Chapter 3 – Endocrinology

1. Read Coad, Anatomy & Physiology for Midwives, 4th edition, chapter 3.
2. Write out your answers to Coad, Chapter Case Study, page 66.
3. Create a Coad “Chapter 3 Study Sheet.” Include the following:

Learning Goals

□ Explain what endocrinology is.

□ Describe how hormones communicate with target tissues.

□ Compare the endocrine and nervous systems.

□ Identify the major endocrine glands and the hormones they produce.

□ Describe the major classes of hormones.

□ Explain the role of sex steroids.

□ Explain how hormones regulate reproduction.

□ Explain how hormones and hormone-like medications are used in maternity care.

Essential Vocabulary

Basic Terms

• Endocrinology
• Endocrine gland
• Hormone
• Target cell
• Receptor
• Neurotransmitter
• Neurohormone
• Feedback loop
• Homeostasis

Hormone Types

• Steroid hormone
• Peptide hormone
• Protein hormone
• Amino acid derivative

Reproductive Hormones

• GnRH
• FSH
• LH
• Estrogen
• Progesterone
• hCG
• Prolactin
• Oxytocin
• Relaxin
• hPL (Human Placental Lactogen)

Draw

Major endocrine glands

Draw and label:

• Hypothalamus
• Pituitary
• Thyroid
• Parathyroids
• Adrenals
• Pancreas
• Ovaries
• Testes
• Placenta (during pregnancy)

Hormone pathway

Draw:

Hypothalamus

↓

Pituitary

↓

Target gland

↓

Hormone

↓

Target tissue

↓

Negative feedback

Structures I Must Know

Hormones I Must Know

Rather than memorizing lists, understand the story.

Processes I Must Understand

• Hormone production
• Hormone transport
• Hormone receptors
• Negative feedback
• Positive feedback
• Hypothalamic-pituitary axis
• Menstrual hormonal cycle (overview)
• Pregnancy endocrine changes

Midwifery Connections

Clinical Connections

Understand why:

• Labor begins when hormonal balance changes.
• Synthetic oxytocin can induce or augment labor.
• Misoprostol and prostaglandins ripen the cervix.
• hCG is measured in early pregnancy.
• Thyroid disorders affect pregnancy.
• Diabetes is fundamentally an endocrine disorder.
• Hyperemesis may have hormonal contributors.
• Placenta functions as a major endocrine organ.

Things Worth Memorizing

• Major endocrine glands
• Major reproductive hormones
• Hormone source
• Primary action of each hormone
• Difference between endocrine and nervous systems
• Difference between steroid and peptide hormones

This table comparing the nervous and endocrine systems is especially worth remembering. It summarizes a core concept you’ll encounter throughout the book:

Questions I Should Answer Without Looking

1. What is a hormone?
2. How does the endocrine system differ from the nervous system?
3. What is a target cell?
4. How does negative feedback regulate hormones?
5. Which gland is called the “master gland”?
6. Which hormone maintains early pregnancy?
7. Which hormone causes uterine contractions?
8. Which hormone stimulates milk production?
9. Which hormone causes milk let-down?
10. Why is the placenta considered an endocrine organ?

Quick Reference Cards

Chapter 3 naturally lends itself to several stand-alone cards that you’ll revisit often:

• Hormones of Pregnancy
• Oxytocin
• Prolactin
• Estrogen
• Progesterone
• hCG
• Relaxin
• Endocrine vs. Nervous System
• Anterior vs. Posterior Pituitary Hormones
• Placenta as an Endocrine Organ

One addition I’d make for your long-term system

Because hormones appear throughout obstetrics, I’d add a “Hormone Profile” template to your compendium. For every major hormone, record the same information:

• Produced by:
• Target tissues:
• Primary actions:
• Role in pregnancy:
• Role in labor:
• Role postpartum:
• Clinical relevance (too high/too low):
• Related medications (if any):

Using the same format for every hormone will make later chapters—such as pregnancy physiology, labor, lactation, thyroid disease, gestational diabetes, and infertility—much easier to integrate into one coherent reference.