Vaginal pH ModulatorvsWithdrawal

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	Vaginal pH Modulator A prescription gel used before sex that keeps vaginal pH acidic to disable sperm.	Withdrawal The man withdraws his penis from the vagina before ejaculation to reduce the chance of sperm reaching the egg.
Efficacy	86.3% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.	80% typical use Least effective: under 90 out of 100 people successfully prevent pregnancy per year.
Cost	$0–$400 /per package Insurance: Usually	$0 Insurance: Varies
Duration	Single use (effective for 1 hour)	Per act
Reversibility	Reversible	Reversible
STI Protection	No	No
How it works	A gel containing lactic acid, citric acid, and potassium bitartrate maintains an acidic vaginal pH that disables sperm and reduces their motility. It also acts as a physical barrier to sperm movement.	The man withdraws his penis from the vagina before ejaculation to keep semen out of the vagina. Pre-ejaculate may contain some sperm, which is why perfect use is not 100%. A 2024 pilot study found sperm in about 13% of pre-ejaculate samples, though roughly 75% of participants had no sperm in any sample.
Prescription	Required Prescription required	OTC No prescription / OTC
Side effects	Vaginal burning or irritation Increased risk of urinary tract infection Rare allergic reaction	None reported
Who shouldn't use this	Recurrent UTIs or urinary tract abnormalities (FDA label says avoid use)	Partner unable to withdraw consistently before ejaculation Need for highly effective contraception

Key differences

Vaginal pH Modulator is more effective (86.3% vs 80% typical use). Vaginal pH Modulator duration: Single use (effective for 1 hour). Withdrawal duration: Per act. Vaginal pH Modulator requires a prescription; Withdrawal does not. Vaginal pH Modulator: costs $0–$400 per package. Withdrawal: costs $0.