Birth control and you: The shot
THE birth control shot can help prevent pregnancy for up to three months because it contains a synthetic hormone called progestin which blocks ovulation. The injection is best known by its brand name Depo-Provera and requires a prescription. It is generally administered at the start of the menstrual cycle.
“The fact that there is no oestrogen in the injection makes it a suitable choice for women who cannot take oestrogen. This includes women who have a history of deep vein thrombosis or pulmonary embolism (clot in the leg, veins or in the lungs), women who have oestrogen-dependent cancers such as breast cancer or sickle cell anaemia, where there is a high risk of developing a clot in the leg, and women who have severe hypertension,” explained obstetrician/gynaecologist Dr Sharmaine Mitchell.
“It is unlikely that any patient on the Depo Provera will ovulate and this method of contraception is equal to that of sterilisation (tubal ligation),” she said.
The progestin in the shot works by keeping eggs from leaving the ovaries and making the cervical mucus thicker so that sperm won’t be able to get to the eggs.
It is important to note that Depo-Provera is not the only injectable form of contraception. There is also MESIGYNA, which is a monthly injection that contains both oestrogen and progesterone, however, Depo-Provera remains more popular for a variety of reasons.
Here are some of the advantages of this form of contraception, as well as the disadvantages.
Advantages
1. You won’t have to worry about getting pregnant for the next three months.
2. It is one of the most effective contraceptive methods; 99 per cent success rate.
3. It provides a certain level of privacy.
4. Depo-Provera does not interfere with sexual activity.
5. It is ideal for patients with heart disease, sickle cell anaemia and patients with a history of clot in the legs or lungs.
6. It increases the quantity of milk in nursing mothers, whereas oral contraception could cause a reduction in the volume of breast milk.
Disadvantages
1. It does not provide protection against sexually transmitted diseases. As such, it is important that you use a condom during sexual intercourse.
2. It usually causes several side effects such as headaches, acne, weight gain, osteoporosis, depression, change in appetite, hair loss and irregular menstruation. “Women are usually advised that in the first year of use this may be associated with irregular bleeding from the uterus. This usually settles down by the third injection and then there is no period,” Dr Mitchell pointed out.
3. You have to wait for about six months and sometimes longer to get pregnant after the last shot has been taken.
