Side Effects (see Managing Any Problems)
Some users report the following:
- Changes in bleeding patterns,† including:
- Lighter bleeding and fewer days of bleeding
- Irregular bleeding
- Infrequent bleeding
- Prolonged bleeding
- No monthly bleeding
- Weight gain
- Breast tenderness
Bleeding changes are normal and not harmful. If a woman finds them bothersome, counseling and support can help.
Known Health Benefits and Health Risks
Long-term studies of monthly injectables are limited, but researchers expect that their health benefits and health risks are similar to those of combined oral contraceptives (see Chapter 1 – Combined Oral Contraceptives, Health Benefits and Health Risks). There may be some differences in the effects on the liver, however (see Question 2).
† For definitions of bleeding patterns, see “vaginal bleeding” in the Glossary.