DiaphragmvsInternal Condom

A side-by-side comparison of two birth control methods — efficacy, cost, how they work, and who shouldn't use them.

Side-by-side comparison

Method	Diaphragm A reusable silicone dome that covers the cervix to block sperm, used with spermicide each time you have sex.	Internal Condom A soft pouch worn inside the vagina that blocks sperm and protects against STIs, available by prescription.
Efficacy	83% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.	79% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.
Cost	$60–$112 Insurance: Usually	$0–$4 /per unit Insurance: Usually
Duration	Reusable for 1-2 years (replace every 1-2 years or sooner if damaged)	Single use
Reversibility	Reversible	Reversible
STI Protection	No	Yes
How it works	A reusable silicone dome covers the cervix to block sperm from entering the uterus. Used with spermicide for added effectiveness.	A soft, loose-fitting nitrile pouch lines the vagina and collects semen. The inner ring anchors it at the cervix and the outer ring stays outside the vaginal opening.
Prescription	Required Prescription required	Required Prescription required
Side effects	Increased risk of urinary tract infection Vaginal irritation from spermicide Discomfort if not fitted correctly	Mild irritation or discomfort Noise during use if not positioned correctly Slippage with incorrect insertion
Who shouldn't use this	Uterine or cervical anomaly preventing fit Sensitivity to silicone or spermicide Inability to insert or remove reliably	Sensitivity to nitrile (rare)

Key differences

Diaphragm is more effective (83% vs 79% typical use). Diaphragm duration: Reusable for 1-2 years (replace every 1-2 years or sooner if damaged). Internal Condom duration: Single use. Only Internal Condom protects against STIs. Diaphragm: costs $60–$112. Internal Condom: costs $0–$4 per unit.