Lesson 4 — Hormones and the Birthing Process


Self-Check

Check your understanding of parturition and lactation by completing the following questions.

  1. Which hormones are involved in parturition?
  2. What is a Caesarean section?
  3. What is lactation?
  4. Describe the role of oxytocin in lactation.
Did You Know?
Did you know that the greatest number of children born to one Woman is 69? In the 1700s, a woman in Russia reputedly had 16 sets of twins, 7 sets of triplets, and 4 sets of quadruplets! However, this claim was not verified and is assumed to be improbable.

Self-Check Answers


  1. During parturition (birth), estrogen and progesterone levels drop and prostaglandins cause the release of oxytocin. (These two hormones result in uterine contractions.)

  2. A Caesarian section is a surgical procedure in which the mother's abdomen and uterus are opened so that the baby can be delivered when a natural birth is unsafe. (A Caesarian section may be required if the mother has an STI, or if the mother has a small pelvis, or if the baby is in breech position or has the umbilical cord wrapped more than once around its neck.)

  3. Lactation is the formation and secretion of breast milk in the mother.

  4. Oxytocin causes contractions in the mammary lobules, enabling the mother's milk to flow to the milk ducts.

Inquiry into Biology (Whitby, ON: McGraw-Hill Ryerson, 2007), TRM Pg 526. Reproduced by permission.


Going Beyond

Every birth has a possibility of conditions arising that are not typical. There is always a chance that the birthing process will not go exactly according to the plan. Research some of the following terms or phrases in relation to childbirth.

  1. Effacement
  2. Mucus plug
  3. Braxton Hicks contractions
  4. Latent phase
  5. Malpresentation of the fetal head
  6. Being born in the caul
  7. Epidural
  8. Breech
  9. Episiotomy
  10. Apgar score

Biology 30 © 2008  Alberta Education & its Collaborative Partners ~ Updated by ADLC 2019