Morning sickness during early pregnancy is due to?

IGNOU PB Bsc Nsg Entrance-2017

Obstetrics and Midwifery Nursing

Easy

Appeared in: IGNOU PB Bsc Nsg Entrance-2017

Explanation

Morning sickness is primarily caused by the rapid increase in Human Chorionic Gonadotropin (hCG) levels during the first trimester.
hCG is secreted by the placenta after implantation. Its levels rise sharply, peaking around 8-9 weeks of gestation, which directly correlates with the typical onset and peak of nausea and vomiting symptoms.
After the first trimester, hCG levels decline and stabilize, which is why morning sickness usually subsides by 16-18 weeks.
Conditions with higher hCG levels, like multiple gestations or molar pregnancy, are often associated with more severe morning sickness (hyperemesis gravidarum), further strengthening the link.

Option B: Increased acidity is related to heartburn or gastroesophageal reflux, which is common in pregnancy due to progesterone relaxing the esophageal sphincter. However, it is not the primary cause of the nausea associated with morning sickness.
Option C: While progesterone levels are high in pregnancy and cause relaxation of smooth muscles (leading to delayed gastric emptying and constipation), this effect may worsen nausea but is not the initial trigger. The primary trigger is hCG.
Option D: This is an outdated theory. While emotional stress can exacerbate any physical symptom, morning sickness is now understood to be a physiological condition caused by hormonal changes, not a psychological one.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Etiology of morning sickness in early pregnancy as background academic context rather than a clinical decision trigger.
Nurses must educate pregnant clients that morning sickness is a normal, physiological part of early pregnancy, reassuring them that it is not typically harmful to the fetus.
It is crucial to differentiate between normal morning sickness and hyperemesis gravidarum, a severe form that can lead to dehydration, weight loss, and electrolyte imbalances, requiring medical intervention.
Nursing interventions focus on dietary and lifestyle modifications, such as eating small, frequent meals, avoiding trigger foods, and staying hydrated.

How to Approach the Question

Identify the core concept: The question asks for the direct cause of morning sickness in early pregnancy.
Recall the major hormonal changes that occur in the first trimester. The most dramatic and rapid change is the surge in human chorionic gonadotropin (hCG).
Evaluate each option based on physiological principles:
Increased hCG: Its timeline of rising and falling directly matches the typical course of morning sickness.
Increased acidity: This is linked to heartburn, a different symptom.
Increased progesterone: This hormone affects smooth muscle and digestion but is not the primary trigger for nausea.

Concept Tested & Keywords

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