The Developing Human: Clinically Oriented Embryology (6th ed.) Moore and Persaud Chapter 7 p129-167
Before we Are Born (5th ed.) Moore and Persaud Ch
Essentials of Human Embryology Larson Ch
Human Embryology Fitzgerald and Fitzgerald
General Reading- Pregnancy and Childbirth S Kitzinger Doubleday, Sydney ISBN 0 86824 048 6

Gestation Period

The median duration of gestation for first births from assumed ovulation to delivery was 274 days (just over 39 weeks). For multiple births, the median duration of pregnancy was 269 days (38.4 weeks).

"...one should count back 3 months from the first day of the last menses, then add 15 days for primiparas or 10 days for multiparas, instead of using the common algorithm for Naegele's rule." Reference: Mittendorf R, Williams MA, Berkey CS, Cotter PF. The length of uncomplicated human gestation. Obstet Gynecol. 1990 Jun;75(6):929-32

Historically, Franz Carl Naegele (1777-1851) developed the first scientific rule for estimating length of a pregnany.

This topic has been separated into pages related to the whole signaling [birth3.htm process overview].

Preterm Birth

There is a specific page online [birthpremature.htm Premature Birth] being currently prepared.

A study has shown that risks of preterm birth in low abnormal birth weight (intrauterine growth restriction) and high (large for gestational age) categories are 2- to 3-fold greater than the risk among appropriate-for-gestational-age infants.

In another study of placenta previa, low birth weight is due mainly to preterm delivery and to a lesser extent with fetal growth restriction.

(More? HSTAT - Management of Preterm Labor)

Reference: Lackman F, Capewell V, Richardson B, daSilva O, Gagnon R. The risks of spontaneous preterm delivery and perinatal mortality in relation to size at birth according to fetal versus neonatal growth standards. Am J Obstet Gynecol. 2001 Apr;184(5):946-53.

Ananth CV, Demissie K, Smulian JC, Vintzileos AM. Relationship among placenta previa, fetal growth restriction, and preterm delivery: a population-based study. Obstet Gynecol. 2001 Aug;98(2):299-306.

(More? [birthpremature.htm Premature Birth])

Computer Activities

Birth Date Calculator

HTML: <noscript>NOTE: You need Javascript to use the calculator, which your browser has apparently disabled.HTML: </noscript>

When did your last period begin? Your approximate birth (due) date is:

== References ==

Links require internet connection.

NCBI Bookshelf

Health Services/Technology Assessment Text (HSTAT) Bethesda (MD): National Library of Medicine (US), 2003 Oct.

Management of Preterm Labor

Management of Prolonged Pregnancy

Cesarean Childbirth

Vaginal Birth After Cesarean (VBAC) Volume 1 and Volume 2

Reviews

Bernal AL. Overview of current research in parturition. Exp Physiol. 2001 Mar;86(2):213-22. Review.
Young IR. The comparative physiology of parturition in mammals. Front Horm Res. 2001;27:10-30.
Schwartz J, McMillen IC. Fetal hypothalamus-pituitary-adrenal axis on the road to parturition. Clin Exp Pharmacol Physiol. 2001 Jan-Feb;28(1-2):108-12. Review.
Challis JRG, Matthews SG, Gibb W, Lye Endocrine and paracrine regulation of birth at term and preterm. Endocr Rev. 2000 Oct;21(5):514-50. Review.
Muglia LJ. Genetic analysis of fetal development and parturition control in the mouse. Pediatr Res. 2000 Apr;47(4 Pt 1):437-43. Review.
Drover JW, Casper RF. Initiation of parturition in humans. Can Med Assoc J. 1983 Feb 15;128(4):387-92.

Articles

Ochedalski T, Lachowicz A. Maternal and fetal hypothalamo-pituitary-adrenal axis: different response depends upon the mode of parturition. Neuro Endocrinol Lett. 2004 Aug;25(4):278-82.

