The Moro Reflex is plays a vital role in allowing babies to take their first breath. The sudden change of temperature, bright lights, and overall stimulation ensures the baby uses its lungs for the first time. 
What are reflexes?
Reflexes are critical for survival as they are "the blueprint for overall movements by teaching muscles to work together and against gravity." These first reflexes develop when your baby is still in your belly. They are called "primitive reflexes". "Once a reflex has done its job it integrates into the hindbrain allowing for a more purposeful, sophisticated movement to develop. This series of developmental movements, built one on top of another, creates the foundational building blocks for all movement and subsequent interaction with our world."  Different kinds of reflexes correspond to different parts of the body, as well as mental health. The Fear Paralysis and Moro reflexes relate to perceived self-preservation and emotional well-being.
What is the Moro Reflex?
The Moro Reflex replaces the Fear Paralysis Reflex. It is often referred as the Startle Reflex. "The startle reflex is the baby's response to the sensation of falling and/or stimuli in their environment, such as loud, potentially threatening sounds and bright lights. Babies who hear loud sounds may also experience effects their parents can’t see, such as an increased heartbeat or heavy breathing. Some babies are more sensitive than others and will react with more intensity and more often."  The Moro Reflex should disappear around 2 months of age. You should consult pediatrician if your baby Moro Reflex is still active when they are 6 months old.
Symptoms of a retained Moro Reflex
"A child with a retained Moro reflex demonstrates many of the following problems: difficulty focusing, distractibility, poor impulse control, emotional immaturity & sensitivity, mood swings, anxiety, easily triggered anger, difficulty performing different types of eye movements, difficulty ignoring irrelevant visual material, tense muscle tone, difficulty reading black print on white paper, tiring under fluorescent lighting, difficulty ignoring background noise, trouble understanding differences between sounds, aggressiveness or withdrawal, balance issues, difficulty with math, decreased coordination (usually during ball-sports), dislike of tags in clothing & certain textures, difficulty accepting criticism, low stamina/endurance, dislike of change, motion sickness, food sensitivities, different responses to drugs & medications, controlling or manipulative behaviors, low self-esteem, difficulty making decisions, and hyperactivity followed by fatigue."  The Moro Reflex is connected to the adrenal glands that are a large part of our immune system. Having them constantly activated can lead to adrenal fatigue, asthma, allergies, and chronic illness.
How to test for a retained Moro Reflex?
The Moro Reflex is easy to test for by simulating unexpecting falling. If you let your baby’s head free fall for an inch or two, they will throw out their arms, flex their hands, then cry. Next, they will pull themselves into a fetal position and relax. "If your baby is a preemie, the timing of their startle reflex may be different than is typical for full-term infants. The reflex's onset may be delayed and the reflex may stick around longer than normal due to the gap between your baby's birthday and their developmental age" 
What can you do about a retained Moro Reflex?
Active primitive reflexes can have life long affects. So what can you do about it? Awareness is the first step in prevention. Now that you know that a retained Moro reflex can cause life long issues, you can monitor your baby's behavior. If you think that it is still active, make an appointment with your pediatrician. If they determine that your baby has any lingering reflexes, they will give you a referral to a specialist. Then meet with a pediatric occupational therapist, or therapist depending on their needs. Early intervention is the most valuable thing that you can do to help your baby.
Leanne Davis, "Understanding the impact of retained primitive reflexes on emotional and mental health", Sep 24, 2021, https://www.thekeyclinic.co.uk/post/understanding-the-impact-of-retained-primitive-reflexes-on-emotional-and-mental-health
Stephanie Brown, "The Moro Reflex in Newborn Babies", Very Well Family, January 20, 2021, https://www.verywellfamily.com/learn-more-about-the-startle-reflex-in-newborn-babies-290102
Jerilyn Lecce, Occupational Therapist, "Retained Primitive Moro Reflex Effect On Development", Intermountain Caring Solutions, April 5, 2018, https://www.intermountain.org/retained-primitive-moro-reflex-effect-on-development/
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