Here is the story of Ondine.
In a German tale known as Sleep of Ondine, Ondine is a water nymph. She was very beautiful and, like all nymphs or mermaids, immortal. However, should she fall in love with a mortal man and bear his child, she would lose her immortality.
Ondine eventually falls in love with a handsome knight and they were married. When they exchange vows, he made the vow- “My every waking breath shall be my pledge of love and faithfulness to you.”
A year after their marriage, Ondine gives birth to his child. From that moment on she begins to age. As Ondine\’s physical attractiveness diminishes, the knight loses interest in his wife.
One afternoon, Ondine is walking near the stables when she hears the familiar snoring of her husband. When she enters the stable, she sees her husband naked, lying in the arms of another woman. The scene she encountered filled her with great sorrow. Discarded garments littered the floor and her beloved husband lay sleeping in the haystack, his arms wrapped around his former fiancée. Having sacrificed her immortality for this man, she was filled with anger and regret.
Kicking her sleeping husband, she woke him and uttered her curse. “You pledged faithfulness to me with your every waking breath and I accepted that pledge. So be it. For as long as you are awake, you shall breathe. But should you ever fall into sleep, that breath will desert you.”
Eventually, he fell asleep from sheer exhaustion, and his breathing stopped.
Medical Disorder-not a myth
The tale is the basis for Ondine’s Curse, the historical name for Congenital Central Hypoventilation Syndrome (CCHS), a serious form of central sleep apnea. CCHS causes patients to lose autonomic control of breathing, resulting in the need to consciously initiate every breath. If untreated, patients with CCHS will die–like Ondine’s unfaithful spouse–if they fall asleep and can therefore no longer consciously breathe.
Ondine’s curse is a very rare medical condition characterized by respiratory arrest during sleep. This rare form of apnea may require a patient to be on a ventilator to ensure that the patient is able to breathe while sleeping. Many cases are congenital, with symptoms emerging shortly after birth, although the condition can also be acquired as a result of severe trauma to the brain, as seen in traumatic brain injuries, strokes, and some types of brain tumors.