Search PubMed Now: childbirth | parturition

Internal LinksBirth

File:VirginiaApgarsm.jpg In the early 1950's Virginia Apgar published the research article that was the basis of a simple diagnostic test, the 10-point Apgar score, for neonatal well-being at birth that continues to be used today.

There are a number of different neonatal screening (newborn screening) programs in different countries testing for various "common" abnormalities and infections. In addition to the Gutherie test there are also physical tests for hip displasia and a growing number of countries testing of newborn hearing.

File:Gutheriecard.jpg	File:Newbornecg.jpg	File:CDH.jpg	File:Newbornhear.jpg
Guthrie Card	Heart	Hip Displasia	Hearing

Related Pages: [apgar.htm Birth - Apgar] | [../Defect/page7.htm Prenatal Diagnosis]

Some Recent Findings

Screening for MCAD deficiency in newborns. Loughrey C, Bennett MJ. BMJ. 2009 Mar 12;338:b971. doi: 10.1136/bmj.b971. PMID: 1928244

"This month (March 2009) sees the expansion of newborn screening in England and Northern Ireland to include screening for medium chain acylcoenzyme A dehydrogenase (MCAD) deficiency within the entire newborn population. MCAD deficiency is the most common inherited disorder of mitochondrial fatty acid oxidation in people from northern Europe. This autosomal recessive metabolic disease affects about one in 10 000 people in the United Kingdom,1 and it has a common mutation (985A>G) with a carrier rate of around one in 65.2."

(More? [#MCAD Medium-Chain Acyl-CoA Dehydrogenase Deficiency])

Study Supports Screening Babies for Heart-Rhythm Defect "Routine electrocardiogram (ECG) screening for newborns would save many lives by identifying a potentially deadly genetic condition called long QT syndrome, Italian researchers report."

Kempers MJ, Lanting CI, van Heijst AF, van Trotsenburg AS, Wiedijk BM, de Vijlder JJ, Vulsma T. Neonatal screening for congenital hypothyroidism based on T4, TSH and TBG measurement: Potentials and pitfalls. J Clin Endocrinol Metab. 2006 Jun 20; "The Dutch incidence figures for CH belong to the highest worldwide suggesting that the T4-TSH-TBG screening program is an efficient method to detect CH of variable etiology and severity. Still, a small percentage of children with CH escaped detection via this screening approach. Severe illness and TBG deficiency appear to be responsible for the majority of false-positive referrals."

U.S. Preventive Service Task Force. Screening for developmental dysplasia of the hip: recommendation statement. Am Fam Physician. 2006 Jun 1;73(11):1992-6.

Guthrie Test

Dr Robert Guthrie

A blood screening test developed by Dr Robert Guthrie (1916-95) at University of Buffalo. Test is carried out on neonate (newborn) blood for a variety of known genetic disorders.

Blood is collected using a heelprick and spotted onto a test sheet to dry for later testing. Different countries and medical services have different policies on not only what will be tested for but also how long the test card will be kept following analysis. Check your local service for specific information.

Links: National Coalition PKU Disorders Tribute to Dr Robert Guthrie | Museum of DisABILITIES The Birth of Newborn Screening |

Routine Screened Disorders

Biotinidase Deficiency (OMIM)

Congenital Adrenal Hyperplasia (CAH) (OMIM)

Congenital Hypothyroidism (CH)

Congenital Toxoplasmosis

Cystic Fibrosis (CF) (OMIM)

Galactosemia (GAL) (OMIM)

Homocystinuria (OMIM)

Maple Syrup Urine Disease (MSUD) ([#MCAD MCAD] | OMIM)

Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCAD) (OMIM)

Links: History/Overview of Newborn Screening

Medium-Chain Acyl-CoA Dehydrogenase Deficiency (MCAD)

MCAD deficiency is the most common inherited disorder of mitochondrial fatty acid oxidation in people from northern Europe. It is characterized by an intolerance to prolonged fasting and an inability to generate energy during periods of increased energy demand. The disorder can be severe to fatal in infants.

