For best results enter in the dates of the first day of your last three menstrual periods
For best results enter in the dates of the first day of your last three menstrual periods. If you can not remember these three dates, then enter in the first day of your last menstrual period.
The beginning of last menstrual period:
Month
Jan
Feb
Mar
Apr
May
June
July
Aug
Sept
Oct
Nov
Dec
Day
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Based on the average menstrual cycle of 28 days, your preceding menstrual period was on: (if this is incorrect, and you know the date feel free to change the date calculated below)
Menstrual period before the above:
Month
Jan
Feb
Mar
Apr
May
June
July
Aug
Sept
Oct
Nov
Dec
Day
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
For even more accurate calculation a preceding date is needed: (if this is incorrect, and you know the date feel free to change the date calculated below)
Preceding menstrual period:
(About 3 months ago)
Month
Jan
Feb
Mar
Apr
May
June
July
Aug
Sept
Oct
Nov
Dec
Day
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Your menstrual cycle is approximately:
days long
Date of next period should be:
Fertility information:
high fertility:
begin significant fertility
ovulation:
ends significant fertility
CAUTION :
This calendar cannot and should not be used to prevent pregnancy.