Birth Control Barrier Methods

The practice of birth control or preventing pregnancy is as old as human existence. For centuries, humans have relied upon their imagination to avoid pregnancy.  
 

• Ancient writings dating back to 1850 BC refer to techniques using a device placed in a woman’s vagina made of crocodile dung and fermented dough, which most likely created a hostile environment for sperm. Other items placed in the vagina included plugs of gum, honey, and acacia.
  
  
• During the early second century in Rome, a highly acidic concoction of fruits, nuts, and wool was placed on the cervix as a type of spermicidal barrier.

Today’s barrier methods include the male condom, which is inexpensive, available everywhere, and effective when used properly. The female condom is used less often. Women often elect, instead, to use a diaphragm or cervical cap. Both require a doctor’s visit.

The condom (also called a rubber) is a thin sheath placed over an erect penis. A man would put a condom over his penis before he places the penis in a woman’s vagina. A condom worn by a man prevents pregnancy by acting as a barrier to the passage of semen into the vagina. A condom can be worn only once. It is one of the most popular birth control barriers. You can buy condoms at most drugstores and grocery stores and dispensers can be found in public restrooms.
 
Condoms made from latex are the best at preventing pregnancy. They also protect against sexually transmitted diseases such as AIDS and gonorrhea. Do not use condoms with Vaseline or other brands of petroleum jelly, lotions, or oils. They can decrease the effectiveness of the condom and increase the chance of pregnancy and transmission of sexually transmitted disease. Condoms can be used with lubricants that don't have oil, such as K-Y Jelly. 
  
Male condom use has increased from 13.2-18.9% among all women of reproductive age because of their concern about getting HIV (the virus that leads to AIDS) and other STDs. 
 

• How effective: The failure rate of condoms in couples that use them consistently and correctly during the first year of use is estimated to be about 3%. However, the true failure rate is estimated to be about 14% during the first year of typical use. This marked difference of failure rates reflects the error of usage. Some couples fail to use condoms every time they have sexual intercourse. Condoms may fail (break or come off) if you use the wrong type of lubricant (for example, using an oil-based lubricant with a latex condom will cause it to fall apart). The condom may not be placed properly on the penis. Also, the man may not use care when withdrawing. 
  
  
• Advantages: Condoms are readily available and usually are low cost. A prescription is not necessary. This method involves the male partner in the contraceptive choice. Besides abstinence, latex condoms are the best protection against STDs. They are the only kind of birth control that is highly effective in preventing AIDS.  
  
  
• Disadvantages: Condoms possibly decrease enjoyment of sex. Some users may have a latex allergy. Condom breakage and slippage makes them less effective. Oil-based lubricants may damage the condom.

The female condom (brand name: Reality) is a polyurethane sheath intended for 1-time use, similar to the male condom. It contains 2 flexible rings and measures 7.8 cm in diameter and 17 cm in length. You can buy them at a drugstore without a prescription. The ring at the closed end of the sheath serves as an insertion mechanism and internal anchor that is placed inside a woman’s vagina just before sex. The other ring forms the external edge of the device and remains outside of the canal after insertion.
 
The female condom prevents pregnancy by acting as a barrier to the passage of semen into the vagina. Do not have a male partner use a condom at the same time because they may stick to each other, leading to slippage or displacement of either device. If you have a choice between the two, have the male use a condom for better protection.
 

• How effective: Early tests show a pregnancy rate of 15% in 6 months. In August, 2002, the U.S. Food and Drug Administration (FDA) listed a higher failure rate of 21 pregnancies per 100 women per year. The proportion of women using this method of contraception in the United States is less than 1%. 
  
  
• Advantages: The female condom provides some protection to the labia and the base of the penis during intercourse. Although it may provide some protection, it is not as effective as a latex male condom in preventing STDs. The sheath is coated on the inside with a silicone-based lubricant. It does not deteriorate with oil-based lubricants. It can be inserted as long as 8 hours before intercourse.
  
  
• Disadvantages: The lubricant does not contain spermicide (a substance that kills sperm). The device is difficult to place in the vagina. The inner ring may cause discomfort. Some users consider the female condom awkward. The female condom may cause a urinary tract infection (UTI) if left in the vagina for a long time. 

The diaphragm is a shallow latex cup with a spring mechanism in its rim to hold it in place in the vagina. Diaphragms are manufactured in various sizes. You need a pelvic examination and measurement of the diagonal length of your vaginal canal so your health care provider can determine the correct diaphragm size.
 
You insert the diaphragm with spermicide before sex. The spermicidal cream or jelly is applied to the inside of the dome, which then covers your cervix. Your doctor will show you how to insert it and how to know it is in place.  
 
It prevents pregnancy by acting as a barrier to the passage of semen into the cervix. Once in position, the diaphragm provides effective contraception for 6 hours. After that time, if you have not removed the diaphragm, you will add fresh spermicide with an applicator. After intercourse, the diaphragm must be left in place for at least 6 hours after sex but not more than 24 hours.
 

