Foundations Practical - Neonatal

Newborn Infant

Newborn

Some essential systems come online, others continue to develop.

The neonatal period is about the transition from an interuterine placenta and maternally supported life to life to relatively independent life in the external environment.

In developing a broad understanding of the neonatal period you need to think about the two different environments and the effects of loss of placental support. Remember that substantial postnatal development still has to occur in many systems. Identify these systems and the associated changes that occur.

Birth

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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).

Birth Weight

The primary causes of VLBW are premature birth (born <37 weeks gestation, and often <30 weeks) and intrauterine growth restriction (IUGR), usually due to problems with placenta, maternal health, or to birth defects. Many VLBW babies with IUGR are preterm and thus are both physically small and physiologically immature.

Birth weight (grams)	less 500	500 – 999	1,000 – 1,499	1,500 – 1,999	2,000 – 2,499	2,500 – 2,999	3,000 – 3,499	3,500 – 3,999	4,000 – 4,499	4,500 – 4,999	5,000 or more
Classification	Extremely Low Birth Weight		Very Low Birth Weight	Low Birth Weight		Normal Birth Weight			High Birth Weight

Newborn Homoeostasis

Guthrie card

The newborn has to establish:

lung function
circulatory changes
thermoregulation
endocrine function
nutrition
gastrointestinal tract function
waste
kidney function

Australian Birth

Australia’s mothers and babies (2012)

Now briefly consider the current Australian trends in birth and the new reproductive technologies available.

Australian births (2011)

Assisted reproductive technology in Australia and New Zealand

Assisted reproductive technology in Australia and New Zealand 2012

Assisted Reproduction Technology (ART) is also sometimes also used to identify In vitro fertilization (IVF) but now includes many new techniques.

See the 2014 report^[1]

70,082 assisted reproductive technology (ART) treatment cycles performed in Australia (64,905 ) and New Zealand (5,177),
3,590 babies born (including 13,312 liveborn babies) following ART treatment in 2012.
an increase of 5.8% for Australia and a decrease of 0.2% for New Zealand on 2011.
13.7 cycles per 1,000 women of reproductive age (15–44 years) in Australia
Women used their own oocytes or embryos (autologous) in 95.2% of treatments, and 34.8% of all cycles used frozen/thawed embryos.
36,171 women who undertook 66,710 autologous fresh and/or thaw cycles in Australia and New Zealand in 2012.
average, 1.8 cycles per woman were undertaken in 2012, with more cycles per woman in Australia (1.9 cycles per woman) than in New Zealand (1.5 cycles per woman).
increase in cycles where preimplantation genetic diagnosis was performed, from 2.0% of cycles in 2011 to 3.7% of cycles in 2012.
Maternal Age
- women aged under 30, the live delivery rate was 26.0% for both autologous fresh and thaw cycles.
- women aged over 44, the live delivery rate was 0.9% and 4.6% for autologous fresh and thaw cycles respectively.

(More? Assisted Reproductive Technology)

Maternal Changes

Puerperium - six weeks following birth, maternal reproductive organs and physiology return to pre-pregnancy state.
Involution - process of tissue catabolism of uterus.
Lochia - uterine (placental) discharge, blood plus mucous, continues for about 4 weeks.
Mammary - glandular development and function.

Development does not finish at Birth

Many systems continue to grow and differentiate after birth, in particular neural, sensory, respiratory, renal, endocrine and genital.


Newborn Brain Changes - Complex and ongoing processes of neurological development continue postnatally. This can be seen at the very basic level by simply measuring the increase in overall brain weight.	Postnatal lung growth - At birth about 15% of adult alveoli number have formed.

↑ Macaldowie A, Wang YA, Chughtai AA & Chambers GM 2014. Assisted reproductive technology in Australia and New Zealand 2012. Sydney: National Perinatal Epidemiology and Statistics Unit, the University of New South Wales. PDF | eBook

Terms

Note - linked terms in the list below are external resources to the current class content.

