MRCOG Part 1: Endocrinology - Essential Study Guide

This is your essential guide to the Endocrinology section of the MRCOG Part 1 exam. We built it from our own experience of sitting the exam, the RCOG syllabus and the official reading list. It lists the endocrinology concepts most often tested, section by section.

Why Endocrinology matters in MRCOG Part 1

Endocrinology is a crucial subject for the MRCOG Part 1 exam as it covers the hormonal regulation of reproductive processes, pregnancy, and the fetal-maternal unit. A thorough understanding of endocrine systems is essential for diagnosing and managing various conditions in obstetrics and gynaecology.

Endocrinology syllabus, section by section

IHypothalamus and Pituitary Gland

Anterior Pituitary Hormones

Growth Hormone (GH)
  • Regulation of secretion (GHRH, somatostatin)
  • Metabolic effects (protein, fat, carbohydrate metabolism)
  • Role of IGF-1
  • Acromegaly: causes, clinical features, diagnosis, and management
Prolactin (PRL)
  • Regulation of secretion (dopamine, TRH)
  • Physiological roles
  • Hyperprolactinaemia: causes (including prolactinoma), clinical features, and management
Gonadotrophins (FSH, LH)
  • Regulation of secretion (GnRH)
  • Roles in the ovarian and menstrual cycles
  • Roles in spermatogenesis
  • Clinical significance of gonadotrophin levels

Posterior Pituitary Hormones

Arginine Vasopressin (AVP)
  • Regulation of secretion (osmolality, blood volume)
  • Actions on water balance and blood pressure
  • Diabetes insipidus: central vs. nephrogenic, diagnosis, and management
Oxytocin (OXY)
  • Roles in lactation and parturition
  • Clinical uses in obstetrics

IIPlacental Structure and Function

Placental Hormones

Human Chorionic Gonadotrophin (hCG)
  • Structure and function
  • Role in maintaining the corpus luteum
  • Clinical uses (pregnancy tests, monitoring of molar pregnancy)
Progesterone
  • Source during pregnancy (corpus luteum, placenta)
  • Roles in maintaining pregnancy
Estrogen (Oestrogen)
  • Synthesis and source during pregnancy
  • Clinical significance of oestrogen levels
Human Placental Lactogen (hPL)
  • Role in modifying maternal metabolism
  • Relationship to gestational diabetes

Placental Development and Function

Implantation and trophoblast invasion
  • Mechanism of adhesion and penetration
Formation of the intervillous space
  • Development of primary, secondary and tertiary stem villi
Types of placentation
  • Epitheliochorial, endotheliochorial, haemochorial
Maternal-fetal exchange
  • Mechanisms of transport (diffusion, active transport)
  • Transport of oxygen, carbon dioxide, glucose, amino acids, water, and electrolytes

Immunology of Pregnancy Tolerance

Role of uterine NK cells
  • Characteristics of uterine NK cells
Placenta-uterus immune interaction
  • Role of HLA-C, HLA-G and HLA-E molecules

IIIAdrenal and Thyroid Glands and the Pancreas

Adrenal Gland

Adrenal Cortex
  • Steroid synthesis pathway
  • Regulation of cortisol secretion (ACTH, CRH, circadian rhythm)
  • Actions of glucocorticoids
  • Regulation of aldosterone secretion (renin-angiotensin system, potassium)
  • Actions of mineralocorticoids
  • Adrenal androgens (DHEA, androstenedione)
Adrenal Medulla
  • Catecholamine synthesis and secretion
  • Actions of catecholamines
  • Phaeochromocytoma: clinical features, diagnosis, and management
Adrenal Disorders
  • Cushing syndrome: causes, clinical features, diagnosis, and management
  • Primary aldosteronism: causes, clinical features, diagnosis, and management
  • Adrenal insufficiency (Addison's disease): causes, clinical features, diagnosis, and management
  • Congenital adrenal hyperplasia: causes, clinical presentation, diagnosis, and management

Thyroid Gland

Thyroid Hormone Synthesis and Secretion
  • Iodine uptake and organification
  • Formation of T3 and T4
  • Role of TSH
  • Transport and metabolism of thyroid hormones
Actions of Thyroid Hormones
  • Effects on metabolism, growth, and development
Thyroid Disorders
  • Hyperthyroidism: causes (Graves disease, toxic multinodular goitre, toxic adenoma), clinical features, diagnosis, and management
  • Hypothyroidism: causes (Hashimoto thyroiditis, iodine deficiency), clinical features, diagnosis, and management
  • Thyroid disorders in pregnancy (gestational hyperthyroidism, gestational hypothyroidism, postpartum thyroiditis)
  • Management of thyroid nodules in pregnancy

Endocrine Pancreas

Insulin
  • Synthesis and secretion
  • Actions on target tissues (liver, muscle, adipose tissue)
  • Regulation of secretion
Glucagon
  • Synthesis and secretion
  • Actions on the liver
  • Regulation of secretion
Other Pancreatic Hormones
  • Somatostatin
  • Vasoactive Intestinal Peptide
  • Gastrin
Diabetes Mellitus
  • Type 1 diabetes: pathophysiology, clinical features
  • Type 2 diabetes: pathophysiology, clinical features
  • Gestational diabetes mellitus: pathophysiology, clinical features, diagnosis, management, and long-term implications
  • Treatment of diabetes mellitus (insulin, oral hypoglycaemic agents)
  • Diabetic complications (microvascular, macrovascular)
  • Endocrine tumours of the pancreas (insulinoma, gastrinoma, glucagonoma, VIPoma, somatostatinoma)
Endocrine Pancreas and Pregnancy
  • Changes in glucose metabolism during pregnancy
  • Changes in lipid metabolism during pregnancy

IVOvarian Function and Disorders

Ovarian Hormones

Oestrogen
  • Synthesis and sites of production
  • Actions on reproductive tissues
  • Role in the menstrual cycle
Progesterone
  • Synthesis and sites of production
  • Actions on reproductive tissues
  • Role in the menstrual cycle
Androgens
  • Synthesis and sites of production in the ovary
  • Role in female physiology

Ovarian Disorders

Premature Ovarian Failure
  • Causes (genetic, autoimmune, iatrogenic)
  • Clinical presentation
  • Diagnosis
  • Management
Polycystic Ovary Syndrome (PCOS)
  • Diagnostic criteria
  • Hormonal imbalances
  • Clinical features (menstrual irregularities, hirsutism, infertility)
  • Long-term health risks
  • Management

Puberty and Menopause

Physiology of Puberty
  • Hormonal changes
  • Development of secondary sexual characteristics
  • Precocious puberty
  • Delayed puberty
Menopause
  • Hormonal changes
  • Clinical features
  • Management of menopausal symptoms

How to master Endocrinology

  • Review: work through each section systematically and understand the core concepts before moving on.
  • Active learning: draw diagrams, build mind maps and explain concepts to someone else.
  • Test yourself: try our free practice questions, then work through the endocrinology questions in the Uterio question bank.

Additional resources