Pregnancy can be prevented through various methods including barrier methods, hormonal birth control, intrauterine devices (IUDs), natural family planning, and permanent sterilization. The most effective ways to prevent pregnancy are consistent and correct use of contraceptives such as birth control pills, condoms, IUDs, implants, and surgical options like tubal ligation or vasectomy.

Key Methods to Prevent Pregnancy

• Barrier Methods: These prevent sperm from reaching the egg and include male and female condoms, diaphragms, cervical caps, and contraceptive sponges. Condoms uniquely also protect against sexually transmitted infections (STIs). Male condoms, when used correctly, are highly effective at preventing pregnancy.
• Hormonal Birth Control: Includes pills, injections, vaginal rings, implants, and hormonal IUDs. These methods work mainly by preventing ovulation and can be more than 99% effective with perfect use.
• Intrauterine Devices (IUDs): Small devices inserted into the uterus, either hormonal or copper-based, providing long-term contraception lasting from 5 to 10 years.
• Natural Family Planning: Tracking ovulation and fertility signs to avoid sex on fertile days. This method requires careful monitoring and is less effective compared to others.
• Emergency Contraception: Pills or copper IUDs can be used after unprotected sex to reduce the risk of pregnancy.
• Permanent Methods: Sterilization through tubal ligation for females or vasectomy for males is a permanent way to prevent pregnancy.
• Abstinence: Refraining from all sexual activity is the only 100% effective method.

Effectiveness

• Most hormonal and long-acting methods when used correctly have effectiveness rates of over 99%.
• Barrier methods like condoms are effective but depend heavily on correct use.
• Natural family planning has a lower effectiveness due to human error.
• Withdrawal method is not recommended due to low reliability.
• Lactational amenorrhea (exclusive breastfeeding) can be very effective up to six months postpartum if conditions are met.

Use of contraception should consider factors like protection against STIs, convenience, side effects, and personal health conditions. These methods help plan or prevent pregnancy effectively, but only condoms also protect against STIs.