What is the most common cause of postpartum vaginal (PV) bleeding in women who have stopped injectable contraception (e.g. Depo-Provera (medroxyprogesterone)) between 1 to 6 months and are still in their reproductive age?

Most Common Causes of Vaginal Bleeding After Stopping Injectable Contraception

The most common cause of vaginal bleeding in women who have stopped injectable contraception (Depo-Provera) between 1 to 6 months is the return of normal menstrual cycles, often characterized by irregular bleeding patterns as the hypothalamic-pituitary-ovarian axis resumes normal function.

Understanding Post-Injectable Contraception Bleeding

When women discontinue depot medroxyprogesterone acetate (DMPA, Depo-Provera) injections, their bodies undergo a transition period as hormone levels adjust. This transition typically manifests in the following ways:

Common Bleeding Patterns After Stopping DMPA (1-6 months)

1. Irregular bleeding patterns

   • Unpredictable timing of bleeding episodes
   • Variable flow (light to heavy)
   • Spotting between periods

2. Delayed return to regular cycles

   • The contraceptive effect of DMPA can persist for some time after discontinuation 1
   • Some women may experience a delay of several months before regular cycles resume

3. Gradual normalization

   • Bleeding patterns typically become more regular over time
   • Most women return to their pre-DMPA bleeding patterns within 6-12 months

Differential Diagnosis

While irregular bleeding is expected during this transition period, other causes should be considered:

1. Retained Products of Conception (RPOC) - If the woman had a recent pregnancy

   • Most common cause of secondary postpartum hemorrhage 2
   • Presents as heavy, persistent bleeding

2. Endometritis/Infection

   • Leading cause of secondary postpartum hemorrhage (64% of cases) 2
   • Often accompanied by pain, fever, or discharge

3. Subinvolution of the placental bed - In postpartum women

   • Failure of the placental site to heal properly 1
   • Can be difficult to distinguish from vascular abnormalities

4. Structural abnormalities

   • Polyps, fibroids, or adenomyosis
   • May become more apparent as hormonal suppression wears off

5. Pregnancy-related bleeding

   • New pregnancy (including ectopic)
   • Should be ruled out in any woman with unexpected bleeding

Evaluation Approach

For women experiencing vaginal bleeding 1-6 months after stopping DMPA:

1. Rule out pregnancy

   • Pregnancy test is essential
   • Ultrasound if pregnancy is confirmed to rule out ectopic pregnancy 3

2. Assess bleeding pattern

   • Duration, frequency, and heaviness of bleeding
   • Associated symptoms (pain, fever, discharge)

3. Transvaginal ultrasound if bleeding is:

   • Heavy or prolonged
   • Associated with pain
   • Concerning for structural abnormalities

4. Laboratory evaluation

   • Complete blood count if bleeding is heavy
   • Thyroid function tests if other symptoms of thyroid dysfunction are present
   • Coagulation studies if bleeding is severe

Management Considerations

Management depends on the severity of bleeding and underlying cause:

1. For typical post-DMPA irregular bleeding:

   • Reassurance that patterns typically normalize over time
   • Monitoring for worsening symptoms

2. For heavy or prolonged bleeding:

   • NSAIDs may help reduce flow
   • Short-term hormonal therapy (e.g., combined oral contraceptives) can stabilize the endometrium
   • Follow-up to ensure resolution

3. For structural abnormalities:

   • Targeted treatment based on findings

Important Caveats

• The return to fertility after DMPA discontinuation is variable and may be delayed compared to other contraceptive methods
• Bleeding between 6-8 weeks postpartum in fully breastfeeding women is common (occurs in nearly half of women) but does not necessarily indicate return to fertility 4
• Abnormal uterine bleeding is a common but rarely dangerous side effect of hormonal contraception and its discontinuation 5

Remember that while irregular bleeding after stopping DMPA is expected, persistent heavy bleeding or bleeding associated with other concerning symptoms warrants further evaluation to rule out pathological causes.