5 Myths About Birth Control

People will do anything to avoid unintended pregnancy, from showering right after sex to using two condoms at the same time (hint: that doesn't work). There are plenty of safe and effective ways to prevent pregnancy, but according to the Centers for Disease Control and Prevention, 49 percent of all pregnancies are unplanned -- and about half of those are among women who were not using contraception at the time they became pregnant.

The CDC further reports that 62 percent of women in the U.S. at reproductive age -- between 15 and 44 -- use some form of contraception. The most popular form of birth control is the pill, followed by intrauterine devices, hormonal contraceptives such as patches, injections and vaginal rings, and condoms.

Despite how pervasive birth control is, there are lingering misconceptions about its benefits, symptoms and side effects. That's a problem because women (and their partners) need to know the facts about contraception before making the decision to use it -- and choosing the right kind -- experts say. Here are five common myths about birth control, plus the truths behind them:

Myth No. 1: The pill will make you gain weight.

Not true. "Studies have shown that women often begin using the pill during a time of life that happens to coincide with weight changes, giving the pill an unfair reputation for causing weight gain," says Dr. Dawn Stacey , a Florida-based licensed mental health counselor and former family planning specialist.

Most birth control pills contain various doses of the hormones estrogen and progestin, which can result in a number of side effects, such as mood swings, breast tenderness and nausea, but weight gain is rare, says Dr. Petra Casey, an associate professor of obstetrics and gynecology at the Mayo Clinic in Rochester, Minnesota.

If you've recently started taking the pill and think you're gaining weight, you may just be bloated. "Many women experience abdominal fluid retention during the first months of taking the pill," Casey says. "But studies have shown that the pill does not cause weight gain, extra calories do." Some birth control pills cause more fluid retention than others, so if your bloating persists, talk to your health care provider about switching to a brand that promotes fluid loss.

[See: Tampons, Pads or Menstrual Cups? A Woman's Guide to Period Products.]

Myth No. 2: Birth control is free.

Not quite. The Affordable Care Act -- passed in 2010 -- requires private insurance plans to offer their female employees birth control without copays or deductibles, according to Planned Parenthood. "Because of the Affordable Care Act, more women can have access to more effective birth control methods that may have been too expensive to use in the past," Stacey says.

While this legislation has changed the way women are charged for birth control, that doesn't mean all birth control is now free. Most generic brands of pills, patches and injections are available to women without a copay, but methods such as IUDs and rings are not covered by all insurance providers. In addition, some religious organizations are exempt from providing birth control to their employees, and women on a grandfathered plan may not be eligible to receive free birth control until they renew their plan.

The best way to find out what your plan covers is by checking with your employer or insurance agency.

Myth No. 3: All antibiotics cancel out the pill.

Most antibiotics won't affect your birth control -- the only antibiotics that can make hormonal contraceptives less effective are rifampicin and rifabutin, according to the National Institutes of Health. These drugs increase the enzymes in your body and are used to treat diseases such as tuberculosis and meningitis. The extra enzymes that these antibiotics produce can prevent the pill from being absorbed, making women vulnerable to unwanted pregnancy.

If you're taking rifampicin or rifabutin, Stacey says it's wise to use a different form of contraception, like condoms, as a precaution.

Since every woman's body responds differently to antibiotics, it's impossible to determine if other medication will make the pill less effective. Casey says it's best to inform your health care provider if you're on the pill and ask if there's a chance your antibiotics can affect your birth control.

[See: In Vitro Fertilization Grows Up.]

Myth No. 4: Your body needs a break from birth control.

While women using hormonal contraceptives such as pills and patches can choose to give their bodies a break at any time, Stacey says it's not necessary. "The pill can be taken for 15 or more years consecutively without any increased risks," she says. Stopping birth control puts sexually active women at risk for pregnancy, and it's common for introductory side effects, such as spotting and irregular periods, to occur when a woman starts taking birth control again.

Continued use of birth control actually benefits the body. "Studies show that the longer you're on birth control, the more consistent your hormone levels," Casey says. Consistent hormone levels have positive effects on your body, including lower risk of heavy bleeding, clear skin, lighter menstrual cramps and a decreased risk of uterine and ovarian cancer.

The only exception to the rule is the birth control injection -- studies show that the shot is linked to bone mineral loss, so the Food and Drug Administration recommends women stop taking it after two years of continuous use.

[See: 11 Changes Women Go Through in Menopause.]

Myth No. 5: IUDs can make you infertile.

Not true. IUDs have a bad reputation because an early version sold in the 1960s called the Dalkon Shield was linked to pelvic infections that caused infertility. Today's IUDs are designed to reduce the rate of infection, according to the Guttmacher Institute, a sexual health research organization. Not only is there no scientific evidence that IUDs can cause infertility, but they're the suggested birth control methods for women of all ages. "Long-acting reversible contraceptives, like IUDs, are now recommended by the American College of Obstetricians and Gynecologists," Casey says.

Unlike other birth control methods, IUDs carry no risk for human error. The Guttmacher Institute reports that the IUD is 99 percent effective at preventing pregnancy, while the pill has a 90 percent effectiveness rate. "IUDs offer higher safety and higher efficacy than pills, patches and other forms of contraception," Casey says.