| What is menstruation? | Menstruation - having periods - is part of the female reproductive cycle that starts when girls become sexually mature at the time of puberty. During a menstrual period, a woman bleeds from her uterus (womb) via the vagina. This lasts anything from three to seven days. Each period commences approximately every 28 days if the woman does not become pregnant during a given cycle. |
| What is the luteal phase? | The luteal phase, also referred to as 'days past ovulation' or 'DPO', is the part of the cycle that starts at ovulation and ends the day before your next period. It usually lasts about 14 days and does not vary by more than a day in each person. The luteal phase is named after the corpus luteum (Latin: "yellow body"), a structure that grows on the surface of the ovary where a mature egg was released at ovulation. The corpus luteum produces progesterone in preparing the body for pregnancy. Your luteal phase must be at least 10 days long to support pregnancy. |
| How long is my luteal phase? | The only way to determine the exact length of your luteal phase is through hormone-specific blood tests. |
| What if I don't know how long my luteal phase is? | If you are not sure about the length of your luteal phase, you can assume it is 14 days (the average length for most women). |
Please don't take this calculator as absolute truth. Be aware that this is just an estimate based on facts you have input matched up with standard mathematical computations. Please also be aware that only 6% of pregnancies happen on the actual due date estimated. If you are pregnant or think you are, visit a doctor and get the FACTS.