Trying to conceive

Ovulation calculator: Here's how to predict if you're ovulating

What happens when you ovulate and what are your most fertile days? An ovulation calculator can help you predict the best days to conceive.

By Today's Parent
Ovulation calculator: Here's how to predict if you're ovulating

Photo: iStockphoto

Wondering how to determine your most fertile days and increase your chances of conceiving? An ovulation calculator can help keep you on the right track.

What exactly is ovulation?

Each month, one of your ovaries will release a mature egg, which will then travel down one of your fallopian tubes. The lining of your uterus thickens in case the egg is fertilized. If it is fertilized, it travels down to the uterus and settles in the rich lining. The egg only survives for about 12 to 24 hours. If it isn’t fertilized, you shed that uterine lining (that is, you get your period).

What are my most fertile days?

Most women are most fertile in the five days before ovulation and on ovulation day itself. While cycle lengths can vary, ovulation generally occurs 14 days prior to the onset of your next period. It’s hard to pinpoint exactly when the egg will be released, but because sperm can stick around for up to seven days after you have sex, your best bet for conceiving is to have regular sex from Day 11 to Day 16 (count the first day of your period as Day 1).

How can you tell if you are ovulating?

Some women claim they can feel it (like a backache or cramps on one side of the body). If you have really regular periods, you will be ovulating around the same time each month (give or take a day or two). But if you’ve just stopped oral contraceptives, if can take a few months to figure out your cycle. Some women rely on ovulation predictor kits (you can find them at the drugstore, near the pregnancy tests), look for changes in cervical mucus (it changes from dry to wetter and clearer when you’re about to ovulate) or chart their basal body temperature (BBT), which means taking their temperature orally when their bodies are at rest. Using a basal body thermometer (they’re more sensitive than regular ones), take a reading at the same time every morning before you get out of bed. A temperature that is slightly higher (anywhere from half a degree to eight-tenths of a degree) indicates that you likely ovulated within the past 12 to 24 hours. After a few months of charting, you’ll get to know your body’s patterns better and be able to predict your most fertile windows—and the best days to have sex—with greater accuracy. There are also free online graphs and apps you can use to chart your temperature over time. Fun fact: Once you conceive, your body temperature remains elevated throughout the pregnancy.

This article was originally published on Mar 20, 2017

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