The other disease characteristics include: recurrent episodes of hypoglycemic coma with medium-chain dicarboxylic aciduria, impaired ketogenesis, and low plasma and tissue carnitine levels.

Gutherie test detected autosomal recessive metabolic disease affects about one in 10 000 people (UK). This mitochondrial protein is encoded by a nuclear gene on chromosome 1 (Gene map locus 1p31) and has a common mutation (985A>G) with a carrier rate of around one in 65.2.

Links: OMIM - MCAD | Cell Biology - Mitochondria

Gene Tests

A new site developed by NIH "GeneTests" provides medical genetics information resources available at no cost to all interested persons. It contains educational information, a directory of genetic testing laboratories and links to other databases such as OMIM.

Links: GeneTests |

Hip Displasia

Non-specific hip instability is a common finding in newborns, particularly in females. More than 80% of clinically unstable hips at birth resolve spontaneously. Screening newborns for Developmental dysplasia of the hip (DDH) shows an incidence in infants between 1.5 and 20 per 1000 births. This incidence is influenced by several factors (diagnostic criteria, gender, genetic and racial factors, and age of the population).

(Text modified from: Screening for developmental dysplasia of the hip)

Links: [../Notes/skmus2.htm#HIPDISLOCATION Musculoskeletal Abnormalities- Congenital Dislocation of the Hip] | [hipdyssyn.pdf Screening for Developmental Dysplasia of the Hip PDF] | Screening for developmental dysplasia of the hip. Evidence synthesis no. 42. Rockville, Md.: Agency for Healthcare Research and Quality http://www.ahrq.gov/downloads/pub/prevent/pdfser/hipdyssyn.pdf | U.S. Preventive Service Task Force. Screening for developmental dysplasia of the hip: recommendation statement. Am Fam Physician. 2006 Jun 1;73(11):1992-6.

Hearing

The incidence of significant permanent hearing loss is approximately 1-3/1000 newborns. Neonatal hearing screening is carried out in the USA, UK and in Australia (2002 NSW Statewide Infant Screening Hearing Program, [#SWISH SWISH]) There is a general guide giving a timetable for a number of simple responses that a neonate should make if hearing has developed normally (More? [#Hearing_Check_List Neonatal Hearing Check List]).

State Wide Infant Screening Hearing Program (SWISH) a newborn hearing testing program using an automated auditory response technology (AABR). Program was introduced in NSW Australia in 2002 across 17 area health service coordinators. It is thought that in NSW 86,000 births/year = 86-172 babies potentially born with significant permanent hearing loss.

Automated Auditory Brainstem Response (AABR) uses a stimulus which is delivered through earphones and detected by scalp electrodes. The test takes between 8 to 20 minutes and has a sensitivity 96-99%.

References: Kennedy CR. Neonatal screening for hearing impairment. Arch Dis Child. 2000 Nov;83(5):377-83. | Puig T, Municio A, Meda C. Universal neonatal hearing screening versus selective screening as part of the management of childhood deafness. Cochrane Database Syst Rev. 2005 Apr 18;(2):CD003731.

Links: [../Notes/ear.htm Development of the Organs of Audition and Equilibrium] | Australia NSW Statewide Infant Screening - Hearing Program What is SWISH? | eMJA Newborn hearing screening: decision time for Australia | NSW Health Pamphlet Why does my baby need a hearing check? | eMJA Does every baby get a newborn screening test? | United Kingdom Newborn Hearing Screening Programme | USA National Center for Hearing Assessment and Management | Health Services/Technology Assessment Text Early Identification of Hearing Impairment in Infants and Young Children

Neonatal Hearing Check List

The timing and types of responses listed below reflect only a rough guide for the general population. Abnormalities in neurological, visual or motor skill development can also affect responses.

