Here's the key: "When constant artificial light plagues a woman's bedroom, her melatonin production becomes limited. This can lead to irregular cycles and unpredictable phases of fertility or infertility. In some cases, this lack of hormones will also shorten the luteal phase, making conception more difficult. When women embrace a more natural pattern of light [sleeping in the dark until it's a full moon], thedir bodies will fall into a comfortable rhythm."
If you try it, let us know what you notice in a comment below!