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Understanding Your Monthly Cycle
Understanding your menstrual cycle can help increase your chances of conceiving, if you desire to become pregnant. The menstrual cycle begins with the first day of menstrual bleeding (the menstrual period). The body releases hormones that encourage maturation of eggs inside follicles of the ovaries. From the 2nd to 14th day of the cycle, these same hormones cause the lining of the uterus to thicken and prepare for implantation of a fertilized egg. These events are referred to as the follicular stage of the menstrual cycle.
What Happens During Ovulation
Ovulation, or the release of an egg, usually occurs between the 11th and 21st day of the cycle. Ovulation is triggered by a surge in levels of the hormone luteinizing hormone (LH). The cervical mucus changes in consistency and becomes slippery, like egg whites, to facilitate the progress of sperm toward the egg. The average length of the menstrual cycle is 28 to 32 days.
It's All About Timing
At birth, females have about 1 to 2 million eggs. Over a woman’s lifetime, only 300 to 400 of them will be released through ovulation. Typically, one egg is released with every menstrual cycle. After release, the egg travels into the Fallopian tube and toward the uterus. Eggs can live about 12 to 24 hours after release, and sperm can live for 3 to 5 days. Knowing when you are due to ovulate can therefore help you plan sex with your partner for the times when you are most likely to conceive.
Tracking When You’re Most Fertile
Chances for pregnancy are usually best when sexual intercourse occurs 1 to 2 days before you ovulate. You can try to predict this time by counting backwards for 14 days from when you expect your next period, if you have a regular 28 day cycle. You should try to have sex every other day (such as on days 12 and 14) around the time you expect to ovulate. Having sex daily can reduce a man’s sperm count. If your cycle is longer or shorter, you can use an online ovulation calculator to help predict your day of ovulation.
Tracking Ovulation by Temperature
After ovulation, the empty follicle (called the corpus luteum) produces the hormone progesterone to help prepare the lining of the uterus for pregnancy. The release of progesterone causes an increase in the body temperature. Checking your basal body temperature every morning before getting out of bed is one way to try to determine when ovulation occurs. The thermometer used for this test costs about $10 at drugstores, so the test is inexpensive. However, it’s not as accurate as other ovulation tests.
Predicting Ovulation by Hormone
Home ovulation kits (ranging from $20 to $50) measure the hormone LH in the urine. The surge in LH is the trigger of ovulation, so this measurement can help identify the day of ovulation. Some kits allow for daily testing, and they are about 99% accurate.
The Last Phase of Your Monthly Cycle
Progesterone released in the second half of the menstrual cycle prepares the uterine lining for pregnancy. If this does not occur, the egg disintegrates and progesterone levels fall. About 12 to 16 days later, tissues from the lining of the uterus are expelled as menstrual bleeding. This usually takes 3 to 7 days, and then the cycle begins again.
How to Boost Ovulation
Increasing research suggests that environmental influences may decrease fertility. Leading a healthy lifestyle may improve your chances of getting pregnant. This includes eating folic acid-rich foods, avoiding alcohol and caffeine, maintaining a healthy weight, consuming more organic fruits and vegetables, and avoiding certain plastics (including plastic wrap).
Weight Does Affect Fertility
Women whose body mass index (BMI) was above normal took twice as long to conceive as those with a normal BMI in one study. Weight loss for those who are overweight can improve both fertility and pregnancy outcomes. Even a 5% to 10% weight loss can improve ovulation and pregnancy rates. Obesity in men can also cause low testosterone levels, which can be a cause of infertility.
Age Affects Conception Success
A woman's age also affects her chances of getting pregnant. For example, a healthy 30 year old woman has about a 20% chance of getting pregnant each month. This chance drops to 5% for a healthy 40 year old women. According to experts, a woman under age 35 who has been trying to conceive unsuccessfully for a year should discuss the condition with her doctor. A woman over 35 years of age should seek medical advice after 6 months of trying to conceive.
Fertility Declines in Older Men, Too
In contrast to women, there is no maximum age at which a man is unable to father a child. However, a man’s sperm count and motility of sperm both decrease with age. Men over age 45 have been shown to take longer to achieve a pregnancy when trying to conceive. You may wish to discuss with your doctor ways to enhance your chances for conception if your partner is older.
How Men Can Boost Fertility
Some lifestyle modifications may be able to boost male fertility, like maintaining a healthy weight, managing stress, and avoiding tobacco and alcohol use. Eating a diet high in zinc (meats, whole grains, eggs, and seafood), vitamin E, and selenium (meats, seafood, mushrooms, Brazil nuts, and cereals) may also help. Keeping the testicles cool can improve male fertility; hot tubs, hot baths, and saunas can all reduce sperm count.
A thorough evaluation is the first step in managing infertility, since there are so many potential causes. Treatments can include fertility drugs to stimulate ovulation and assisted reproductive technologies like in vitro fertilization (IVF). IVF involves removal of eggs from the ovaries, fertilizing them with partner sperm, and then inserting them back into the woman’s uterus.
How Home Pregnancy Tests Work
Home urine pregnancy tests can often tell if you're pregnant as early as five days before your expected period. These are based on detecting the “pregnancy hormone” or human chorionic gonadotropin (hCG) that is produced after implantation of a fertilized egg. If you test too early, you may get a false negative result, so you should repeat the test if you suspect you are pregnant. A blood test at the doctor's office can provide even more accurate results.
Five Early Signs of Pregnancy
Five early signs of pregnancy include:
- a missed menstrual period,
- feeling easily tired,
- feeling nauseous in the morning or at other times,
- needing to urinate frequently, and
- tenderness and enlargement of the breasts.
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