Birth to 3 months

Reacts to loud sounds
Quiets to familiar voices or sounds
Makes cooing noises
Responds to speech by looking at speaker‚Äôs face

3 to 6 months

Turns eyes or head toward sounds
Starts to make speech-like sounds
Laughs and makes noises to indicate pleasure and displeasure

6 to 9 months

Babbles, ‚Äòdada‚Äô‚Äòma-ma‚Äô‚Äòbaba‚Äô
Shouts/vocalises to get attention
Will often respond to ‚Äòno‚Äô and own name
Responds to singing and music

9 to 12 months

Imitates speech sounds of others
Understands simple words, eg ‚Äòball‚Äô,‚Äòdog‚Äô, ‚Äòdaddy‚Äô
Turns head to soft sounds
First words emerge

12 to 18 months

Appears to understand some new words each week
Follows simple spoken instructions, eg ‚Äòget the ball‚Äô
Points to people, body parts or toys when asked
Continually learns new words to say although may be unclear

18 to 24 months

Listens to simple stories or songs
Combines two or more words in short phrases eg ‚Äòmore juice‚Äô

(Hearing Check List text based upon NSW Health Pamphlet 2002 - Why does my baby need a hearing check?)

Heart

An electrocardiogram (ECG / EKG) is an electrical recording of the heart which may identify electrical disorders including long QT syndrome.

Schwartz PJ, Garson A Jr, Paul T, Stramba-Badiale M, Vetter VL, Wren C; European Society of Cardiology. Guidelines for the interpretation of the neonatal electrocardiogram. A task force of the European Society of Cardiology. Eur Heart J. 2002 Sep;23(17):1329-44.

Links: [../Notes/heart.htm Cardiovascular System Development] | [../Notes/heart8.htm Embryonic Heart Rate] | Interpretation of electrocardiograms in infants and children. Images Paediatr Cardiol 1999;1:3-13 | Guidelines for the interpretation of the neonatal electrocardiogram | brief history of electrocardiography |

Australian Information

Links: The NSW Newborn Screening Programme | Test to Protect your Baby (PDF) |

American Information

Links: National Newborn Screening and Genetics Resource Center |

History/Overview of Newborn Screening | Medline - Newborn Screening | Medline - Prenatal Testing |

American Academy of Family Physicians The Newborn Examination: Part I. Emergencies and Common Abnormalities Involving the Skin, Head, Neck, Chest, and Respiratory and Cardiovascular Systems | Part II. Emergencies and Common Abnormalities Involving the Abdomen, Pelvis, Extremities, Genitalia, and Spine | Common Issues in the Care of Sick Neonates

American Medical Association "Kids Health" (these are easy to read general public pages American not Australian Information ) | Baby Development by Age | Baby Development by Topic | Childhood Infections | Childhood Immunizations

NCBI Bookshelf

The NCBI Bookshelf contains a number of complete online publications that relate to neonatal development. Of particular interest, is the new resource "Disease Control Priorities in Developing Countries", which talks to important neonatal health issues in these countries.

[#hstat ealth Services/Technology Assessment Text] | [#dcp2 Disease Control Priorities in Developing Countries] | [#bnchm Basic Neurochemistry] |

Health Services/Technology Assessment Text (HSTAT) Bethesda (MD): National Library of Medicine (US), 2003 Oct.

Criteria for Determining Disability in Infants and Children: Low Birth Weight

Effects of Omega-3 Fatty Acids on Child and Maternal Health

Management of Neonatal Hyperbilirubinemia

Criteria for Determining Disability in Infants and Children: Failure to Thrive

Newborn Screening for Sickle Cell Disease and Other Hemoglobinopathies

Early Identification of Hearing Impairment in Infants and Young Children

The Effect of Corticosteroids for Fetal Maturation on Perinatal Outcomes

Improving Treatment for Drug-Exposed Infants

Disease Control Priorities in Developing Countries (2nd ed.) Dean T. Jamison, Joel G. Breman, Anthony R. Measham, George Alleyne, Mariam Claeson, David B. Evans, Prabhat Jha, Anne Mills, Philip Musgrove, editors Washington (DC): IBRD/The World Bank and Oxford University Press; 2006

