Why does labour start at night?

Why is it important to darken the room for a labour? Are candles at a birth just "hippy" or do they help to make birth shorter and more effective?

5 Signs That Your Labor Has Started - FamilyEducation

Can You Go Into Labor While Sleeping? Here's What You Need To Know

Surprising Things That Happen During Labor and Delivery

Pre-Labour - Labour & Childbirth - Huggies AU

Laboring at Night - The Iowa Baby Lady

Evidence for the purple line - Dr Sara Wickham

39 Weeks Pregnant: Symptoms Not to Ignore & Signs of Labour

Laboring at Night - The Iowa Baby Lady

Laboring at Night - The Iowa Baby Lady

What happens during labour & birth :: Healthier Together

Study Reveals What Time of Day Baby Will Likely Be Born