Contraception
John L. Washington, MD FACOG

I was recently asked for my opinion about using Depo-Provera for birth control.  The person wanted to know about the side effects and effectiveness of the shots and other hormonal contraceptives.  In this section I will try to outline the general characteristics of various method of contraception that are available.   Please do not mistake this for medical advice, this is for general information only.  You should discuss your decision with your own doctor to find out what is right for you. 

 Hormonal contraceptives work by interrupting the menstrual cycle, preventing contraception, making mucus that is not receptive to sperm and preventing transport of the ovum or implantation.  All of them are very reliable in most people if used correctly.   While hormonal contraceptives are the most popular there are two other types of contraceptives to consider. 

Birth control pills are combination pills of an estrogen and a progestin. They work by fooling the brain into thinking that the ovary is already working at producing its hormones.  The brain then fails to send out the signal to the ovary to produce hormones and at the same time does not signal the ovary to ovulate.  About 90% of women can take birth control pills successfully though some side effects are common in the first couple of months.  Weight gain is common but usually is only a couple of pounds though it may be more.  Most people have some spotting or abnormal bleeding in the first two months.  Many people have very light or absent menses.  Some regard this as an advantage.  The periods are almost always lighter and have much less cramping.  There is sometimes some bloating,   "PMS" symptoms or loss of libido.  There are now at least three types of pills as well as contraceptive patches and a vaginal ring. Most common  is the cyclic pill.  There are countless brands, though the differences are usually small between them.  Some people will tolerate one type better than another and there are some individual differences that may be useful. One pharmaceutical company has marketed a pill pack that omits the placebo week. In this manner the menstrual period only occurs once every three months. Lost of people have always done this with their regular pills, so it really is nothing new. Contraceptive patches are applied weekly so that the contraceptive hormones are absorbed through the skin rather than the stomach. The vaginal ring is inserted monthly and works the same way except that it only has to be placed monthly rather than weekly. The doses of medicine used in these is much smaller than in the pills but the side effects and problems are similar. The risk of blood clots and other liver mediated changes may be less though in the case of the patches there is some recent evidence that the hormone levels may be higher. Some of the newer pills are taken in extended cycles to minimze or eliminate the periods. 

 Mini-pills are progestin only and are less effective than the cyclic, "combination pills". They are used most often in nursing mothers because they do not interfere with the milk supply.  They are particularly sensitive to variation in the time of day that the pill is taken and the use of antibiotics.  Any birth control pill should be taken at the same time of day whenever possible. Antibiotics may interfere with the effectiveness of birth control pills. The mini-pill is especially likely to fail if taken at different times from one day to the next or if antibiotics are taken. Most birth control pills will improve the complexion and regularize abnormal periods.

Depo-Provera is a good option for birth control in that it is reliable and if the shots are given every three calendar months almost never fails. If someone is more than a week late in getting their next shot we usually check a pregnancy test. About 75 to 85% of people who begin using Depo-Provera will continue with it.  The chances of accidental pregnancy while using Depo are vanishingly small.  The usual side effects are irregular spotting and bleeding, usually very light, especially during the first six months, and "PMS" type symptoms, which are rather unpredictable and variable. Some people will have abnormal and variable weight gain.  A small percentage, 5 to 15 percent in my experience, will have bloating or swelling or crankiness enough to make them want to stop the medicine. Osteoporosis is a long term concern  The absence of a period is not a problem as far as your health is concerned; though it may make you uncomfortable to have such a change in your routine.  The period stops because the effect of estrogen on the lining of the uterus is blocked and the tissue never develops, not because the menstruation is retained inside of you as many people have worried.  The length of time that it takes for the medicine to wear off varies from person to person and with the length of time you have been on it.  Most people resume normal cycles and are fertile within the first year after discontinuing the shots.   Some people take much longer and may need other medicines to stimulate the return of the periods.  This may point to an underlying hormonal problem that this person has.  There aren't really any other shots for birth control.  Lupron and Zoladex both stop the periods and cause temporary infertility but they are used for treating endometriosis and similar problems.  They generally cost $300 a month and can only be used for 6 months at a time. 

The Norplant is a set of small plastic capsules that are injected under the skin of the upper arm.  They cause infertility for about 5 years before they have to be removed and replaced. Their failure rate is low.   They also can cause irregular periods and headaches.   They are easy to insert and may be hard to remove. A newer version is now available that uses only a single capsule.

 All of the hormonal methods of birth control will have similar side effects, irregular bleeding bloating, swelling, weight gain and "PMS."  

There was a monthly injection called Lunelle. This injection is a combination of estrogens and progestin just like most of the other hormonal contraceptives. It was  given once a month. A period occurs about a week after the injection. I don't think it is available now. It was never very popular. 

The Nuva-ring is a combination hormone contraception similar to the Ortho Evra Patches. In both of these products contraception is similar to birth control pills but the blood levels of the hormones are very stable. The dosage can be manipulated to avoid periods if this is desired. 

About 90 percent of people who decide to use a hormonal contraceptive use the pills.  People who have problems with side effects on the pills, who can't remember to take the pills reliably or who are over 35 and smoke are good candidates for the Depo-Provera.  Almost all birth control ends up costing $15 to $40 a month.  Birth control pills cost $15 to $45 depending on the brand.

Another option is barrier contraception, condoms, spermicidal foam, suppositories or the diaphragm.  These are less expensive if sex is less common but they require discipline.  They are totally ineffective unless used every time!  If you get carried away by the moment or sometimes "feel lucky" you will soon be pregnant. When used reliably the barrier methods are good but not great.  The major advantage is that they provide some protection against sexually transmitted diseases and other methods do not.

Intrauterine contraceptive devices, IUD's, are less popular now than they were twenty five years ago when pills were more primitive.  IUD's are small plastic devices, with a string for retrieval, that are inserted by the doctor into the uterus.  It is not well established how they prevent pregnancy.  It may be by interfering with sperm passage or it may be by not allowing the fertilized egg to implant.  There are two types available now, the Paragard and the Mirena  The Paragard can be left in place for 10 years but the Mirena must be replaced every five years.  The advantage of the Mirena  is that it tends to make periods lighter and less crampy, and it may even be used to treat heavy periods. The  Paragard may worsen the periods somewhat.   Either one is generally reliable against normal pregnancy but may not prevent ectopic, tubal pregnancies.  Rarely the uterus may be perforated when the device is inserted and they may be expelled spontaneously from the uterus.  If one gets an infection such as gonorrhea or chlamydia while the IUD is in place serious complications, tubal infection or pelvic inflammation is more common.

Almost anyone can find a method of birth control that will work for them with a minimum of side effects.  You should talk to your doctor about your own situation and particular needs.