Fertility Window Estimator: Pinpoint Your Best Days to Conceive
Maximize your chances of conception by understanding your most fertile days. Our Fertility Window Estimator uses your Last Menstrual Period (LMP) and cycle length to estimate your ovulation and identify your key fertile window.
Estimate Your Fertile Window
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Understanding Your Fertile Window
Your fertile window is the most crucial time in your menstrual cycle for conception. It's a period of about 6 days: the 5 days leading up to ovulation and the day of ovulation itself. Here's why:
- Sperm Survival: Sperm can survive in the female reproductive tract for up to 5-6 days under optimal conditions.
- Egg Viability: An egg is viable for fertilization for only about 12-24 hours after it's released from the ovary (ovulation).
Therefore, having intercourse during the days leading up to and including ovulation increases the likelihood of sperm being present to fertilize the egg when it's released.
Our calculator estimates this window by first predicting your ovulation day based on your LMP and average cycle length, assuming a luteal phase (the time from ovulation to your next period) of around 14 days.
Frequently Asked Questions
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Use our Fertility Window Estimator to gain insights into your cycle or explore other helpful time and date tools.
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