What is the Shot?
The birth control shot is a hormonal injection administered to a woman by her healthcare provider every twelve weeks. It is generally performed at the doctor’s office, although it is possible to obtain an at-home prescription if you feel comfortable injecting yourself. The shot releases the hormone progestin into the bloodstream. This suppresses ovulation, meaning that there is no egg present in the uterus for sperm to join with. It also thickens the cervical mucus, making it more difficult for sperm to enter the uterus and decreasing the likelihood that fertilization will occur if ovulation is not suppressed.
How effective is the Shot?
Used perfectly, the shot is over 99% effective, meaning that less than 1 in 100 women will get pregnant each year. With normal use, the effectiveness decreases slightly, with about 94% effectiveness. This difference is due mainly to women forgetting to return to their doctor for the shot, which can lead to ovulation and unplanned pregnancies. Although the shot is effective for up to 14 weeks, this form of birth control is most effective when injected at regular, 12-week intervals. Most healthcare providers will ask a woman who has not had an injection in over 13 weeks to take a pregnancy test to ensure that she is not pregnant. Certain antibiotics and other medications can also make the shot less effective, so it is important to speak with your doctor before combining medication with your birth control. The shot does not protect against STDs.
What are myths associated with the Shot?
1. The shot causes osteoporosis.
This myth is an overstatement of some data found in recent studies surrounding the birth control shot. A somewhat common side effect of the shot is a slight thinning of bone density, which can increase the fragility of the bones. However, the same studies have revealed that women who reported decreased bone density also saw the minerals come back after discontinuing use of the shot. This means that while the shot may temporarily cause a slight decrease in bone density, it will not cause long-term bone problems. Additionally, women using the shot can take vitamin and mineral supplement tablets to counteract this effect.
2. The shot can cause fertility problems later on.
As with most forms of birth control, there is a fear that the use of hormones will interfere irreversibly with the body’s natural system. In the case of the shot, this fear was compounded by the fact that after an injection a woman must wait at least three months before she is able to get pregnant again, because ovulation does not occur while the hormones are active in her body. All ovulation-suppressing forms of birth control have the potential to cause some lag in a woman’s ovulatory cycle, but because the shot necessarily halts ovulation for three months, women who wish to conceive must plan their short-term plans for pregnancy a bit in advance. For this reason, women who are planning to get pregnant within a year are not advised to use the shot as their main form of contraception.
3. The shot makes you gain weight.
While it is true that certain women find that they have gained weight while using the shot, there is no clear causal relationship between injection and weight gain. Some possibilities are increased water retention that can make women feel bloated, and a change in appetite caused by the introduction of hormones into the system. Staying hydrated can help bring down bloating if this is the issue. Additionally, while change in appetite can be a side effect, women affected are not necessarily more likely to experience an increased rather than a decreased appetite while using the shot.
4. The shot works by causing abortions.
There is absolutely no validity to this myth, which is common among many forms of birth control. The shot suppresses ovulation, meaning that women using the shot do not ovulate. If ovulation and fertilization do occur while a woman is using the shot, the embryo will implant in her uterus normally, and will not be harmed by the hormones. Women who may be pregnant should not continue to get injections; they will not terminate a current pregnancy.
What are disadvantages of the Shot?
The biggest disadvantage associated with the shot is the potential inconvenience of visiting the doctor’s office every three weeks to get the injection. Although self-injection is possible, many women do not feel comfortable giving themselves the shot and opt to have the injection performed by a doctor.
The most common physical side effects are breast swelling and tenderness and irregular periods particularly during the first year of use. A change in menstruation is common, although some women experience lighter periods with the shot and others report heavier periods, so there is no standard shift. Many women experience some amount of breakthrough bleeding, or light bleeding between periods, particularly within the first year. Some women will stop menstruating completely after their first year using the shot.
A less common but nonetheless notable side effect of the shot is a change in sex drive. Some women report a lowered sex drive after beginning the shot, and some find it more difficult to become physically aroused while using this form of birth control.
Where can I get the Shot?
The shot is available through most doctors’ offices, where they will fill the prescription and perform the injection. Talk to your doctor if you feel that the shot might be the right choice for your birth control.