Month

It doesn't contains any moon cycle in Glorantha. Lunar, Eastern and Malkioni Calendar shares the concept of Month, though units are all different.

Lunar Calendar
Lunar Month consists of four weeks, twenty-eight days. Annual months are ten, called: Innocence, Glamour, Anticipation, Ascension, Zenith, Change, Descent and Moonset. Lunar Calendar has Sacred Time, thus ten months occupy all normal two-hundred and eighty days.

Eastern Calendar
Eastern Month consists of seven weeks, fourteen-nine days. Annual months are six, named after the six ancestral dragons: Silence, Secret, Being, Experience, Thought and Spirit. Eastern Calendar doesn't have the concept of Sacred Time.

Malkioni Calendar
Malkioni Month consists of four weeks (exactly half of the Theyalan Calandar season), Annual months are ten, called Sementis, Vernus, Fervidor, Aestival, Messistide, Aeror, Frigidor, Brumastide, Turbidor ans Nex. Malkioni Calendar also has Sacred Time, thus ten months occupy all normal two-hundred and eighty days.

Note
I suggest women menstruation cycle can be explained from the planetary cycle of the White Planet rather than that of any moons in Glorantha