Brief Answer:
Neonatal sleep myoclonus, a benign condition, to consider.

Detailed Answer:
Hello and welcome to "Ask a Doctor" service.

I have read your query and here is my explanation.

Since the involuntary leg movements (jerks) of your baby are happening only during the sleep, the most likely condition is sleep myoclonus.

Infantile spasm and seizures may happen at any time of the day, night, awake or asleep.

Neonatal sleep myoclonus is considered a benign condition that requires no treatment and should subside with time.

If these involuntary movements, jerks, happen during the wakefulness you should refer these problems to the Pediatrician.

Hope you found the answer helpful.

Let me know if I can assist you further.

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