Newborn Survival

Maternal and Perinatal Conditions

Basic Neurochemistry, Molecular, Cellular, and Medical Aspects (6th ed.) Siegal, George J.; Agranoff, Bernard W.; Albers, R. Wayne; Fisher, Stephen K.; Uhler, Michael D., editors. Philadelphia: Lippincott, Williams & Wilkins; c1999.

etiology of schizophrenia may involve pathological processes during brain development

steroid hormone receptors become evident in target neurons of the brain

Biochemistry of Thyroid Hormone Actions on Brain

"Hypothyroidism increases synaptic density, at least transiently. Interesting parallels with synapse formation are reported for learning behavior in rats; neonatal hypothyroidism impairs learning ability, whereas hyperthyroidism accelerates learning initially, followed by a decline later in life"

Type II glutaric aciduria

"The outlook is almost uniformly fatal, and the few babies who survive have severely compromised development and a cardiomyopathy that usually proves fatal. In rare cases, a patient stays asymptomatic until after the neonatal period, when hepatomegaly, vomiting, metabolic acidosis, hypoglycemia and a proximal myopathy become evident."

brain utilizes ketones in states of ketosis

"Significant utilization of ketone bodies by the brain is, however, normal in the neonatal period. The newborn infant tends to be hypoglycemic but becomes ketotic when it begins to nurse because of the high fat content of the mother's milk. When weaned onto the normal, relatively high-carbohydrate diet, the ketosis and cerebral ketone utilization disappear."

WWW Links

International Society for Neonatal Screening International Society for Neonatal Screening | Fact Sheets |

World Health Organization (WHO) Immunization, Vaccines and Biologicals

Kidshealth Org Newborn Screening Tests

New England Consortium of Metabolic Programs (USA) - The Story of Newborn Screening by Harvey Levy

Normal Health Statistics

[../Stats/page2.htm Australian Birth Statistics | ][../Stats/page1.htm International and Australian Population Statistics | ][../Stats/page3.htm WHO Normal Population Statistics | ]Fact Sheets | [../Stats/page3a.htm#perinatal Global Perinatal and Maternal Causes of Death | ][../Stats/page4a.htm Population Comparisons between Countries | ][../Stats/page4a.htm#Population%20Data Developed and developing | ][../Stats/page4a.htm#au1 Australian neighbours | ][../Stats/page4a.htm#au2 Australian Trading Partners | ]USA National Center for Health Statistics - Child

Normal population statistics derived from a number of different sources (as shown on individual pages).

References

PubMed

Reviews

Kempers MJ, Lanting CI, van Heijst AF, van Trotsenburg AS, Wiedijk BM, de Vijlder JJ, Vulsma T. Neonatal screening for congenital hypothyroidism based on T4, TSH and TBG measurement: Potentials and pitfalls. J Clin Endocrinol Metab. 2006 Jun 20;

U.S. Preventive Service Task Force. Screening for developmental dysplasia of the hip: recommendation statement. Am Fam Physician. 2006 Jun 1;73(11):1992-6.

Schwartz PJ, Garson A Jr, Paul T, Stramba-Badiale M, Vetter VL, Wren C; European Society of Cardiology. Guidelines for the interpretation of the neonatal electrocardiogram. A task force of the European Society of Cardiology. Eur Heart J. 2002 Sep;23(17):1329-44.

Articles

Kennedy CR. Neonatal screening for hearing impairment. Arch Dis Child. 2000 Nov;83(5):377-83.

Puig T, Municio A, Meda C. Universal neonatal hearing screening versus selective screening as part of the management of childhood deafness. Cochrane Database Syst Rev. 2005 Apr 18;(2):CD003731.

Search PubMed

Search July 2006 "neonatal screening" 4,409 reference articles of which 682 were reviews.

Search PubMed: term = neonatal screening | newborn screening | Guthrie Test |