Fertilization of two ova released in different menstrual cycles is known as?

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

Obstetrics & Gynaecology

Easy

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

Explanation

Superfetation is the correct term for the fertilization of an ovum when a fetus is already present in the uterus from a previous cycle.
This process requires ovulation to occur despite an ongoing pregnancy, which is physiologically suppressed in humans.
The key characteristic of superfetation is the presence of two fetuses with distinctly different gestational ages.
This differs from typical twinning, where ova are released and fertilized within the same menstrual cycle.

Option B: Superfecundation refers to the fertilization of two or more ova released during the same menstrual cycle by sperm from separate acts of intercourse.
Option C: Fetus papyraceous is not a method of fertilization. It is a term describing the outcome of a twin pregnancy where one fetus dies in utero and becomes mummified and flattened.
Option D: This option is incorrect because a correct term, Superfetation, is available among the choices.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Anomalies of multiple pregnancies as background academic context rather than a clinical decision trigger.
Understanding these rare reproductive phenomena is important for differential diagnosis in obstetrics when ultrasound reveals two fetuses with a significant size and developmental discrepancy.
The hormonal environment of pregnancy (high levels of progesterone and hCG) normally prevents ovulation, making superfetation exceptionally rare and a subject of medical curiosity.
What if? If an ultrasound showed two fetuses with a size difference corresponding to several weeks of growth, the clinician would first rule out more common causes like intrauterine growth restriction (IUGR) in one twin or twin-to-twin transfusion syndrome before considering the rare possibility of superfetation.

How to Approach the Question

First, carefully read the question and identify the key phrase: 'different menstrual cycles'. This is the critical piece of information.
Next, analyze the provided options, which are specific medical terms related to multiple pregnancies.
Define each term in your mind or based on your knowledge. Superfetation involves fertilization 'on top of' an existing fetus. Superfecundation involves fertilization of multiple eggs from the same cycle.
Match the key phrase 'different menstrual cycles' to the correct definition. Fertilization in different cycles means one pregnancy starts after another is already established, which is the definition of superfetation.
Eliminate the other options. Superfecundation is incorrect because it occurs in the same cycle. Fetus papyraceous is a complication, not a type of fertilization.

Concept Tested & Keywords

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E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 1048-1050