• How effective: Effectiveness of the diaphragm depends on the age of the user, experience with its use, continuity of use, and the use of spermicide. Typical failure rate within the first year is estimated to be 20%. 
  
  
• Advantages: The diaphragm does not use hormones. The woman is in control of her birth control. The diaphragm may be placed by the woman in anticipation of intercourse.
  
  
• Disadvantages: Prolonged use during multiple acts of intercourse may increase the risk of UTI. Use for longer than 24 hours is not recommended due to the possible risk of toxic shock syndrome. The diaphragm requires professional fitting. Poorly fitted diaphragms may cause vaginal erosions. Diaphragms have a high failure rate. Use of a diaphragm requires brief formal training. The diaphragm may develop odor if not properly cleansed. This method does not protect against STDs.

The cervical cap is a soft cup-shaped latex device that fits over the base of a woman’s cervix. It is smaller than a diaphragm and may be harder to insert. It too must be fitted by your doctor because it comes in different sizes. Its use is derived from the eighteenth- to twentieth-century European practice of placing the rind of a lemon or small orange against the cervix prior to intercourse. 
 
A groove along the inner circumference of the rim improves the seal between the inner rim of the cap and the base of the cervix. Spermicide is needed to fill the cap one third full prior to its insertion. It is inserted as long as 8 hours before sexual activity and can be left in place for as long as 48 hours.
 
A cervical cap acts as both a mechanical barrier to sperm migration into the cervical canal and as a chemical agent with the use of spermicide.
 

• How effective: The effectiveness depends on whether a woman has had children before because it affects the shape of her cervix. With perfect use in the first year, a woman who has not had children has a failure rate of 9% (but more typically 20%), as opposed to 20% in a woman who has delivered children (and more likely 40% failure rate). 
   
• Advantages: It provides continuous contraceptive protection as long as it is in place regardless of the number of intercourse acts. Additional spermicide, unlike for the diaphragm, is not necessary for repeated intercourse. The cervical cap does not involve ongoing use of hormones.
  
  
• Disadvantages: Cervical erosion may lead to vaginal spotting. A theoretical risk of toxic shock syndrome exists if the cervical cap is left in place longer than the prescribed period. The cervical cap requires professional fitting and training for use. Severe obesity may make placement difficult. A relatively high failure rate exists. Women must have a history of normal results on Pap smears. This method does not protect against STDs.

The vaginal sponge, introduced in 1983 and taken off the market shortly after, is making a comeback. The contraceptive was deemed safe by the FDA. However, the plant it was manufactured in was not. A new company has moved production to a new plant and should be available in pharmacies again in fall 2003.
 
The sponge is a soft circular polyurethane device that contains nonoxynol-9, a spermicide. It is disposable and should be discarded after use. It is over the counter, and may be appealing to women who wish to avoid using hormones. 
 
The sponge is inserted into the vagina and placed over the cervix. The polyurethane foam is designed to trap and absorb semen before entry of sperm into the cervix, and the spermicide kills or immobilizes sperm. The sponge has a polyester loop for removal.
 
It offers an immediate and continuous presence of spermicide throughout a 24-hour period. It continues to be effective if sexual intercourse is repeated during this time. The sponge should be left in place for at least 6 hours after sex. It should be removed no more than 30 hours after insertion because of a low risk of toxic shock syndrome.
 
The FDA lists the failure rate for the previously marketed sponge to be 14-28 pregnancies per 100 women per year.

Serious medical risks are rare and include irritation and allergic reactions and difficulty with removal. Toxic shock syndrome is a rare but serious infection that can occur if the sponge is left in place longer than recommended. Nonoxynol-9 provides some protection against pregnancy, but the sponge does not protect against STDs.

|Web Links|

Food and Drug Administration, What Kind of Birth Control is Best for You? 
 
Food and Drug Administration, Birth Control Guide 
 
Henry J. Kaiser Family Foundation, Condoms 

The Nemours Foundation, Birth Control: Cervical Cap; Birth control: Diaphragm; Birth control: Condom 
 
Planned Parenthood, Facts about Birth Control 

male condom, rubber, prophylactic, female condom, diaphragm, vaginal sponge, cervical cap, spermicides, nonoxynol-9, octoxynol, spermicide, birth control overview, birth control barrier methods, contraception

Author: Omnia M Samra, MD, Clinical Instructor, Department of Obstetrics and Gynecology, Medical College of Pennsylvania/Hahnemann University.

Editors: Bryan D Cowan, MD, Director, Division of Reproductive Endocrinology, Professor, Department of Obstetrics and Gynecology, University of Mississippi College of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, ; Lee P Shulman, MD, Professor of Obstetrics and Gynecology, Head, Section of Reproductive Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.