Barrier Methods of Birth Control
Melissa Conrad Stöppler, MD
Melissa Conrad Stöppler, MD
Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.
William C. Shiel Jr., MD, FACP, FACR
William C. Shiel Jr., MD, FACP, FACR
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Introduction to birth control
If a woman is sexually active and she is fertile and physically able to become pregnant, she needs to ask herself, "Do I want to become pregnant now?" If her answer is "No," she must use some method of birth control (contraception).
Terminology that is used to describe birth control methods includes contraception, pregnancy prevention, fertility control, and family planning. But no matter what terminology, sexually active people can choose from a number of methods to reduce the possibility of their becoming pregnant. Nevertheless, no method of birth control available today offers perfect protection against sexually transmitted infections (sexually transmitted diseases, or STDs), except abstinence.
In simple terms, all methods of birth control are based on either preventing a man's sperm from reaching and entering a woman's egg (fertilization) or preventing the fertilized egg from implanting in the woman's uterus (her womb) and starting to grow. New methods of birth control are being developed and tested all the time. And what is appropriate for a couple at one point may change with time and circumstances.
Unfortunately, no birth control method, except abstinence, is considered to be 100% effective.
Barrier methods of contraception
Barrier methods of contraception work by creating a physical barrier between sperm and egg cells so that fertilization cannot occur. The most common forms of barrier contraception are condoms (male and female), diaphragm, cervical cap, and contraceptive sponge.
Spermicides, a form of chemical contraceptive that work by killing sperm, are often combined with barrier methods of contraception for greater effectiveness.
While barrier methods of contraception generally do not have the side effects of hormonal contraceptives, some forms of barrier contraception (contraceptive sponges and condoms) may be obtained without a prescription.
The only medical contraindication to the use of barrier contraception is latex allergy (when using latex condoms). However, with the exception of male and female condoms that can provide protection against infection with sexually-transmitted diseases (STDs), most methods of barrier contraception are not effective in preventing STDs.
During sexual intercourse, hundreds of millions of sperm are normally released into a woman's vagina. The large majority of these sperm die. They die because of the unfriendly environment of the vagina, which is acidic, and because the mucus in the cervix above the vagina acts as a selective filter for the sperm. Only about 1% of all the sperm released in an ejaculation successfully pass through the woman's vagina and cervix to reach the uterus (the womb). However, it only takes one sperm to fertilize the ovum (the egg) and to achieve conception.
Spermicides are a type of contraceptive agent that work by killing sperm.
Spermicides need to be in place in a woman's vagina before intercourse if they are to prevent viable sperm from reaching her uterus. Spermicides come in a wide variety of forms, including jellies, creams, foams, films, and suppositories. The active ingredient in essentially all spermicides is Nonoxynol-9. This is a detergent-like chemical that kills sperm.
Once placed inside the vagina, the spermicide melts into a liquid that coats the vagina in order to set up a chemical barrier between the sperm and the cervix. Spermicidal foams are more effective than creams or jellies. Not only is it possible to achieve a better distribution with foam, but foam adheres better to the vaginal walls and cervix.
Suppositories are solid or semi-solid and need to be inserted in the vagina 15 minutes before intercourse in order to liquefy with vaginal moisture.
Vaginal contraceptive film needs to be in place in the vagina about 5 minutes prior to sexual intercourse in order to liquefy and become effective.
Spermicides are like all other methods of birth control in that they must be used properly in order to prevent pregnancy. Each type of spermicide has a unique method of use. For example, spermicidal creams, gels, and foam need to be deposited high up in the vagina near the cervix. Spermicidal suppositories must be unwrapped and inserted in the vagina. Squares of spermicidal film should be inserted into the vagina with a woman's finger. It is important to follow exact instructions on the package for each different type of spermicide.
A spermicide should be placed in the vagina prior to the man's penis getting anywhere near the vagina. It is a common mistake for a couple to wait too long before using the spermicide.
There are two basic concerns with any given spermicide. 1) How long the spermicide stays in the desired place; and 2) how long the spermicide is active in killing sperm. Therefore, the timing of spermicide use must take into account both of these factors.
In general, spermicides tend to be effective soon after their application. They can be inserted 15 minutes or more before intercourse. However, if there is a significant delay before intercourse (for example an hour), more spermicide must be added.
A fresh application of spermicide must also be used for each act of intercourse.
Douching should be avoided for at least 8 hours after the last intercourse.
The effectiveness of spermicides in preventing pregnancy varies from 70 to 90%. This depends on the amount of spermicide and how it is used, the timing of use prior to intercourse, and how well the instructions on the package are followed.
Spermicides should not be used as protection for the woman or man against sexually transmitted infections (sexually transmitted diseases, or STDs). While spermicides may be partially protective against certain organisms that cause sexually transmitted infections, including chlamydia and gonorrhea, they also do not protect against the human Immunodeficiency virus (HIV) infection.
The main objection voiced about spermicides is that they are "messy." A small percent (2% to 4%) of people may have an adverse reaction to Nonoxynol-9, which is experienced as an irritation or a burning sensation.
Spermicides, however, have some positive features. They are relatively inexpensive and they are available over-the- counter (OTC) without a prescription.
Note that some lubricating jellies also available over-the-counter do not contain spermicide and are not meant to be used as a form of birth control. It is important to check the information on the package to be sure that the product contains spermicide or that the word "contraceptive" appears on the label.