RUHS, Jaipur, PB B.Sc Nursing Entrance-2021
Obstetrics & Gynaecology
Easy

Hormones are responsible for milk ejection is ?

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2021

Explanation

  • Oxytocin is the hormone responsible for the milk ejection reflex, also known as the let-down reflex.
  • It is released from the posterior pituitary gland in response to stimuli like the baby suckling the nipple.
  • Oxytocin acts on the myoepithelial cells surrounding the alveoli of the mammary glands, causing them to contract.
  • This contraction forces the milk from the alveoli into the ducts, making it available for the infant to drink.

Why Other Options Were Wrong

  • Option A: FSH (Follicle-Stimulating Hormone) is a gonadotropic hormone from the anterior pituitary. Its primary function is to stimulate the growth of ovarian follicles in women and sperm production in men. It is not involved in lactation.
  • Option B: Testosterone is the primary male sex hormone (androgen). It is responsible for the development of male reproductive tissues and secondary sexual characteristics. It plays no role in milk ejection.
  • Option C: Progesterone is essential for preparing the uterus for pregnancy and maintaining it. During pregnancy, high levels of progesterone inhibit the full secretory activity of the breasts. A sharp drop in progesterone after delivery is one of the triggers for milk production to begin, but it does not cause milk ejection.

Related Visual

An illustration of the milk ejection reflex. It should show a cross-section of the breast with alveoli and ducts, the infant suckling, the neural pathway from the nipple to the...
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Hormonal control of lactation, specifically the milk ejection reflex as background academic context rather than a clinical decision trigger.
  • Understanding the milk ejection reflex is crucial for nurses counseling new mothers on breastfeeding.
  • Nurses can explain that factors like stress, pain, or anxiety can inhibit the release of oxytocin, leading to difficulty with milk let-down. Relaxation techniques, a comfortable environment, and privacy can facilitate the reflex.
  • Synthetic oxytocin (e.g., Syntocinon nasal spray) can be prescribed in some cases to help stimulate the let-down reflex if a mother is having difficulty.
How to Approach the Question
  • First, identify the key physiological process in the question: 'milk ejection'.
  • Differentiate this specific process from the related but distinct process of 'milk production' (synthesis).
  • Recall the primary hormones involved in lactation. Prolactin is for production, and Oxytocin is for ejection.
  • Evaluate the given options. FSH, Testosterone, and Progesterone are primarily involved in the reproductive cycle and pregnancy maintenance, not milk ejection.
  • Select Oxytocin as the hormone directly responsible for causing the myoepithelial cells to contract and eject milk.
Concept Tested & Keywords
  • Concept Tested: Hormonal control of lactation, specifically the milk ejection reflex.
  • Stem keywords: Hormone, milk ejection
  • Lead-in keywords: responsible for
  • Negative lead-in flag: false

Question ID

QksI0uQG2YZZGrjfnglq7P

Reference Book

E6 Physiology Essentials Sembulingam 10e Part 2 p. 30-32

E6 Physiology Guyton 4SAE Part 3 p. 69-71

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