Side Effects, Health Benefits, and Health Risks

Side Effects (see Managing Any Problems)

Most users report some changes in monthly bleeding. †

  • Typically these include, with DMPA:
    First 3 months:

    • Irregular bleeding
    • Prolonged bleeding

    At one year:

    • No monthly bleeding
    • Infrequent bleeding
    • Irregular bleeding
  • NET-EN affects bleeding patterns less than DMPA. NET-EN users have fewer Side effectsdays of bleeding in the first 6 months and are less likely than DMPA users to have no monthly bleeding after one year.

Bleeding changes are normal and not harmful. If a woman finds them bothersome, counseling and support can help.

Some users report the following:

  • Weight gain (see Question 5)
  • Headaches
  • Dizziness
  • Abdominal bloating and discomfort
  • Mood changes
  • Less sex drive

Other possible physical changes:

Why Some Women Say They Like Progestin-Only Injectables
  • Requires action only every 2 or 3 months. No daily pill-taking.
  • Do not interfere with sex    
  • Are private: No one else can tell that a woman is using contraception
  • Stop monthly bleeding (for many women)      
  • May help women to gain weight     

Known Health Benefits

Known Health Risks

DMPA

Help protect against:

  • Risks of pregnancy
  • Cancer of the lining of the uterus (endometrial cancer)
  • Uterine fibroids

May help protect against:

  • Symptomatic pelvic inflammatory disease
  • Iron-deficiency anemia

Reduces:

  • Sickle cell crises among women with sickle cell anemia
  • Symptoms of endometriosis (pelvic pain, irregular bleeding)

 

None

NET-EN

Helps protect against:

  • Risks of pregnancy
  • Iron-deficiency anemia

 

None

NET-EN may offer many of the same health benefits as DMPA, but this list of benefits includes only those for which there is available research evidence.

DMPA for Subcutaneous Injection

DMPA is now available in a special formulation, called DMPA-SC, that is meant only for subcutaneous injection (just under the skin) and not for injection into muscle. Subcutaneous injection is easier to learn than intramuscular injection.

DMPA-SC is available in two injection systems—in the Uniject device and in prefilled, single-dose, conventional syringes. Both have short needles meant for injection just below the skin.

With the Uniject system, the user squeezes a flexible reservoir that pushes the fluid through the needle. DMPA-SC in the Uniject system is marketed under the brand name Sayana Press. This product may be particularly useful for community-based programs. Also, women can easily learn to give themselves subcutaneous injections with this system (see instructions).

† For definitions of bleeding patterns, see “vaginal bleeding.”