Understanding Your Fertility Timeline
Conception is a game of timing. Unlike men who are fertile every day, women have a brief window of about 6 days per cycle where pregnancy is possible. This calculator helps you pinpoint that window to maximize your chances.
⚠️ How We Calculate
This tool uses the Standard Days Method. It subtracts 14 days from your estimated next period start date. While statistically accurate for about 70-80% of women, stress, illness, or hormonal conditions (like PCOS) can shift ovulation.
The 3 Phases of Conception
1. The Fertile Window
Sperm are resilient survivors—they can live in the uterus for up to 5 days. The egg, however, is fragile and lives only 12-24 hours. Your "fertile window" is the 5 days leading up to ovulation plus the day of ovulation itself.
2. Ovulation
Triggered by a surge in Luteinizing Hormone (LH), the ovary releases an egg. If sperm are already waiting (from intercourse days prior), fertilization can happen immediately.
3. Implantation
A fertilized egg travels down the fallopian tube and implants into the uterine lining. This typically happens 6 to 12 days past ovulation (DPO). This is why you can't take a pregnancy test immediately after sex—the hormone hCG isn't produced until after implantation.
Myth Busting: The "Shettles Method"
You may have heard that timing sex can influence the gender of your baby (e.g., sex closer to ovulation for a boy, earlier for a girl). This is known as the Shettles Method.
The Reality: Modern studies largely debunk this. Evidence suggests that the timing of intercourse has no statistically significant impact on the sex of the baby. The odds remain roughly 50/50 regardless of timing.
When Should I See a Doctor?
If you are under 35 and have been trying to conceive for 12 months without success, it is recommended to see a fertility specialist. If you are over 35, the recommendation drops to 6 months. Once you confirm pregnancy, use our pregnancy due date calculator to estimate your delivery date.