NHS trusts were criticised today for supplying pornography to couples undergoing IVF.
The think tank 2020health.org said the use of porn to help men produce sperm samples promoted "adultery of the mind".
It surveyed 93 NHS trusts that provide fertility services, of which 33 offer pornography in their IVF clinics.
Fifteen trusts got the material free of charge, as donations from patients or publishers, while 18 paid for material, which included DVDs and magazines.
These 18 trusts spent up to £100 each a year on porn, with the average spend on magazines being £21.32 per trust per year and a similar amount for DVDs.
All trusts used magazines and six clinics provided DVDs. Fifteen trusts purchased material from newsagents.
The cost of DVD equipment was generally not reported. However, one trust - the Royal Liverpool Women's NHS Foundation Trust - spent £7,350 on a media suite for its clinic for the viewing of pornography, the study said.
The think tank estimated the NHS spends £700 a year on porn, excluding the cost of viewing equipment.
Its director, Julia Manning, the report's author, said two-thirds of NHS trusts surveyed did not supply porn, showing there was no genuine need for it.
"We know of no government authorisation that sanctioned this, or any exception to any NHS trust's employment terms that allow staff to have pornographic material at work.
"Pornography deprives women of full human status and reduces them to sex objects.
"It gives permission to its consumers to treat women as they are treated in porn.
"And the reality of porn today is that it increasingly uses younger girls and is more violent and extreme.
"(A total of) 77% of the NHS workforce is female and they should never have to work in an environment that endorses pornography.
"That no-one allowed the demeaning impact on female staff to override any spurious claim that this material was necessary is an indictment of the managers of those fertility clinics.
"The public sector workplace should be a leading and inspiring example of a safe and healthy environment, which elevates the dignity and respect of both men and women. The presence of pornography compromises this."
Ms Manning said NHS bosses were effectively telling men they they "should sexually objectify an unknown woman while producing a specimen, rather than think of a partner."
She added: "For the NHS to unnecessarily introduce addictive material - medium that is implicated in causing difficulties to people forming intimate relationships - to patients during their treatment beggars belief.
"And to do this at a time when men are particularly vulnerable, already facing the emotional and physical pressures of possible infertility, is inexcusable."