If you continued taking your birth control pill because you didn't realize you were pregnant, don't be alarmed. Despite years of this accident happening, there's very little evidence that exposure to the hormones in birth control pills causes birth defects. Still, the birth control pill is a potent estrogen.

Birth control pills aren't recommended for women over age 35 who smoke because it increases the risk of cardiovascular disease. If you're 35 or older, and you smoke, you need to quit smoking before you can safely continue using your birth control pill.

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Slight nausea, mood changes, and occasional mild weight gain are common. Consult your health care provider if these symptoms occur. Serious side effects occur infrequently, especially if you are in good health and do not smoke. If you notice severe pain in chest, head, belly, or lower leg; sudden problems with speech; dizzines; yellow skin or eyes; or breast lump, call your health care provider immediately. ^ Contraceptive FAQ | ^ Top

Traditional birth control pills make your reproductive system mimic a regular 28-day monthly cycle. For the first 21 days, you take active pills containing reproductive hormones. For the last seven days, you take a placebo. While you're taking the placebo pills, you bleed vaginally, as if you were having a regular menstrual period. By contrast, extended-cycle birth control pills contain active hormones for every day of the month.

Women often blame the birth control pill for weight gain. But studies have shown that the effect of the birth control pill on weight is small — if it exists at all. However, the way the hormones in birth control pills act on tissues in your breasts, hips and thighs can make you feel as if you've gained weight. This is usually due to fluid retention and not increased body mass or fat.

Birth control pills can affect cholesterol levels. How much of an effect depends on the type of pill you're taking and what concentration of estrogen or progestin it contains. The estrogen in birth control pills causes an increase in high-density lipoprotein (HDL) cholesterol levels (the "good" cholesterol), a decrease in low-density lipoprotein (LDL) cholesterol levels (the "bad" cholesterol) and an increase in your total cholesterol and triglyceride levels.

Birth control pills may increase blood pressure. The risk of high blood pressure in women who take birth control pills also increases with age and the duration of use. If you take birth control pills, have your blood pressure checked regularly. If you already have high blood pressure, consider an alternative form of birth control. If you do choose to take the pill, have your blood pressure closely monitored by your doctor.

The effects of antibiotics on birth control pills may be overstated — except in the case of one antibiotic, rifampin. Studies clearly show that rifampin decreases the effectiveness of birth control pills in preventing ovulation. However, rifampin isn't a widely used antibiotic. Chances are you wouldn't be taking it unless you had tuberculosis or had tested positive for the disease.

The birth control pill usually contains 2 hormones, a synthetic estrogen and synthetic progesterone. These outside hormones turn off the woman's ovaries so her ovaries do not make an egg and cause the mucus of the cervix to thicken to prevent sperm from entering the uterus.

Consult your healthcare provider. Taking pills to skip all your periods is not approved by the FDA so you will need a special prescription and instructions. You can take to your healthcare provider the handout from our website on continuous birth control pill use and ask for a prescription like this sample prescription. You will need to buy more birth control pills/packages. Normally, with a period every 21 days for you need 13 pill packages for 1 year.

It's possible to use standard estrogen-progestin birth control pills for emergency contraception, but check with your doctor for the proper dose and timing of the pills. There is a special type of contraceptive pill that's specifically designed to keep you from becoming pregnant if you've had unprotected vaginal intercourse.

Scientific evidence suggests using birth control pills for longer periods of time increases your risk of some cancers, such as cervical cancer and liver cancer, but it also decreases your risk of other types of cancer, including ovarian cancer and endometrial cancer. The effect of birth control pills on breast cancer risk isn't quite clear. However, some studies do show a link between pill use and breast cancer.

A woman still goes through menopause even if she is taking birth control pills. But she may not know it. Menopause occurs naturally when your ovaries stop making estrogen and progesterone. Eventually your menstrual periods stop, and you can no longer become pregnant. Signs and symptoms of decreased production of estrogen and progesterone include hot flashes, sleep disturbances and vaginal dryness.

To date, there is no published evidence of difficulties with birth-control pills related to PXE. [March 2006]

You can get accurate results from a pregnancy test while you're on the pill. Pregnancy tests work by measuring a specific pregnancy-related hormone — human chorionic gonadotropin (HCG) — in your blood or urine. The active ingredients in birth control pills don't affect how a pregnancy test measures the level of HCG in your system.

Ideally, under perfect circumstances the annual failure rate for the pill is .1%. However, with typical usage this failure rate increases to 3% during the first year of use. The most common reason women become pregnant on the Pill is improper usage. Pregnancies usually occur because initiation of the next cycle (the next pack of pills) is delayed or forgotten allowing for ovulation to take place. If you do become pregnant while taking the pill, immediately stop taking them.

I am 34 years old. I never used any oral contraceptive until recently. My physician gave me a prescription for Levora®. He told me to start it on Sunday, the 5th. My regular period was due on the 8th of this month. I started the medicine on the 5th, and I noticed from about the 5th until right now, that I have had slight cramping and very light spotting. I am very bloated and feel sluggish.

Yes. Birth control pills are only prescribed to prevent pregnancy; pills do not prevent sexually transmitted infections.