Everything you need to know about birth control

1. The pill, patch or ring

What it is: When it comes to hormonal birth control, the only difference is in the delivery system: The pill is swallowed, the patch is applied to the skin, and the ring is inserted into the vagina. How it works: Prevents ovulation and thickens the cervical mucus to keep sperm out. Effectiveness: Between 92 and 99.7%. Convenience: The pill is taken daily; the patch is stuck on the buttocks, upper arms, lower abdomen or upper body once a week; and the ring is inserted for three weeks. Best for: Non-smoking women under age 35, within certain health parameters. Side effects: Irregular bleeding, breast tenderness, headaches and nausea for a few months in some women. Price tag: About $30 a month. Good to know: It can take six months for you to begin ovulating and regain fertility once you’ve stopped using the pill, patch or ring.

More on the pill Celebrating 51 years combating conception, the pill is one of the world’s most prescribed medications. “The pill has come a long way,” says Dara Maker, a family physician at Women’s College Hospital in Toronto. “The hormone dose has decreased by almost 50 percent, so there are fewer side effects.” Most women still worry about weight gain and mood swings, but you shouldn’t feel any different on the pill than you did off it, she says. Sometimes it just takes a little trial and error to find the pill that’s right for you. Plus, the pill comes with extra perks. For one thing, you can manipulate your periods if you don’t like menstruating every month, says Roey Malleson, a clinical associate professor of family practice at the University of British Columbia. And the pill can help clear up acne, lighten your periods and protect you from cancer. “One year on the pill gives you 15 years worth of protection from endometrial and cervical cancers, reducing your risk by 50 percent, and decreases your risk of ovarian cancer by 80 percent,” she says. “It actually protects your fertility by reducing the risk of serious infections.” On the downside, the pill does increase your risk of blood clots and shouldn’t be taken by women who have had a stroke, estrogen-dependent cancer (breast or ovarian), active liver disease, high blood pressure, or who are over 35 and smoke.

2. Injection

What it is: A shot of progesterone. How it works: Prevents ovulation and thins the lining of the uterus. Effectiveness: About 99.7%. Convenience: You need to see your doctor every three months for the injection. Best for: Women who can’t have estrogen, including nursing mothers. Side effects: Irregular bleeding and weight gain of up to five pounds. About 50% of women stop having periods. It can take up to a year to become fertile again. Price tag: May be covered by private insurance. Good to know: Progesterone can lead to bone density loss, which improves when the injections are stopped.

3. Diaphram

What it is: A latex cap that covers the cervix, blocking sperm. How it works: Filled with spermicide and inserted into the vagina before sex. Effectiveness: Between 84 and 94%. Convenience: Can be inserted several hours before sex. Best for: Women who don’t want hormones, yet want a barrier method they control. Side effects: Increased risk of urinary tract infections. Price tag: Diaphragms need to be fitted by a health care professional and require a prescription. The average cost is about $40. Good to know: The diaphragm should be used with a gel spermicide.

4. Sponge

What it is: A disposable foam sponge containing spermicide. How it works: Absorbs and kills sperm. Effectiveness: Between 84 and 91% if you haven’t given birth, and between 68 and 80% if you have. It should be used with another form of contraception. Convenience: Can be inserted several hours before sex. Best for: Women who want backup for a condom. Side effects: May increase the risk of vaginal infection. Price tag: About $5. Good to know: The sponge is effective for 12 hours, so can be left in place if you’re planning a lengthy tryst.

5. Condom

What it is: You know, that latex sheath...? How it works: Provides a physical barrier to keep the vagina sperm-free. Effectiveness: Between 85 and 98%. Convenience: May reduce spontaneity if you have to go digging for one. Best for: Couples who are spacing their kids, since condoms don’t affect fertility. Side effects: Decreased sensitivity in some men. Also, latex allergies can be an issue (look for polyurethane or silicone-coated condoms). Price tag: Available at pharmacies and grocery and convenience stores for about $10 a dozen. Good to know: Condoms are the only birth control that provide protection from sexually transmitted infections (STIs), but may not protect you from the human papilloma virus (HPV).

6. Spermicide

What it is: A sperm-killing chemical in a cream, gel, foam or suppository. How it works: Destroys sperm on contact. Effectiveness: Used alone, it’s between 71 to 82%. Convenience: A bit of a mood killer — it needs to be inserted right before sex (it’s effective for about an hour) and can be messy. Best for: Women who are using a barrier method (such as a diaphragm) who want some extra peace of mind. Side effects: May irritate both partners’ genitals. Price tag: About $15 a tube. Good to know: Spermicide offers protection from bacterial infections and pelvic inflammatory disease, and can be used as emergency backup (for instance, in case of a condom mishap, spermicide can kill any escaped sperm on contact).

