Newborn Tests and Assessments After Birth

During your baby’s hospital stay, a series of routine tests and medical assessments are performed to help ensure your newborn is healthy and adjusting well after birth. These screenings are standard for all babies and are completed by your care team, which may include a neonatologist or pediatrician.

Many of these tests are required by the state of California and are designed to detect conditions that may not be visible at birth. Early identification allows for timely follow-up and, when needed, early treatment and support.

Newborn Physical Assessment

Shortly after birth and throughout your hospital stay, your baby will receive regular physical assessments. These exams help evaluate your baby’s overall health and development.

As part of the newborn exam, your provider will:

• Listen to your baby’s heart and lungs with a stethoscope
• Check breathing, heart rate, muscle tone, and reflexes
• Examine your baby’s head, eyes, ears, mouth, abdomen, hips, spine, and skin
• Monitor feeding, weight, and vital signs

These assessments are repeated as needed to ensure your baby is transitioning well outside the womb.

California Newborn Screening Test (Blood Spot Test)

All newborns in California receive a state-mandated newborn screening test. This blood test screens for a number of rare but serious metabolic, genetic, and hormonal conditions that may not be apparent at birth.

The test is performed using a small heel prick, typically within the first 24 to 48 hours after birth. A few drops of blood are collected and sent to a specialized newborn screening laboratory for analysis. Conditions screened for may include phenylketonuria (PKU), congenital hypothyroidism, cystic fibrosis, and other metabolic disorders.

Most babies have normal results. If a screening result is outside the expected range, your care team will contact you to explain next steps and arrange follow-up testing if needed.

Newborn Hearing Screening

Newborn hearing screening is a routine and important part of newborn care. This test checks how your baby’s auditory system responds to sound and helps identify possible hearing loss early, before signs are noticeable.

The screening is quick, painless, and usually performed while your baby is sleeping. Soft earphones and sensors are used to measure how sound signals travel through the ear and brain. If your baby does not pass the initial screening, it does not necessarily mean there is permanent hearing loss, but follow-up testing will be recommended to ensure accurate results.

Early detection of hearing differences allows for early intervention, which supports speech, language, and developmental milestones.

Pulse Oximetry Screening (Critical Congenital Heart Disease)

Pulse oximetry is a safe, non-invasive test used to screen for certain types of congenital heart disease that may not be detected during pregnancy or physical exam alone.

During this screening, a small sensor is gently placed on your baby’s hand and foot for a few minutes to measure oxygen levels in the blood. Low oxygen levels may indicate a heart condition or another medical issue that requires further evaluation.

Early detection through pulse oximetry can improve treatment outcomes and help prevent serious complications.

Bilirubin Check (Jaundice Screening)

Bilirubin is a natural byproduct of red blood cell breakdown. Because a newborn’s liver is still developing, bilirubin can sometimes build up in the blood and cause jaundice, which appears as yellowing of the skin or eyes.

As part of routine newborn care, bilirubin levels are checked using a blood sample or non-invasive skin scan. This screening helps identify babies who may be at risk for high bilirubin levels and need closer monitoring or treatment.

Most newborn jaundice is mild and temporary. More detailed information about jaundice, monitoring, and treatment is available on our Newborn Jaundice page.

How Results Are Shared With Families

Your care team will review test results with you during your hospital stay whenever possible. Before discharge, screening results and any recommended follow-up will be documented in your baby’s medical record and shared with your baby’s pediatrician.

If additional testing or follow-up appointments are needed, your team will help coordinate next steps and answer your questions.

After Discharge: Ongoing Monitoring

Even when all newborn screenings are normal, your baby’s pediatrician will continue to monitor growth, development, hearing, and overall health during well-child visits. If you have concerns at any time — including feeding issues, lack of response to sound, or changes in skin color — contact your baby’s provider.

Supporting a Healthy Start

Newborn tests and assessments are an important part of giving your baby a healthy start. These screenings are designed to provide reassurance, identify concerns early, and connect families with care and resources when needed.

If you have questions about any test or screening, your care team is always available to help.