关于本计算器
Fertility calendar from last period and cycle length: ovulation day, fertile window, next period — plus due date (Naegele +280 days).
排卵与怀孕计算器
按周期计算易孕期、排卵日与预产期。
排卵日
10月20日周二
易孕期10月15日周四 → 10月21日周三
下次月经11月3日周二
常见问题
When is ovulation?
Roughly cycle length minus 14 days after period start; the fertile window spans 5 days before to 1 day after.
How is the due date computed?
First day of last period plus 280 days (40 weeks).
How accurate is it?
Estimates for regular cycles; irregular cycles need a doctor’s dating.