How to track your period: work out your cycle length step by step

You don't need any special knowledge to track your period; a calendar and a few seconds each month are enough. The real question is what to count and where to start. In this article you'll find how to identify day 1 of your cycle, how to work out your cycle and period length step by step, and when it's worth talking to your doctor about your records.

Which day is day 1 of your cycle?

Every calculation in a period calendar starts from one day: day 1 of your cycle. This is the first day of period bleeding. The last day of your cycle is the day before your next period starts.

Sometimes there's a day or two of light spotting before the actual bleeding. If you can't decide how to count those days, write the spotting down as a separate note and mark the day bleeding starts as day 1. What matters is using the same rule every month, so your months stay comparable. You can always talk through anything you're unsure about with your doctor.

How do you work out cycle length, step by step?

Cycle length is the number of days from the first day of one period to the first day of the next. Period length is how many days the bleeding lasts. The two tell you different things, so tracking them separately on your calendar makes life easier.

1. Mark the first day. On the day your period starts, put a clear mark on that day in your calendar.
2. Mark the bleeding days. Use the same mark for each day your period lasts; when it ends, you can count your period length.
3. Wait for the next first day. When your next period starts, mark that day as day 1 too.
4. Count the days in between. Counting from the first day up to the day before your new period gives you your cycle length. For example, if your period started on 3 October and the next one on 31 October, your cycle lasted 28 days.
5. Write the result down. Note each cycle length in the margin of your calendar or in a notebook; after a few months it's easy to see them side by side.

To count period length, count every day from the day bleeding starts to the day it stops. For example, a period that starts on 3 October and ends on 7 October lasted 5 days.

When counting your cycle, you include the first day but not the first day of the new period; that day is day 1 of the next cycle. This small detail prevents one-day mix-ups between months.

One month isn't enough: how many months should you track?

A single cycle tells you very little about your pattern. Cycles can vary by a few days from month to month, and stress, travel, illness or changes in your sleep can play a part. That's why putting several months of records side by side gives a much more meaningful picture than looking at a single month.

According to the NHS, the UK's national health service, the gap between periods is around 28 days on average, but it's common for it to range from 21 to 35 days. A period usually lasts between 2 and 7 days. The NHS also notes that cycles can be less regular in the first years after periods start and when you're approaching menopause, and hormonal contraception can affect your pattern too. These ranges are general information; the person who can assess your own pattern is your doctor.

When you look at a few months of records, you can ask yourself:

• How much does my cycle length change from month to month?
• How many days does my period usually last?
• Has anything changed from my usual pattern over the last few months?

The point of these questions isn't to diagnose yourself; it's to have concrete dates in hand when you talk to your doctor. If you notice a change in your pattern, we've gathered what to bring to the appointment in period changes: what to tell your doctor. If you're just getting started, Starting cycle tracking: a simple plan for your first 3 months walks you through the first three months step by step.

Practical ways to keep your calendar consistent

Paper calendar, planner or app: which one you choose matters less than using it consistently. A few small habits make it easier:

• Pick one place. If your records are spread across several notebooks and apps, counting gets harder.
• Always use the same mark. One symbol for the first day and another for bleeding days is plenty.
• Running late? Fill it in afterwards. If you remember a day or two later, still add the date; if you're not sure, note "approximate" next to it.
• Add short notes. Observations like pain, mood or a busy week come in handy later; we've collected ideas in what to note when tracking your period.

When should you talk to your doctor?

A cycle that varies a little from month to month often isn't a sign of a problem. Still, if you notice any of the following in your records, it's a good idea to talk to your doctor:

• The gap between periods is shorter than 21 days or longer than 35 days
• Your period lasts longer than 7 days
• You bleed between periods
• Your usual pattern has clearly changed
• Your periods are irregular and you're finding it hard to get pregnant

In that conversation, your records are a much firmer starting point than memory. Still, a number on a calendar doesn't mean anything on its own; you assess it together with your doctor. If you have sudden, severe symptoms such as very heavy bleeding, dizziness or unbearable pain, don't wait: call the emergency number in your country.

Tracking your period in Oveluni

In Oveluni, the Cycle area opens when you choose the women's profile; you'll find the details on the Women's profile page. When your period starts, open the Period days record from the Quick add menu and enter the start date; when it ends, you add the end date.

• Calendar: Your period days appear in their own color on the Calendar, so you can spot first days at a glance and count your cycle length easily. To read a month at a glance, have a look at our calendar view article.
• Summaries: See recorded period lengths for the time frame you choose, and use period comparison to put two equal time frames side by side.
• PDF report: Before a check-up, you can save the date range you choose as a PDF.

Oveluni doesn't calculate the date of your next period: only recorded history is shown, with no fertility, ovulation or pregnancy predictions. Oveluni is coming soon to the App Store.

Sources

1. NHS: Periods
2. NHS: Irregular periods
3. MedlinePlus: Menstruation (US National Library of Medicine)