7. Intrauterine Device (IUD)

What it is: There are two: the Mirena, a small T-shaped IUD, and the copper wire IUD. How it works: The Mirena releases a hormone that thins the lining of the uterus and thickens cervical mucus, while the copper IUD makes the uterus inhospitable to sperm. Effectiveness: The Mirena is 99.9%; the copper wire is 99.2%. Convenience: Once it’s inserted, you don’t have to think about birth control for at least five years. Best for: Women who cannot take estrogen and want a “semi-permanent” form of contraception. Side effects: The copper IUD can cause heavier, more painful periods. Price tag: The copper IUD is about $100, and the Mirena is about $350. Good to know: A common misconception is that an IUD can “disappear” in your body but, if inserted properly, it stays put until removed by your doctor.

8. Withdrawal

What it is: Your partner pulls out during intercourse before ejaculation. How it works: Technically, it doesn’t. Your partner’s timing may be impeccable, but that doesn’t protect you from pre-ejaculate, which contains sperm. Effectiveness: About 30% (but see above). Convenience: Convenient in the heat of the moment; could be inconvenient nine months later. Best for: Women who are comfortable with the fact they could get pregnant. Side effects: Pregnancy. Price tag: Initially, cost-free. Good to know: If using withdrawal, you should take folic acid because there is a good chance you will get pregnant.

9. Natural birth control

What it is: Natural birth control methods (such as the Fertility Awareness Method, or FAM) require that you recognize the fertile phase of your menstrual cycle. How it works: Women monitor basal body temperature and changes to cervical mucus and/or track their monthly cycles on a calendar. Effectiveness: Typically 70 to 80%. Convenience: It’s a lot of work and you need regular cycles for it to be dependable. Best for: Women who wouldn’t be devastated by a positive pregnancy test. Side effects: Pregnancy. Price tag: Anywhere from about $50 for an ovulation predictor to $500 for a fancy fertility monitor. Good to know: The more methods you use to track your fertility, the more effective it can be.

10. Vasectomy

What it is: An out-patient procedure performed under local anaesthetic. How it works: A man’s sperm ducts are blocked so sperm can’t enter the ejaculate. Effectiveness: Average failure rate is three in 1,000. Convenience: You need a backup method of birth control until after a sperm test at the three-month mark gives you the green light. Best for: Men who have all the children they want. Side effects: The no-scalpel procedure reduces the risk of complications by 80%, although there may be some swelling. Price tag: A referral to a urologist. Good to know: Reversal is possible, but there’s no guarantee — you should consider vasectomy permanent.

Vasectomy: take two “It’s kind of a funny story,” says Ryan Blackwell,* a two-time vasectomy survivor. Funny because his wife, Emily, didn’t get pregnant. But three years after his first vasectomy, she suddenly got the feeling she might be. “She said, ‘You need to get tested again. I don’t know why, but you do,’” says Blackwell. His family doctor told him he had nothing to worry about — but, just in case, sent his sperm sample to a urologist. It turned out his first vasectomy had failed. Within days, he was booking his second. “Vasectomy has the lowest failure rate of any form of contraception,” says Ronald Weiss, an assistant professor of medicine at the University of Ottawa. Most failures occur in the first 12 weeks, when any lingering sperm may still be alive. “It can fail afterward, but it’s very rare,” he says. “The body has a remarkable ability to heal itself and, in some cases, the tubes will ‘rejoin.’” If you’re worried, a simple sperm test should ease your mind. “I now have a standing arrange-ment with my family doctor to have the test done on an annual basis,” says Blackwell. “Just in case.” *Name changed by request.

11. Tubal ligation

What it is: The fallopian tubes are surgically disconnected. How it works: The egg never meets the sperm. Effectiveness: There is up to a 2.5% chance of failure up to 10 years later as tubes may “heal” themselves. Convenience: Once the procedure is over, technically so are your birth control concerns. Best for: Women who don’t want any more children. Side effects: Pain, bleeding and nausea, as well as some risk of infection. Price tag: As surgical procedures, tubal ligations are covered. Good to know: Ectopic pregnancy (pregnancy outside the uterus) is more likely in women with tubal ligation.

When “Plan A” fails …there’s always Plan B. Available over-the-counter, it’s Canada’s only approved emergency contraceptive. Plan B is a progestin pill that inhibits ovulation and implantation up to five days after unprotected sex. “I often recommend keeping a package at home because there is a chance of failure with condoms,” says Dara Maker, a family physician at Women’s College Hospital in Toronto. “But if you find you’re taking it a lot, talk to your doctor about an alternative form of birth control that might work better for you.”

We asked: What kind of birth control do you use? Here’s how you answered: The pill: 173 votes Condoms: 126 votes IUD: 90 votes Vasectomy: 67 votes Rhythm: 65 votes Tubal ligation: 55 votes Depo (injections/patch): 26 votes Sponge/spermicide: 4 votes Diaphragm: 2 votes

Our experts: Dara Maker, family physician at Women’s College Hospital in Toronto Roey Malleson, clinical associate professor of family practice at University of British Columbia Ronald Weiss, assistant professor of medicine at University of Ottawa

This article was originally published on October 2011.

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