Christie Clinic - Medicine for Your Life

Our website is currently having technical difficulties. To view the site, please click here

Health Encyclopedia

Health Encyclopedia

An invaluable resource of health information.

related items

Read More
Images

Changes in the newborn at birth

Changes in the newborn at birth are a number of changes that an infant's body undergoes to allow it to survive outside the womb and adapt to life in a new environment.

  • Alternative Names

    Birth - changes in the newborn

  • Information

    LUNGS AND CIRCULATORY SYSTEM

    While the fetus is in the womb, it "breathes" by exchanging oxygen and carbon dioxide through the mother's circulation via the placenta. Most of the blood does not go through the developing baby's lungs. Instead, it travels through the heart and flows throughout the baby's body.

    At birth, the baby's lungs are filled with amniotic fluid and are not inflated. The baby takes the first breath within about 10 seconds after delivery. It sounds like a gasp, as the newborn's central nervous system reacts to the sudden change in temperature and environment.

    Once the umbilical cord is cut and the baby takes the first breath, a number of changes occur in the infant's lungs and circulatory system:

    • Increased oxygen in the lungs causes a decrease in blood flow resistance to the lungs.
    • Blood flow resistance of the baby's blood vessels also increases.
    • Amniotic fluid drains or is absorbed from the respiratory system.
    • The lungs inflate and begin working on their own, moving oxygen into the bloodstream and removing carbon dioxide by breathing out (exhalation).

    TEMPERATURE REGULATION

    A developing baby produces about twice as much heat as an adult. That heat dissipates as blood flows into the mother's circulation via the placenta and is cooled. A small amount of heat is removed through the developing baby's skin, the amniotic fluid, and the uterine wall.

    After delivery, the newborn begins to lose heat. Receptors on the baby's skin send messages to the brain that the baby's body is cold. The baby's body then creates heat by shivering and by burning stores of brown fat, a type of fat found only in fetuses and newborns.

    LIVER

    In the fetus, the liver acts as a storage site for sugar (glycogen) and iron. When the baby is born, the liver has various functions:

    • It produces substances that help the blood to clot.
    • It begins breaking down waste products such as excess red blood cells.
    • It produces a protein that helps break down bilirubin. If the baby's body does not properly break down bilirubin, it can lead to newborn jaundice.

    GASTROINTESTINAL TRACT

    A baby's gastrointestinal system doesn't fully function until after birth.

    In late pregnancy, the fetus produces a tarry green or black waste substance called meconium. Meconium is the medical term for the newborn infant's first stools. Meconium is composed of amniotic fluid, mucous, lanugo (the fine hair that covers the baby's body), bile, and cells that have been shed from the skin and intestinal tract. In some cases, the baby passes stools (meconium) while still inside the uterus.

    URINARY SYSTEM

    The developing baby's kidneys begin producing urine by 9 - 12 weeks into the pregnancy. After birth, the newborn will usually urinate within the first 24 hours of life. The kidneys become able to maintain the body's fluid and electrolyte balance.

    The rate at which blood filters through the kidneys (glomerular filtration rate) increases sharply after birth and in the first 2 weeks of life. Still, it takes some time for the kidneys to get up to speed. Newborns have less ability to remove excess salt (sodium) or to concentrate or dilute the urine compared to adults. This ability improves over time.

    IMMUNE SYSTEM

    The immune system begins to develop in the fetus, and continues to mature through the child's first few years of life. The womb is a relatively sterile environment. But as soon as the baby is born, he or she is exposed to a variety of bacteria and other potential disease-causing substances. Although newborn infants are more vulnerable to infection, their immune system can respond to infectious organisms.

    Newborns do carry some antibodies from their mother, which provide protection against infection. Breastfeeding also helps improve a newborn's immunity.

    SKIN

    Newborn skin will vary depending on the length of the pregnancy. Premature infants have thin, transparent skin. The skin of a full-term infant is thicker.

    Characteristics of newborn skin:

    • A fine hair called lanugo might cover the newborn's skin, especially in preterm babies. The hair should disappear within the first few weeks of the baby's life.
    • A thick, waxy substance called vernix may cover the skin. This substance protects the fetus while floating in amniotic fluid in the womb. Vernix should wash off during the baby's first bath.
    • The skin might be cracking, peeling, or blotchy, but this should improve over time.

    See: Skin characteristics in newborns for other skin changes in the newborn.

  • References

    Olsson J. The newborn. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 7.

