Injectable contraceptives containing synthetic hormones are injected intramuscularly for contraception. The mechanisms of contraceptive actions include suppression of ovulation and thickening of cervical mucus hence rendering it impervious to sperms. There are Progestogen Only Injectables and Combined Injectable Contraceptives (CIC). If the first injection is given within the first 7 days of menses, it will offer immediate protection. Injection must be given regularly and at fixed intervals without interruption.
Women with confirmed pregnancy, less than 6 weeks postpartum, and had breast cancer, severe hypertension, cerebrovascular or coronary artery disease, thromboembolism/deep vein thrombosis, complicated valvular heart disease, diabetes with complications, active hepatitis, severe liver cirrhosis, benign or malignant liver tumour are contraindicated for the use of injectable contraceptives. Progestogen Only Injectable is preferred to CIC in breastfeeding women. Clients might experience a delay in the return of ovulation following the discontinuation of Progestogen Only Injectables. Normal ovulation usually returns 6-12 months after the cessation of Progestogen Only Injectables. Both injectables will not cause infertility.
Progestogen Only Injectables
Progestogen Only Injectables contain progestogen only. Each injection is effective for 3 months. Research conducted overseas and in local Chinese showed that women receiving long-term Depo-provera will have lower bone mass than other women. Therefore we suggest women to have adequate calcium intake, sun exposure and do weight bearing exercise everyday. If you have other risk factors for osteoporosis like history of fracture, alcoholism, smoking, low body mass index, inadequate calcium intake, family history of osteoporosis, endocrine diseases e.g. thyroid disease, parathyroid disease or on long-term steroid, please discuss with our doctor to see if you can use Depo-provera. Other side effects include, but are not limited to, weight gain, headache, dizziness, breast tenderness, fluid retention and mood changes. There may be irregular menses, reduced menstrual flow or amenorrhoea following the injection.
Combined Injectable Contraceptives
Combined Injectable Contraceptives contain estrogen and progestogen. Each injection is effective for 1 month. Minor side effects include, but are not limited to, menstrual irregularities, nausea, vomiting, headache, dizziness, breast tenderness, fluid retention and mood changes. Long-term side effects are similar to combined oral contraceptive pills.