Newborn Screening Tests

Each newborn baby is carefully checked at birth for signs of problems or complications. The healthcare provider will do a complete physical exam that includes every body system. Throughout the hospital stay, doctors, nurses, and other healthcare providers continually look at the health of the baby. They are watching for signs of problems or illness. Assessments may include the following:

Apgar Scoring

The Apgar score helps find breathing problems and other health issues. It is part of the special attention given to a baby in the first few minutes after birth. The baby is checked at 1 minute and 5 minutes after birth for heart and respiratory rates, muscle tone, reflexes, and color.

Each area can have a score of 0, 1, or 2, with 10 points as the maximum total. Most babies score 8 or 9, with 1 or 2 points taken off for blue hands and feet because of immature circulation. If a baby has a difficult time during delivery and needs extra help after birth, this will be shown in a lower Apgar score. Apgar scores of 6 or less usually mean a baby needs immediate attention and care.

Birth weight

A baby’s birth weight is an important marker of health. Full-term babies are born between 37 and 41 weeks of pregnancy. The average weight for full-term babies is about 7 pounds (3.2 kg). In general, very small babies and very large babies are at greater risk for problems. Babies are weighed every day in the nursery to look at growth, and the baby’s need for fluids and nutrition. Newborn babies may often lose 5% to 7% of their birth weight. This means that a baby weighing 7 pounds, 3 ounces at birth might lose as much as 8 ounces in the first few days. Babies will usually gain this weight back within the first 2 weeks after birth. Premature and sick babies may not begin to gain weight right away.

Measurements

The hospital staff takes other measurements of each baby. These include:

  • Head circumference – This is the distance around the baby’s head.
  • Chest Circumference – This is the distance around the baby’s chest.
  • Length – This is the measurement from top of head to the heel.

The staff also checks these vital signs:

  • Temperature – This checks that the baby is able to have a stable body temperature in a normal room environment.
  • Pulse – A newborn’s pulse is normally 120 to 160 beats per minute.
  • Breathing rate – A newborn’s breathing rate is normally 40 to 60 breaths per minute.

Physical Exam

A complete physical exam is an important part of newborn care. The healthcare provider carefully checks each body system for health and normal function. The provider also looks for any signs of illness or birth defects. Physical exam of a newborn often includes:

  • General appearance – This looks at physical activity, muscle tone, posture, and level of consciousness.
  • Skin – This looks at skin color, texture, nails, and any rashes.
  • Head and neck – This looks at the shape of head, the soft spots (fontanelles) on the baby’s skull, and the bones across the upper chest (clavicles).
  • Face – This looks at the eyes, ears, nose, and cheeks.
  • Mouth – This looks at the roof of the mouth (palate), tongue, and throat.
  • Lungs – This looks at the sounds the baby makes when they breathe. This also looks at the breathing pattern.
  • Heart sounds and pulses in the groin (femoral)
  • Abdomen – This looks for any masses or hernias.
  • Genitals and anus – This checks that the baby has open passages for urine and stool.
  • Arms and legs – This checks the baby’s movement and development.

Gestational Assessment

The healthcare provider will check how mature the baby is. This is an important part of care. This check helps figure out the best care for the baby if the dates of a pregnancy are uncertain. For example, a very small baby may actually be more mature than they appear by size and may need different care than a premature baby needs.

Healthcare providers often use an exam called the Dubowitz/Ballard Examination for Gestational Age. This exam can closely estimate a baby’s gestational age. The exam looks at a baby’s skin and other physical features, plus the baby’s movement and reflexes. The physical maturity part of the exam is done in the first 2 hours of birth. The movement and reflexes part of the exam is done within 24 hours after birth. The provider often uses the information from this exam to help with other maturity estimates.

Physical Maturity

The physical maturity part of the Dubowitz/Ballard exam looks at physical features that look different at different stages of a baby’s gestational age. Babies who are physically mature usually have higher scores than premature babies.

Points are given for each area of assessment. A low of 1 or 2 means that the baby is very immature. A score of 4 or 5 means that the baby is very mature (postmature). These are the areas examined:

  • Skin textures – Is the skin sticky, smooth, or peeling?
  • Soft, downy hair on the baby’s body (lanugo) – This hair is not found on immature babies. It shows up on a mature infant but goes away for a postmature infant.
  • Plantar creases – These are creases on the soles of the feet. They can range from absent to covering the entire foot.
  • Breast – The provider looks at the thickness and size of breast tissue and the darker ring around each nipple (areola).
  • Eyes and ears – The provider checks to see if the eyes are fused or open. They also check the amount of cartilage and stiffness of the ears.
  • Genitals, male – The provider checks for the testes and how the scrotum looks. It may be smooth or wrinkled.
  • Genitals, female – The provider checks the size of the clitoris and the labia and how they look.

Maturity of Nerves and Muscles

The healthcare provider does 6 checks of the baby’s nerves and muscles. A score is given for each area. Typically, the more mature the baby is, the higher the score. These are the areas checked:

  • Skin textures – This looks at how the baby holds their arms and legs.
  • “Square window” – This looks at how far the baby’s hands can be flexed toward the wrist.
  • Arm recoil – This looks at how much the baby’s arms “spring back” to a flexed position.
  • Popliteal angle – This looks at how far the baby’s knees extend.
  • “Scarf sign” – This looks at how far the baby’s elbows can be moved across the baby’s chest.
  • Heel to ear – This looks at how near the baby’s feet can be moved to the ears.

When the physical assessment score and the nerves and muscles score are added together, the healthcare provider can estimate the baby’s gestational age. Scores range from very low for immature babies to very high scores for mature and postmature babies.

All of these exams are important ways to learn about your baby’s well-being at birth. By finding any problems, your baby’s healthcare provider can plan the best possible care.