When you're trying to conceive, you have to take advantage of your most fertile period, which takes place about 3 days prior to ovulation to 1 day afterward. To time sex accurately for your best chance of conceiving, it's useful to know exactly when you ovulate so you can take advantage of that 5-day window. Fortunately, your body is full of subtle clues that will let you know when ovulation is approaching -- you just have to learn to recognize those clues.
Keep track of your basal body temperature (BBT) by taking your temperature with a basal thermometer every morning before getting out of bed. Keep a log of your BBT throughout each cycle. You'll begin to notice a pattern each month, with relatively consistent temperatures prior to ovulation and a rise afterward. Hormonal changes that take place after ovulation can cause your temperature to rise between 0.4 and 0.8 of a degree and remain elevated until menstruation. As your period begins -- or sometimes just before -- there is a drop in your BBT. If you do become pregnant during this cycle, your temperature won't likely take a plunge, but rather stay elevated after your period was expected to start and stay up throughout your entire pregnancy.
Monitor and record your cervical mucus. Following your period, you'll likely be relatively dry for a few days and then start to notice mucus that is tacky or sticky. Several days before ovulation your mucus will increase and change again, becoming clear, stretchy and slippery, with a consistency similar to egg whites. This is fertile cervical mucus because it is the easiest for sperm to travel through to the egg. Your final day of this type of cervical mucus is generally your most fertile. Once you have ovulated, the fluid will change, becoming creamier and less stretchy during the luteal phase -- the period from ovulation to menstruation.
Track the changes in the position of your cervix. Around the time of ovulation, it will be high up in the vagina, soft, wet and a little open; at other times during your cycle, it will be lower down in the vagina, firmer, drier and closed.
Continue to chart your basal body temperature, cervical mucus and cervical position for a few consecutive months to recognize a pattern that will help you predict when you will ovulate next. If you consistently ovulate on the same day of your cycle or very near the same day, it will be relatively easy to predict when you will ovulate again. If you don't ovulate on the same day of your cycle each month, you might still be able to recognize a pattern that will help you predict when you will ovulate. For example, you might notice that you ovulate after 3 days of slippery cervical mucus and your temperature dips one- or two-tenths of a degree just before the post-ovulation rise.
Use an ovulation predictor kit instead of or in conjunction with charting. There are several types of kits. A urine-based kit monitors the luteinizing hormone in your blood, which increases between two and five times approximately 1 to 2 days prior to ovulation. The other type of kit is a salivary ferning kit. As you near ovulation, your rising estrogen level causes the salivary salt content to increase; when dried, you can see crystallization in a fern-like manner under a pocket-sized microscope in the few days prior to ovulation. Other kits detect the levels of electrolytes in both cervical mucus and saliva, which fluctuate in response to hormonal changes.