First day of menstrual cycle is 14 August. The EDD according to Naegele's formula is?

Appeared in: AIIMS Rishikesh & Jodhpur NO - 2017

Explanation

Naegele's formula is a common method to estimate the due date.
The formula involves adding 9 months and 7 days to the first day of the Last Menstrual Period (LMP).
Given LMP is 14 August.
Calculation: 14 August + 9 months = 14 May (of the next year).
Then, 14 May + 7 days = 21 May.
Thus, the Expected Date of Delivery (EDD) is 21 May.

Option B: This date is incorrect. It may result from adding 10 months to the LMP without adding the extra 7 days.
Option C: This date is incorrect. It might be the result of adding 10 months and 7 days to the LMP, which is not the correct application of Naegele's formula.
Option D: This date is incorrect. It represents adding only 9 months to the LMP and forgetting the crucial step of adding 7 days.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Calculating the Expected Date of Delivery (EDD) using Naegele's formula as background academic context rather than a clinical decision trigger.
Estimating the EDD is a fundamental part of antenatal care. It helps in scheduling prenatal visits, timing important screening tests (like for aneuploidy or gestational diabetes), and monitoring fetal growth and well-being.
An accurate EDD is crucial for making decisions about managing post-term pregnancy and determining the timing of induction if necessary.
What if? If the woman had an irregular menstrual cycle, Naegele's rule would be less reliable. In such cases, an early first-trimester ultrasound (ideally between 7 and 12 weeks) would be the most accurate method to establish the gestational age and EDD.

How to Approach the Question

First, identify the key information provided in the question: the first day of the Last Menstrual Period (LMP) is 14 August.
Recall Naegele's formula for calculating the Expected Date of Delivery (EDD). The formula is: EDD = LMP + 9 months + 7 days.
Apply the formula step-by-step. Start with the LMP date: 14 August.
Add 9 calendar months to this date. Counting forward 9 months from August leads to May of the following year. The date becomes 14 May.
Finally, add 7 days to this new date: 14 May + 7 days = 21 May.
Compare the calculated date (21 May) with the given options to find the correct answer.

Concept Tested & Keywords

Concept Tested: Calculating the Expected Date of Delivery (EDD) using Naegele's formula.
Stem keywords: menstrual cycle, 14 August, EDD, Naegele's formula
Lead-in keywords: is?
Negative lead-in flag: false

QjqxKTwtbOVOB_-NzHG5O6

E6 Comprehensive Textbook of Community Health Nursing for BSc Nursing Students Part 2 — Subpart A (pp 1-275 of 550) p. 195-197

E6 Obstetrics Williams p. 72-94

Practise the full AIIMS Rishikesh & Jodhpur NO - 2017

Attempt every question from this paper in a timed mock, then review the full solution for each one.