If you're in the emergency room, and it's a busy night, it's just a busy night. If it's a busy night and there's a full moon, then it's the moon effect. If it's quiet - well, that doesn't count.
Humans are pattern-seeking animals.
Belief in lunar effects on human behavior. Fasi lunari ed incidenza di parti spontanei. To evaluate the relationship between lunar phases and birthrate. These results do not support the hypothesis of a relationship between moon-phase changes and the incidence of spontaneous deliveries. Influenza delle fasi lunari sulla frequenza dei parti.