Birth Terms

amniotomy - birth medical procedure thought to speed labor, where the amniotic sac is artificially ruptured using a tool (amniohook).

birth - (parturition, partus, childbirth, labour, delivery). expulsion of the foetus from the uterus. (More? birth)

birth weight - (birth-weight) the weight of the neonate measured as soon as possible after birth. (More? birth weight)

Bishop score - (Bishop's score) A clinical test prior to birth named after the obstetrician/gynaecologist Edward H. Bishop (1913-1995) who published a 1964 paper "Pelvic Scoring For Elective Induction". (More? PMID 14199536)

breech - fetal buttocks presented first and can also occur in different forms depending on presentation (complete breech, frank breech, footing breech, knee breech). (More? historic image)

decidual activation - increased uterine proteolysis and extracellular matrix degradation.

dilatation - opening of the cervix in preparation for birth (expressed in centimetres).

effacement - shortening or thinning of the cervix, in preparation for birth.

early cord clamping - placental cord clamping carried out in the first 60 seconds after birth.

forceps - mechanical "plier-like" tool used on fetal head to aid birth.

induction of labour - clinical procedure where labour starts artificially by using a membrane sweep, pessary or hormone drip.

instrumental birth - birth process where the use of clinical instruments is required.

labor - the maternal physiological process of birth. (More? birth)

macrosomia - clinical description for a fetus that is too large, condition increases steadily with advancing gestational age and defined by a variety of birthweights. In pregnant women anywhere between 2 - 15% have birth weights of greater than 4000 grams (4 Kg, 8 lb 13 oz). (More? macrosomia)

membrane rupture - breaking of the amniotic membrane and release of amniotic fluid (water breaking).

morbidity - (Latin, morbidus = "sick" or "unhealthy") refers to a diseased state, disability, or poor health due to any cause.

necrotising enterocolitis - clinical condition mainly seen in preterm infants, where portions of the bowel undergo necrosis.

neonatal - the early postnatal period relating to the birth, it includes the period up to 4 weeks after birth.

obstetric fistula - abnormal connection between the vagina and rectum or bladder caused by a prolonged obstructed labor.

perinatal - the early postnatal period relating to the birth, statistically it includes the period up to 7 days after birth.

presentation - how the fetus is situated in the uterus.

presenting part - part of fetus body that is closest to the cervix.

preterm birth - birth of an infant before GA 37 weeks of pregnancy. (More? preterm birth)

second stage of labour - passage of the baby through the birth canal into the outside world.

stillbirth and perinatal death - death of a baby after GA 24 weeks of pregnancy but before birth.

tachycardia - rapid fetal heart rate (greater than 160 beats per minute) for the term fetus, usually determined by fetal monitoring.

third stage of labour - interval from the birth of the baby to the expulsion of the placenta and membranes.

tocolytic - a drug used to prevent or lessen uterine contractions.

uterotonic - drug used to induce uterine contractions.

umbilical cord acid-base analysis - clinical perinatal test used to assessing intrapartum hypoxia, measuring one or several indices: arterial umbilical cord blood pH, lactate, and base deficit. Hypoxia is indicated by a low pH, high base deficit and high lactate.

vacuum extractor - (ventouse) rubber or metal suction cap device used on fetal head to aid birth.

vertex presentation - (cephalic presentation) where the fetus head is the presenting part, most common and safest birth position.

Z-score - (standard deviation scores) commonly used to assess growth of preterm infants. For an individual birth weight, a z-score of -1 is one standard deviation below the mean birth weight of the cohort.

z-score differences - (Zdiff) uses standard deviation scores to analyze changes in growth for a particular observation period.

Other Terms Lists
Terms Lists: ART \| Birth \| Bone \| Cardiovascular \| Cell Division \| Endocrine \| Gastrointestinal \| Genital \| Genetic \| Head \| Hearing \| Heart \| Immune \| Integumentary \| Neonatal \| Neural \| Oocyte \| Palate \| Placenta \| Radiation \| Renal \| Respiratory \| Spermatozoa \| Statistics \| Tooth \| Ultrasound \| Vision \| Historic \| Drugs \| Glossary

Glossary: A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Numbers

Cite this page: Hill, M.A. (2024, April 19) Embryology Foundations Practical - Neonatal. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Foundations_Practical_-_Neonatal

What Links Here?

[1] Macaldowie A, Wang YA, Chughtai AA & Chambers GM 2014. Assisted reproductive technology in Australia and New Zealand 2012. Sydney: National Perinatal Epidemiology and Statistics Unit, the University of New South Wales. PDF | eBook

[1]