In the antenatal OPD, a woman reports that July 10, 2019 is the first day of her Last Menstrual Period (LMP). What would be the Expected Date of Delivery (EDD) according to Naegele's Rule?

1. A

   May 10, 2020

2. B

   April 10, 2020

3. C

   May 17, 2020

4. D

   April 17, 2020

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2019

Explanation

• Naegele's rule is a standard formula used to predict the due date for a pregnancy.
• The rule estimates the expected date of delivery (EDD) by adding one year, subtracting three months, and adding seven days to the first day of a woman's last menstrual period (LMP).
• Alternatively, one can add 9 months and 7 days to the LMP.
• Starting with the LMP of July 10, 2019:.
• Add 7 days: July 17, 2019.
• Subtract 3 months: April 17, 2019.

Why Other Options Were Wrong

• Option A: This option incorrectly calculates the month. It appears to have added 10 months to the LMP date, which is not part of Naegele's rule.
• Option B: This option correctly subtracts three months from July to get April but fails to add the required seven days to the date.
• Option C: This option correctly adds seven days to the date but makes an error in the month calculation, resulting in May instead of April.

Related Visual

Clinical Relevance

• Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Calculating Expected Date of Delivery (EDD) using Naegele's Rule as background academic context rather than a clinical decision trigger.
• Calculating the EDD is a fundamental skill in antenatal care. It helps in scheduling prenatal visits, timing of specific tests (like aneuploidy screening), and planning for delivery.
• Naegele's rule is based on the assumption of a regular 28-day menstrual cycle with ovulation occurring on day 14. It is less accurate for women with irregular cycles.
• For women with irregular cycles or uncertain LMP, a first-trimester ultrasound measuring the crown-rump length (CRL) is the most accurate method for determining the gestational age and EDD.

How to Approach the Question

• Identify the key information provided in the question: the first day of the Last Menstrual Period (LMP) is July 10, 2019.
• Recall the formula for Naegele's Rule: EDD = LMP + 7 days - 3 months + 1 year.
• Apply the formula step-by-step to the given LMP.
• Step 1: Start with the date: July 10, 2019.
• Step 2: Add 7 days to the date: 10 + 7 = 17. The date is now July 17, 2019.
• Step 3: Subtract 3 months from the month: July (7th month) - 3 months = April (4th month). The date is now April 17, 2019.

Concept Tested & Keywords

• Concept Tested: Calculating Expected Date of Delivery (EDD) using Naegele's Rule
• Stem keywords: Last Menstrual Period (LMP), Expected Date of Delivery (EDD), Naegele's Rule
• Lead-in keywords: What would be
• Clinical cues: LMP: July 10, 2019

Question ID

QYj8uKp1aVW_dgEJUeYFfP

Copy ID

Reference Book

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