Increasing Fertility:

Baby-making basics

Conception is based on an intricate series of events.

Every month, hormones from your pituitary gland stimulate your ovaries to release an egg, or ovulate. This often happens around day 14 of the menstrual cycle, although the exact timing may vary among women or even from month to month. Once the egg is released, it travels to the fallopian tube. If you want to conceive, now's the time. The egg has about 24 hours to unite with a sperm. Since sperm cells can survive in your reproductive tract for two to three days, it's best to have regular sex during the days leading up to ovulation.

If the egg is fertilized, it'll travel to the uterus two to four days later. There it'll attach to the uterine lining. You're pregnant! Your periods will stop as your body begins to support the embryo.

If the egg isn't fertilized, it'll break down and you'll have your next period as usual.

Understanding when you're most fertile

Learning how ovulation works is one thing. Determining when it's actually happening is something else. For many women, it's like hitting a moving target.

Keep an eye on the calendar

Use your day planner or another simple calendar to mark the day your period begins each month. Also track the number of days each period lasts. If you have a consistent 28-day cycle, ovulation is likely to begin about 14 days after the day your last period began.

If your cycles are somewhat irregular, subtract 18 from the number of days in your shortest cycle. When your next period begins, count ahead this many days. This is a reasonable guess for your most fertile days.

• Pros: Calendar calculations can be done simply on paper. And they're free!
• Cons: Many factors may affect the exact timing of ovulation, including illness, stress and exercise. Counting days is often inaccurate, especially for women who have irregular cycles.

Watch for changes in cervical mucus
Just before ovulation, you'll notice an increase in clear, slippery vaginal secretions — if you check for it. These secretions typically resemble raw egg whites. After ovulation, when the odds of becoming pregnant are slim, the discharge will become cloudy and sticky or disappear entirely.

• Pros: Changes in vaginal secretions are often an accurate sign of impending fertility. Simple observation is all that's needed, particularly inside the vagina.
• Cons: Judging the texture or appearance of vaginal secretions can be somewhat subjective.

Track your basal body temperature
This is your body's temperature when you're at rest. Ovulation may cause a gradual rise in temperature or even a sudden jump — typically between 0.5 and 1.6 degrees Fahrenheit.

You'll be most fertile during the two to three days before your temperature rises. You can assume ovulation has occurred when the slightly higher temperature remains steady for three days or more.

Use an oral thermometer to monitor your basal body temperature. Try the digital variety or one specifically designed to measure basal body temperature. Simply take your temperature every morning before you get out of bed. Plot the readings on graph paper and look for a pattern to emerge.

• Pros: It's simple. The only cost is the thermometer. It's often most helpful to determine when you've ovulated and judge if the timing is consistent from month to mon