Hormone responsible for skeletal maturation of fetus?

RUHS, Jaipur, M.Sc Nursing Entrance Exam-2019

Obstetrics & Gynaecology

Easy

Appeared in: RUHS, Jaipur, M.Sc Nursing Entrance Exam-2019

Explanation

Thyroxine is the primary hormone responsible for the maturation of the fetal skeleton.
It drives the process of ossification, where cartilage is converted into bone, and is essential for the proper development of the central nervous system.
The fetus depends on the mother's supply of thyroxine during the first trimester, after which the fetal thyroid gland begins to function.
Inadequate thyroxine levels can lead to developmental abnormalities, including stunted growth and intellectual disability (cretinism).

Option A: Progesterone's main function is to maintain the pregnancy by preparing the uterine lining and preventing uterine contractions.
Option C: Estrogen's primary role during pregnancy is proliferative, causing the enlargement of the mother's uterus, breasts, and external genitalia. While it plays a role in bone maturation at puberty, it is not the main driver of fetal skeletal development.
Option D: Testosterone is an androgen responsible for the development of male reproductive organs and secondary sexual characteristics in the male fetus.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain The role of hormones in fetal development, specifically skeletal maturation as background academic context rather than a clinical decision trigger.
A nurse must understand the importance of maternal thyroid health. A mother with hypothyroidism needs careful management during pregnancy to ensure the fetus receives adequate thyroxine for normal development.
Newborn screening for congenital hypothyroidism is a standard of care. Nurses are often involved in collecting the blood sample and educating parents about the importance of the test.
Early detection and treatment with levothyroxine (synthetic T4) can prevent the severe and permanent neurological and growth defects associated with congenital hypothyroidism.

How to Approach the Question

First, identify the core concept of the question: 'skeletal maturation of the fetus'.
Next, analyze the function of each hormone listed in the options in the context of pregnancy and fetal development.
Recall that Progesterone is the 'pro-gestation' hormone, primarily maintaining the pregnancy.
Remember that Estrogen is mainly for the growth of maternal reproductive tissues and the placenta.
Recognize that Testosterone is specific to male sexual development.
This leaves Thyroxine, which is known to be critical for metabolic processes, growth, and development, including the brain and skeleton. Link this general function to the specific context of the fetus to select the correct answer.

Concept Tested & Keywords

Concept Tested: The role of hormones in fetal development, specifically skeletal maturation.
Stem keywords: hormone, skeletal maturation, fetus
Lead-in keywords: responsible for

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