Using Nägele's rule, if the first day of the last menstrual period is February 9, 2018, what is the estimated date of delivery?

To calculate the estimated date of delivery using Nägele's rule, you start with the first day of the last menstrual period (LMP). In this case, the LMP is February 9, 2018.

The rule generally states that you should add one year, subtract three months, and add seven days to the date of the first day of the last menstrual period.

1. Start with February 9, 2018.

2. Add one year: February 9, 2019.

3. Subtract three months: November 9, 2018.

4. Add seven days: November 16, 2018.

Therefore, the estimated date of delivery is November 16, 2018.

Each step adds precision to reach the due date based on the standard gestational period of approximately 40 weeks. This method is widely accepted in obstetrical practice for estimating due dates, providing a systematic approach to determine a woman's expected delivery date.