DiaphragmvsSponge

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.	Sponge A soft foam disc placed deep in the vagina before sex. It covers the cervix and contains spermicide.
Efficacy	83% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.	Least effective see details Least effective: under 90 out of 100 people successfully prevent pregnancy per year.
Cost	$60–$112 Insurance: Usually	$15–$20 /per package Insurance: No
Duration	Reusable for 1-2 years (replace every 1-2 years or sooner if damaged)	Single use (can be left in place up to 24 hours and for multiple acts of sex)
Reversibility	Reversible	Reversible
STI Protection	No	No
How it works	A reusable silicone dome covers the cervix to block sperm from entering the uterus. Used with spermicide for added effectiveness.	A polyurethane foam disc impregnated with spermicide is placed over the cervix before sex. The spermicide kills or disables sperm and the physical barrier blocks sperm from entering the uterus.
Prescription	Required Prescription required	OTC No prescription / OTC
Side effects	Increased risk of urinary tract infection Vaginal irritation from spermicide Discomfort if not fitted correctly	Vaginal irritation or dryness Increased risk of urinary tract infection Rare allergic reaction
Who shouldn't use this	Uterine or cervical anomaly preventing fit Sensitivity to silicone or spermicide Inability to insert or remove reliably	Allergy to nonoxynol-9, benzalkonium chloride, or other spermicide ingredients History of toxic shock syndrome Active vaginal infection Inability to insert or remove reliably High risk of HIV exposure (frequent nonoxynol-9 use may increase vaginal irritation; CDC cautions)

Key differences

Diaphragm duration: Reusable for 1-2 years (replace every 1-2 years or sooner if damaged). Sponge duration: Single use (can be left in place up to 24 hours and for multiple acts of sex). Diaphragm requires a prescription; Sponge does not. Diaphragm: costs $60–$112. Sponge: costs $15–$20 per package.