Skip to content
Calcapedia
Print as
Number of problems

In the print window, choose “Save as PDF” as the printer (or print it on paper). Seed 1 rebuilds this exact sheet.

Showing 10 problems, seed 1.

Implantation Date worksheet

Grades 3–4

Solve each problem and show your work. Round answers to 2 decimal places where needed.

  1. Problem 1.
    • I know: The first day of my last period
    • First day of last period: Nov 22, 2024
    • Average cycle length: 38 days

    Find: Most likely implantation days

  2. Problem 2.
    • I know: The first day of my last period
    • First day of last period: Jun 20, 2026
    • Average cycle length: 32 days

    Find: Most likely implantation days

  3. Problem 3.
    • I know: My ovulation date
    • Ovulation date: Oct 23, 2025

    Find: Most likely implantation days

  4. Problem 4.
    • I know: My ovulation date
    • Ovulation date: Apr 7, 2025

    Find: Most likely implantation days

  5. Problem 5.
    • I know: My ovulation date
    • Ovulation date: Jan 27, 2025

    Find: Most likely implantation days

  6. Problem 6.
    • I know: My ovulation date
    • Ovulation date: Aug 10, 2026

    Find: Most likely implantation days

  7. Problem 7.
    • I know: My ovulation date
    • Ovulation date: May 6, 2025

    Find: Most likely implantation days

  8. Problem 8.
    • I know: My ovulation date
    • Ovulation date: Nov 11, 2025

    Find: Most likely implantation days

  9. Problem 9.
    • I know: The first day of my last period
    • First day of last period: Aug 21, 2026
    • Average cycle length: 24 days

    Find: Most likely implantation days

  10. Problem 10.
    • I know: The first day of my last period
    • First day of last period: Apr 23, 2025
    • Average cycle length: 32 days

    Find: Most likely implantation days

Answer key: Implantation Date worksheet

  1. 1. Most likely implantation days: Dec 24, 2024 – Dec 26, 2024

    1. Ovulation is estimated 14 days before the next period, so subtract 14 from the cycle length

      38−14=24 days
    2. Add that to the first day of the last period to estimate ovulation

      Nov 22, 2024 + 24 days=Dec 16, 2024
    3. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Dec 16, 2024 + 8 to 10 days=Dec 24, 2024 – Dec 26, 2024
    4. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Dec 16, 2024 + 6 to 12 days=Dec 22, 2024 – Dec 28, 2024
    5. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Dec 16, 2024 + 14 days=Monday, Dec 30, 2024
  2. 2. Most likely implantation days: Jul 16, 2026 – Jul 18, 2026

    1. Ovulation is estimated 14 days before the next period, so subtract 14 from the cycle length

      32−14=18 days
    2. Add that to the first day of the last period to estimate ovulation

      Jun 20, 2026 + 18 days=Jul 8, 2026
    3. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Jul 8, 2026 + 8 to 10 days=Jul 16, 2026 – Jul 18, 2026
    4. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Jul 8, 2026 + 6 to 12 days=Jul 14, 2026 – Jul 20, 2026
    5. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Jul 8, 2026 + 14 days=Wednesday, Jul 22, 2026
  3. 3. Most likely implantation days: Oct 31, 2025 – Nov 2, 2025

    1. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Oct 23, 2025 + 8 to 10 days=Oct 31, 2025 – Nov 2, 2025
    2. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Oct 23, 2025 + 6 to 12 days=Oct 29, 2025 – Nov 4, 2025
    3. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Oct 23, 2025 + 14 days=Thursday, Nov 6, 2025
  4. 4. Most likely implantation days: Apr 15, 2025 – Apr 17, 2025

    1. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Apr 7, 2025 + 8 to 10 days=Apr 15, 2025 – Apr 17, 2025
    2. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Apr 7, 2025 + 6 to 12 days=Apr 13, 2025 – Apr 19, 2025
    3. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Apr 7, 2025 + 14 days=Monday, Apr 21, 2025
  5. 5. Most likely implantation days: Feb 4, 2025 – Feb 6, 2025

    1. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Jan 27, 2025 + 8 to 10 days=Feb 4, 2025 – Feb 6, 2025
    2. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Jan 27, 2025 + 6 to 12 days=Feb 2, 2025 – Feb 8, 2025
    3. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Jan 27, 2025 + 14 days=Monday, Feb 10, 2025
  6. 6. Most likely implantation days: Aug 18, 2026 – Aug 20, 2026

    1. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Aug 10, 2026 + 8 to 10 days=Aug 18, 2026 – Aug 20, 2026
    2. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Aug 10, 2026 + 6 to 12 days=Aug 16, 2026 – Aug 22, 2026
    3. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Aug 10, 2026 + 14 days=Monday, Aug 24, 2026
  7. 7. Most likely implantation days: May 14, 2025 – May 16, 2025

    1. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      May 6, 2025 + 8 to 10 days=May 14, 2025 – May 16, 2025
    2. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      May 6, 2025 + 6 to 12 days=May 12, 2025 – May 18, 2025
    3. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      May 6, 2025 + 14 days=Tuesday, May 20, 2025
  8. 8. Most likely implantation days: Nov 19, 2025 – Nov 21, 2025

    1. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Nov 11, 2025 + 8 to 10 days=Nov 19, 2025 – Nov 21, 2025
    2. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Nov 11, 2025 + 6 to 12 days=Nov 17, 2025 – Nov 23, 2025
    3. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Nov 11, 2025 + 14 days=Tuesday, Nov 25, 2025
  9. 9. Most likely implantation days: Sep 8, 2026 – Sep 10, 2026

    1. Ovulation is estimated 14 days before the next period, so subtract 14 from the cycle length

      24−14=10 days
    2. Add that to the first day of the last period to estimate ovulation

      Aug 21, 2026 + 10 days=Aug 31, 2026
    3. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      Aug 31, 2026 + 8 to 10 days=Sep 8, 2026 – Sep 10, 2026
    4. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      Aug 31, 2026 + 6 to 12 days=Sep 6, 2026 – Sep 12, 2026
    5. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      Aug 31, 2026 + 14 days=Monday, Sep 14, 2026
  10. 10. Most likely implantation days: May 19, 2025 – May 21, 2025

    1. Ovulation is estimated 14 days before the next period, so subtract 14 from the cycle length

      32−14=18 days
    2. Add that to the first day of the last period to estimate ovulation

      Apr 23, 2025 + 18 days=May 11, 2025
    3. In the research this uses, implantation most often happened 8 to 10 days after ovulation, so add those days

      May 11, 2025 + 8 to 10 days=May 19, 2025 – May 21, 2025
    4. It was seen as early as 6 and as late as 12 days after ovulation, which gives the wider window

      May 11, 2025 + 6 to 12 days=May 17, 2025 – May 23, 2025
    5. Your next period is due about 14 days after ovulation. That is the usual day to take a home test

      May 11, 2025 + 14 days=Sunday, May 25, 2025