Why Isn't My Menstrual Cup Working Even When It's Fully Open?

A menstrual cup that appears fully open but still leaks usually has a seal or fit issue. Here are the most common causes and solutions.

Common Causes of Leaks

1. Incorrect Placement (Too Low): The cup must sit high in the vaginal canal, with the rim behind the pubic bone. If it sits too low, the seal breaks. Fix: Insert higher, then rotate to ensure unfolding.
2. Incomplete Seal (Suction): The cup must fully expand and create light suction. Fix: After insertion, run a finger around the rim to check for folds; pinch base and rotate; bear down gently to help it open.
3. Weak Pelvic Floor Muscles: Poor tone reduces cup retention, especially with heavy flow or bearing down. Fix: Daily Kegel exercises; consider a firmer cup.
4. Heavy Menstrual Flow: Cup capacity (typically 20–30 mL) may be exceeded. Fix: Empty more frequently (every 4–6 hrs); use a high-capacity cup (30–40+ mL) for heavy days.
5. Anatomical Variations: Tilted uterus, low cervix, vaginal vault prolapse, or post-hysterectomy changes can prevent sealing. Fix: Try a shorter/wider cup; consult a pelvic floor PT or clinician.
6. Cervix Positioning: If the cervix sits inside the cup, it displaces capacity and breaks the seal. Fix: Ensure cup sits below the cervix; use a shorter cup if cervix is low.

Troubleshooting Checklist

• ☐ Cup fully unfolded? (Feel rim—no dents)
• ☐ Rim behind pubic bone?
• ☐ Light suction when tugging stem?
• ☐ Cervix not inside cup?
• ☐ Emptying often enough?

When to Seek Professional Help

If leaks persist after trying adjustments, consult:

• Menstrual cup coach/educator (many offer virtual fitting).
• Pelvic floor physical therapist.
• Gynecologist—to rule out anatomical issues (prolapse, fibroids, stenosis).

Most leaks are fixable with technique tweaks or a different cup size/firmness. Don't give up—menstrual cups are highly effective with proper fit.