Diaphragm
vs
External 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.	External Condom A non-hormonal barrier method that also lowers the risk of STIs, available over the counter.
Efficacy	83% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.	87% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.
Cost	$80–$200 Insurance: Usually	$0.5–$3 /per unit Insurance: Varies
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 physical sheath worn over the penis that blocks semen from entering the vagina and reduces skin-to-skin contact that transmits STIs.
Prescription	Required Prescription required	OTC No prescription / OTC
Available Products	2 products	3 products
Side effects	Increased risk of urinary tract infection Vaginal irritation from spermicide Discomfort if not fitted correctly	Rare local irritation from latex or lubricants
Who shouldn't use this	Uterine or cervical anomaly preventing fit Sensitivity to silicone or spermicide Inability to insert or remove reliably	Known allergy to latex (use polyisoprene or polyurethane instead)