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NFP Physician

Guiding your health and fertility journey

Education on Natural Family Planning, cycle health, and fertility from a board-certified, NaProTechnology-trained family medicine physician.

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The Basics

When Can a Woman Get Pregnant?: Using NFP to Track Your Fertile Window

Dr. Rachel Regan, MD·January 5, 2024·1 min read
When Can a Woman Get Pregnant?: Using NFP to Track Your Fertile Window

Myths and Facts …

MYTH: Women can get pregnant any day of their cycle.

FACT: Pregnancy is only possible during the fertile window around ovulation.

What is the Fertile Window?

The fertile window refers to the period in the menstrual cycle when a woman is most likely to get pregnant. It is determined by the lifespan of both the sperm and the egg once ovulation occurs.

Duration of the Fertile Window

Typical Length: The fertile window lasts about 6 days. This includes the 5 days leading up to ovulation and the day of ovulation itself.

Sperm Lifespan: Sperm can survive in the female reproductive tract for up to 5 days.

Egg Lifespan: Once released during ovulation, the egg can be fertilized for up to 24 hours.

Additionally the probability of getting pregnant from unprotected sex for each day within the fertile window is as follows:

Conclusion

Overall, there are only a total of 6 days within a woman’s cycle in which she can conceive. However, of these 6 days, she is more likely to get pregnant on some than others. The days she has the highest chance of conceiving are the two days prior to ovulation.  Therefore, it is not only important for a couple to identify the day of ovulation, but also to be able to identify signs and symptoms of high fertility, which indicate a woman is within her fertile window.

References:

https://www.fertstert.org/action/showPdf?pii=S0015-0282%2819%2930432-7

https://my.clevelandclinic.org/health/articles/23439-ovulation

The BasicsPregnancy & PostpartumFertility

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Dr. Rachel Regan

About the author

Dr. Rachel Regan, MD

My name is Dr. Rachel Regan. I am a board-certified family medicine physician with training in full spectrum family medicine. This means that I have experience in treating all ages (newborns to geriatrics) as well as obstetrics and gynecology. However, as a Catholic physician, I have a special interest in NFP (Natural Family Planning) and using it to help diagnose and treat different women’s health issues such as irregular cycles, PMS, and infertility.

  • Doctor of Medicine
  • Board-Certified in Family Medicine
  • Full-Spectrum Family Medicine Training
  • NaProTechnology Trained Physician
Read more about Dr. Regan →

This post may include affiliate links. If you click one of them, I may receive a small commission at no extra cost to you. Thank you for your support!

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More on Cycle Health

  • Alternative Options for Dysmenorrhea: Effective Relief Without Hormonal Birth Control
  • Tail-End Brown Bleeding and Premenstrual Spotting as Indicators of Reproductive Health Issues
  • Alternative Treatments for Heavy Periods Other Than Birth Control
Dr. Rachel Regan, MD

Board-Certified Family Medicine Physician · NaProTechnology-trained

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My mission is to educate and empower couples to make informed decisions about their reproductive health using methods that are both natural and consistent with their moral values.

— Dr. Rachel Regan, MD

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