What Happens If You Skip Newborn Screening? The Hidden Risks of Missed Diagnoses

When a baby is born, everything about them seems perfect - ten fingers, ten toes, a strong cry, a healthy heartbeat. But beneath the surface, certain genetic, metabolic, and endocrine conditions may already be present-completely undetectable without proper screening.

For many parents, the idea of a newborn screening test seems optional or even unnecessary, especially if their baby appears healthy. But skipping this test can come at a cost-one that may not show up for weeks, months, or even years. Here’s what you need to know.

The Silent Nature of Most Genetic Conditions

One of the most dangerous assumptions about newborn health is that you’ll see the signs when something is wrong. But many serious conditions are asymptomatic at birth and only reveal themselves after irreversible damage has occurred.

By the time visible symptoms appear - such as seizures, developmental delays, growth failure, or organ dysfunction - the critical window for intervention may have already passed.

Conditions That May Go Undetected Without Screening

Without expanded newborn screening, your baby may miss early diagnosis of conditions such as:

• Phenylketonuria (PKU)-causes brain damage without a strict early diet
• Congenital hypothyroidism- leads to irreversible intellectual disability if untreated
• Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) - can result in sudden death during fasting
• Spinal muscular atrophy (SMA) - requires early therapy for better outcomes
• Severe combined immunodeficiency (SCID) - fatal if untreated in infancy
• Galactosemia, Maple Syrup Urine Disease, Citrullinemia, Biotinidase deficiency-metabolic disorders that can cause seizures, coma, or death if missed

These conditions are rare, but when they do occur, early detection can mean the difference between a healthy life and permanent disability-or even death.

Why Standard Screenings Aren’t Enough

In many countries, including the UK, the NHS currently screens for just 9 conditions-while over 200 serious disorders can now be detected through comprehensive newborn screening.

Many families wrongly assume that if they’ve delivered in a hospital, the baby has been tested for everything. Unfortunately, this false sense of security leads to missed opportunities for diagnosis, especially for rare diseases that aren’t included in standard national panels.

Real Risks of Not Testing

1. Delayed Diagnosis
   Without early screening, diagnosis often only happens after symptoms have worsened-at which point treatment may be less effective or too late.
2. Missed Intervention Windows
   For conditions like congenital hypothyroidism or MCADD, treatment must begin within the first few days or weeks of life to prevent damage. Skipping screening means missing that window.
3. Unnecessary Medical Mystery
   Many families spend months or years seeing specialists and undergoing invasive tests trying to figure out what’s wrong-when one test at birth could’ve given them immediate clarity.
4. Higher Emotional and Financial Burden
   The emotional toll of watching your child suffer without a diagnosis is enormous. It also leads to increased hospitalisations, therapy costs, and long-term care expenses.
5. Preventable Outcomes
   Many conditions detected through newborn screening are treatable-some with nothing more than a dietary change. Not testing means your child may suffer from conditions that were entirely manageable or preventable.

Why Parents Choose Not to Test - And Why That’s Changing

Some parents skip expanded newborn testing because:

• Their baby appears healthy
• They trust the hospital to handle everything
• They worry about cost
• They fear discovering something “bad”

But the cost of not knowing far outweighs the discomfort of facing a diagnosis. With modern screening options like Phenome Longevity’s Comprehensive Newborn Screening Test, early detection is simple, non-invasive, and empowers parents with peace of mind and proactive care.

The Case for Early, Expanded Screening

By screening for over 200 rare but serious conditions using advanced methods like tandem mass spectrometry and DNA analysis, our test gives families the chance to act before problems arise.

Your baby’s health is a lifetime journey. Start with knowledge.

Whether or not a condition is detected, the test gives you reassurance, clarity, and control.

Final Thoughts: What You Don’t Know Can Hurt

Skipping newborn screening doesn’t just mean missing data-it means risking the only chance to detect certain conditions before damage occurs. The early days of life are brief but powerful. They set the tone for your child’s entire future.

Give your baby the strongest foundation by choosing comprehensive newborn screening-because when it comes to your child’s health, not knowing is the greatest risk of all.