Baby Girl Conception Planner (Shettles Method)
Calculate the optimal timing for conceiving a baby girl based on the Shettles Method. Visual calendar with specific fertility windows.
About
Planning for a specific gender involves understanding the biological differences between X-chromosome and Y-chromosome sperm. The Shettles Method suggests that X-chromosome sperm (female) are slower but more resilient than their male counterparts. They survive longer in the reproductive tract. To increase the probability of conceiving a girl, this planner identifies a specific window well before ovulation. The goal is to have intercourse when the environment favors the longevity of X-sperm while the faster Y-sperm die off before the egg is released. Precision is key. Users must track their cycles diligently for months to use this effectively.
Formulas
The core calculation centers on estimating the date of ovulation (O) and subtracting days to find the "Girl Window" (Wgirl).
Reference Data
| Factor | X-Sperm (Girl) | Y-Sperm (Boy) |
|---|---|---|
| Speed | Slower Swimmers | Faster Swimmers |
| Lifespan | Longer (3-5 Days) | Shorter (24 Hours) |
| Size | Larger Head | Smaller Head |
| pH Preference | Acidic Environment | Alkaline Environment |
| Timing | 2-4 Days Before Ovulation | Day of Ovulation |
| Discovery | Dr. Landrum Shettles | Dr. Landrum Shettles |
| Strategy | "Wait and Wait" | "Sprint to Finish" |
| Success Rate | ~75% (Theoretical) | ~75% (Theoretical) |