Green’s Dictionary of Slang

Eve’s custom house n.

the vagina.

c.1786		Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: Eve’s Custom-house, where Adam made his first entry. The monosyllable.
1788, 1796		Grose Classical Dict. of the Vulgar Tongue (2nd, 3rd edn).
1790		‘Bumper Allnight. Esquire’ Honest Fellow 216: Sentiments [...] Eve’s custom house, where Adam made the first entry.
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1838		Crim.-Con. Gaz. 1 Dec. 120/1: Heer’s Bathsheba’s cockpit, where David stood sentry, / Eve’s custom house, where Adam made the first entry.
1840		[as 1838].
1890–1904		Farmer & Henley Sl. and Its Analogues.