The heart starts to beat around 6 weeks of gestation.

A human sperm cell contains 23 chromosomes.

There are three stages in human labor: dilation, expulsion, and placental.

The average duration of human gestation is approximately 40 weeks.

The average length of a human newborn at birth is approximately 50 cm.

Progesterone is the primary hormone responsible for maintaining pregnancy.

The typical volume of amniotic fluid at 36 weeks is about 800 mL.

The typical weight range of a full-term newborn is 3-4 kg.