Review Date: 11/2/2009

Reviewed By: Neil K. Kaneshiro, MD, MHA, Clinical Assistant Professor of Pediatrics, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. © 1997- 2014 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
adam.com
Christie Clinic at the Family Medical Center in Paris
727 East Court Street Paris, IL 61944 Dermatology: 366-1248; Vein and Vascular: 366-2670
Christie Clinic Christie Clinic on University Photo Christie Clinic on University
101 West University Avenue Champaign, IL 61820 Main Phone: (217) 366-1200
Billing Services: (217) 366-1382
Toll Free: (888) 391-0412
Christie Clinic Christie Clinic on Windsor/Convenient Care Photo Christie Clinic on Windsor/Convenient Care
1801 West Windsor Road Champaign, IL 61822 (217) 366-8000
Christie Clinic Christie Clinic at Presence Covenant Photo Christie Clinic at Presence Covenant
1400 West Park Street Urbana, IL 61801 (217) 366-1200
Christie Clinic Christie Clinic in Rantoul Photo Christie Clinic in Rantoul
209 West Borman Drive Rantoul, IL 61866 (217) 892-9671
Christie Clinic Christie Clinic in Mahomet/Convenient Care Photo Christie Clinic in Mahomet/Convenient Care
1001 Commercial Drive Mahomet, IL 61853 Main Number: (217) 586-6600 Convenient Care: (217)366-8130
Christie Clinic Christie Clinic in Danville on Vermilion/Convenient Care Photo Christie Clinic in Danville on Vermilion/Convenient Care
3545 North Vermilion Street Danville, IL 61832 (217) 442-8611
Christie Clinic Christie Clinic in Tuscola Photo Christie Clinic in Tuscola
300 North Main Street Tuscola, IL 61953 (217) 253-9258
Christie Clinic CU Sleep Photo CU Sleep
1207 South Mattis Avenue Champaign, IL 61821 (217) 355-1684
Christie Clinic Christie Clinic Cancer Center Photo Christie Clinic Cancer Center
109 West University Avenue Champaign, IL 61820 (217) 366-5180
Christie Clinic Convenient Care in County Market (Kirby & Duncan) Photo Convenient Care in County Market (Kirby & Duncan)
2901 West Kirby Avenue Champaign, IL 61821 (217) 366-8130
Christie Clinic Christie Clinic in Urbana/Convenient Care Photo Christie Clinic in Urbana/Convenient Care
1710 East Windsor Road Urbana, IL 61802 (217) 344-9440
Christie Clinic Christie Clinic in Danville on Logan Photo Christie Clinic in Danville on Logan
800 North Logan Avenue Danville, IL 61832 (217) 431-8930
Christie Clinic Christie Clinic on Fox Drive Photo Christie Clinic on Fox Drive
2110 Fox Drive, Suite B Champaign, IL 61820
Christie Clinic Christie Clinic in Monticello at Kirby Medical Group Specialty Clinic Photo Christie Clinic in Monticello at Kirby Medical Group Specialty Clinic
1109 B North State Street Monticello, IL 61856 (217) 366-1304
Gibson Area Hospital
1120 N Melvin Gibson City, IL 60936 (217) 784-2240
Christie Clinic Christie Clinic in Mattoon Photo Christie Clinic in Mattoon
105 B Professional Plaza Mattoon, IL 61938 (217) 345-3000
Christie Clinic Sarah Bush Lincoln Health System Photo Sarah Bush Lincoln Health System
1000 Health Center Drive Mattoon, IL 61938 (217) 258-2588
Christie Clinic The Champaign SurgiCenter Photo The Champaign SurgiCenter
1702 S. Mattis Avenue Champaign, IL 61821 (217) 326-2030
Christie Clinic The Carle Foundation Hospital Photo The Carle Foundation Hospital
611 West Park Street Urbana, IL 61801 (217) 383-3311
Iroquois Memorial Hospital
200 E. Fairman Ave. Watseka, IL 60970 (815) 432-5841
Christie Clinic Christie Clinic in Savoy Photo Christie Clinic in Savoy
501 North Dunlap Avenue Savoy, IL 61874 Transformations: (217) 366-7460 Internal Medicine: (217) 366-5434 Ophthalmology: (217) 366-1250
Christie Clinic on West Park Street
1405 West Park Street Urbana, IL 61801 217-366-1237
Christie Clinic in Monticello
107 West Main Street Monticello, IL 61856 217.762.3352
Christie Clinic Christie Clinic in Decatur Photo Christie Clinic in Decatur
100 South Water Street Suite 103 Decatur, IL 62523 217-362-0661- telephone