Understanding a First-Time Autism Diagnosis in Adulthood

by Dr. Craig Kerley, Psy.D.

Understanding a First-Time Autism Diagnosis in Adulthood

Receiving a diagnosis of Autism Spectrum Disorder (ASD) as an adult can be a profoundly validating—and sometimes overwhelming—experience. Many adults come to an autism diagnosis later in life after years of navigating the world feeling “different,” misunderstood, or exhausted from masking their internal experiences. Whether the diagnosis follows personal research, the recommendation of a therapist, or the pursuit of answers after a child’s diagnosis, the process often brings clarity, relief, and new questions.

In this blog post, we’ll explore what it means to be diagnosed with autism as an adult, why the diagnosis might be missed earlier in life, and how you can begin to make sense of this new understanding of yourself.

Why Are Some Diagnoses Missed Until Adulthood?

 Autism can present in a wide variety of ways, particularly among individuals who have learned to mask or camouflage their symptoms. Historically, autism was underdiagnosed in females and in people with average or above-average intelligence who developed language skills on time. These individuals often developed strong compensatory strategies, sometimes at the cost of chronic stress or burnout.

Common reasons a diagnosis may be missed until adulthood include:

• Subtle social difficulties masked by mimicking peers

• Sensory sensitivities mistaken for “quirks”

• Intense interests labeled as “passions” or “eccentricities”

• Misdiagnosis with anxiety, ADHD, or personality disorders

• Gender-based diagnostic bias

• Lack of awareness about autism in earlier decades

Emotional Reactions to a New Diagnosis

Adults who receive a diagnosis of autism often experience a mix of emotions. Some common responses include:

• Relief: “Now I understand why I’ve always felt this way.”

• Grief: Mourning the challenges, missed supports, or social difficulties of earlier years.

• Confusion: Reassessing long-held beliefs about oneself.

• Validation: Feeling seen and understood for the first time.

• Hope: Looking forward to learning more about your needs and how to meet them.

These reactions are normal and valid. It’s okay to take time to process the information at your own pace.

What Changes After a Diagnosis? 

While your core personality doesn’t change, having a diagnosis can provide a new framework for self-understanding. It may help:

• Reframe past experiences with greater compassion

• Understand why certain environments or relationships were more difficult

• Guide decisions about work, relationships, and self-care

• Inform access to accommodations or services

Some adults choose to share their diagnosis with family, friends, or employers. Others may keep it private. There is no right or wrong choice—what matters most is what feels right for you.

Seeking Support 

Therapy can be a helpful place to explore your thoughts and feelings around a new diagnosis. A clinician familiar with adult autism can support you in areas such as:

• Navigating identity shifts

• Building sensory-friendly routines

• Understanding relationships and social boundaries

• Learning to advocate for your needs

Many adults also find connection and insight through books, podcasts, online communities, and support groups focused on neurodiversity.

Final Thoughts

A first-time autism diagnosis in adulthood is not the start of your journey—it’s a deeper understanding of the path you’ve already been on. Embracing that identity with curiosity and self-compassion can lead to growth, healing, and a more authentic way of living.

If you’re navigating this experience and looking for support, our practice is here to help. We provide neurodiversity-affirming evaluations and therapy tailored to the unique experiences of adults on the autism spectrum.

You are not alone—and there is strength in knowing yourself more fully.

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