A woman holds a pregnancy test in front of a calendar with a circled date.

Trying to Get Pregnant: How to Chart Your Cycle

Some women seem to get pregnant just by thinking about babies. Other women can take years of careful planning and predicting to finally start a family. If you are getting frustrated at being thwarted, despite your enthusiastic efforts to have a baby, charting your menstrual cycle can help you figure out what time of the month holds your best chance at implantation. Here’s a look at understanding your menstrual cycle and how to chart it.

Why Should I Chart My Cycle?

Pregnancy is most likely to occur during ovulation. Ovulation usually lasts for about 6 days, while the mature egg is in transit and taking up residence in the uterus. Although most menstrual cycles last 28 days, and ovulation begins at day 14 on average, this is not true for every woman.  If you are serious about getting pregnant, guessing is not a very efficient way of nailing down your own body’s ovulation. Keeping track of the different symptoms your body expresses and counting days from more obvious menstrual milestones (i.e. the first day of your period) can help you figure out exactly when you are at your most fertile. 

Charting Your Cycle

A variety of apps, websites, and ovulation tests can help you track your period and tell you when you are most fertile. However, they often require a membership or are costly.  So you can learn to chart your own cycle. Just remember: It can take a few months to get a good bearing of when you are ovulating.

Consider the first day of your period day 1. If your reproductive organs are completely on point, the last day (right before your period) will be day 28. But for most women this ranges from 21-40. Start keeping careful accounting of the length of your period. This is key in pinpointing ovulation. After you have enough months to get an idea of your normal period length (at least 3-4 months), it’s time for mathematics. 

Predicting Ovulation

The easiest way to get an accurate gauge of your ovulation is by creating a span of days based on your shortest and longest cycles. The first day you may be ovulating and fertile is the shortest cycle length minus 18 days. The last day you may be ovulating is the longest cycle length minus 11 days. 

Say, for example, you kept track for 5 months, and your cycle lengths were 28, 30, 29, 31, and 30 days. The calculation would be: 28-18=10 and 31-11=20. So between days 10 and 20 of your cycle should be when you are ovulating, and have the best chance at pregnancy.

Other Signs to Consider

Your body will probably give a lot of other clues to follow. Because of the hormonal changes that accompany menstruation and ovulation, keeping track of certain symptoms and other factors will help clue you into when you are ovulating. Note these in your cycle calendar to track it all in one place.

Your basal body temperature may rise immediately after ovulation. However, the change can be subtle and as little as .1 degree so you may not notice it. Try recording your temperature every morning before you even get out of bed. The day your temperature increases, you may be ovulating, and it should stay that way until your period starts. After the third day of an increase, chances of fertilization decline. 

You may also notice that any vaginal discharge may become different. You can check this daily too, looking for an egg white-like substance. Elastic, sticky, whitish discharge is indicative of ovulation; discharge changes to help move sperm towards the egg.

Last Updated: June 01, 2017