https://www.jarlife.net/3844-choline-sleep-disturbances-and-...
PEMT (phosphatidylethanolamine N-methyltransferase) is what makes choline in the body, but it depends on estrogen.(https://pmc.ncbi.nlm.nih.gov/articles/PMC3020773/)
https://www.jarlife.net/3844-choline-sleep-disturbances-and-...