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    Health & Pregnancy

    Ovulation Calculator:

    Charting Fertility

    This calculator helps you predict your most fertile days of the month. Menstrual periods vary from woman to woman and month to month. Use this calculator to help determine the timing of your ovulation and peak fertility.

    CAUTION: This tool cannot and should not be used to prevent pregnancy.

    • Please enter a valid date (mm/dd/yyyy)

    For more accurate ovulation dates, please fill in your previous 2 menstrual periods.

    • Please enter a valid date (mm/dd/yyyy)
    • Please enter a valid date (mm/dd/yyyy)

    Your Results Edit your entry days.

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    Based on the information you've provided your cycles are about . Your most fertile days for the next three cycles are:


    Your next expected period is:

    Rollover calendar icons for more information.
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    • Take Pregnancy Test
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    • Low Fertility
    • High Fertility
    • Expected Period
    • Take Pregnancy Test

    Menstrual Cycles

    A typical 28 day cycleThe average menstrual cycle is 28 to 32 days. Some women have longer or shorter cycles, so the exact timing of ovulation can vary. Here's an overview of a typical 28-day menstrual cycle.

    Day 1

    Your cycle begins on the first day of blood flow.

    Days 2-14 Follicular Phase

    The follicles on your ovary become active, and your cervical mucus starts to thin.

    Day 14

    Ovulation occurs mid-cycle, but can vary from between Day 11 and Day 21 of a woman's cycle. Rising estrogen levels trigger the LH surge, which causes the follicle to ovulate and release an egg. It's important to chart your basal body temperature and LH surge so you know when you ovulate.

    Days 15-22 Luteal Phase

    After releasing the egg, the follicle produces progesterone, which thickens the lining of the uterus for implantation.

    Days 23 to 24

    Implantation of a fertilized egg can take place. At this point, hormones produced by pregnancy may be detected by a pregnancy test.

    Days 25 to 28

    If pregnancy does not occur, your hormone levels begin to fall. The uterine lining sheds, resulting in your period.


    Signs of Ovulation

    • A slight rise in basal body temperature, typically 1/2 to 1 degree, measured by a thermometer
    • Higher levels of LH, luteinizing hormone, measured on a home urine test
    • Cervical mucus, or vaginal discharge, may appear clearer, thinner, and stretchy
    • Tender breasts
    • Abdominal bloating
    • Light spotting
    • Slight pain or ache on one side of the abdomen

    7 Pregnancy Tips

    1. 1. Have Sex Often: Your odds of getting pregnant are best when you have sex 1 to 2 days before you ovulate. But cycles vary in length, and some women are irregular or have miscalculated their cycle. Sperm can survive in a woman's body for up to 5 days. To hedge your bet, have sex frequently starting 3 days before ovulation and continuing for 2 to 3 days after you think you've ovulated.
    2. 2. Lie Low After Sex: Give sperm a chance to swim upstream before going to the bathroom. Stay in bed for at least a few minutes after intercourse.
    3. 3. Create a Sperm-Friendly Environment: Avoid vaginal sprays, scented tampons, artificial lubricants, and douching. They can alter the normal acidity of the vagina.
    4. 4. Know When You Ovulate: Chart your basal body temperature and your cervical mucus. You might also use an over-the-counter ovulation predictor kit (OPK) to check for hormonal changes in your urine before ovulation.
    5. 5. De-Stress: Try yoga, meditation, or long walks to reduce stress. Research indicates that stress can interfere with getting pregnant. No need to quit your job or change your life. Simple acts such as exercising, writing in a journal, or holding hands with your spouse can lower stress.
    6. 6. Maintain a Healthy Weight: Studies show that weighing too little — or weighing too much — can disrupt ovulation and may also affect production of key reproductive hormones. A healthy BMI is between 18.5 and 24.9.
    7. 7. Trying for a Boy or a Girl? There's no sure, natural way to choose the sex of your baby. But male sperm swim and expire faster than female sperm. To aim for a boy, have intercourse about 12 hours before you ovulate — or as close to ovulation as possible — so the male sperm will be there when the egg drops. To aim for a girl, have intercourse several days before ovulation, so more female sperm will be around when the egg drops. Still, experts say your odds are 50-50 unless you use a sperm-sorting technique, followed by artificial insemination.

    High Fertility Days

    Ovulation and Pregnancy Tips

    First Day of Your Menstrual Cycle

    Understanding Your Menstrual Cycle

    Take a Pregnancy Test

    If your period has not started, take a pregnancy test.

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