Question 1

How do I calculate my next period date?

Accepted Answer

Add your average cycle length to the first day of your last period. For example, if your last period started on March 1 and your cycle is 28 days, your next period is expected around March 29. Cycle length is measured from the first day of one period to the first day of the next.

Question 2

What is a normal menstrual cycle length?

Accepted Answer

A normal cycle ranges from 21 to 35 days, with 28 days being the average. Cycle length can vary from month to month due to stress, illness, travel, diet changes, and hormonal fluctuations. Consistently irregular cycles may warrant a discussion with a healthcare provider.

Question 3

When is the fertile window?

Accepted Answer

The fertile window is the 6 days ending on ovulation day. Ovulation typically occurs about 14 days before the next period (not 14 days after the last period, unless you have a 28-day cycle). Sperm can survive 3-5 days in the reproductive tract, so intercourse in the days leading up to ovulation can result in pregnancy.

Question 4

What is the luteal phase?

Accepted Answer

The luteal phase is the second half of the menstrual cycle, from ovulation to the start of the next period. It is typically 12-14 days long and is more consistent than the follicular phase (before ovulation). Progesterone dominates this phase, preparing the uterine lining for potential implantation.

Cycle	Period	Fertile Window	Ovulation	Next Period
Cycle 1	Mar 21 – Mar 25	Mar 30 – Apr 5	Apr 4	Apr 18
Cycle 2	Apr 18 – Apr 22	Apr 27 – May 3	May 2	May 16
Cycle 3	May 16 – May 20	May 25 – May 31	May 30	Jun 13
Cycle 4	Jun 13 – Jun 17	Jun 22 – Jun 28	Jun 27	Jul 11
Cycle 5	Jul 11 – Jul 15	Jul 20 – Jul 26	Jul 25	Aug 8
Cycle 6	Aug 8 – Aug 12	Aug 17 – Aug 23	Aug 22	Sep 5

Menstrual Cycle Calculator

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