Oh my goodness.
Did you realise that no form of contraception is 100% successful? Even if pills are taken, condoms are used, even sterilisation isn't 100% successful. An unplanned pregnancy is not normally the result of a woman lying about contraception.
Men have the right to have a vasectomy to help reduce the chance of conceiving a child, to use as many forms of contraception as they wish, or to abstain from sex, as do women.
A thought experiment...if men were allowed the right to financially "abort" their unborn child, but in order to do so, this had to be recorded on a public register, do you think many men would take it up? If not, why not? Because they wanted to hide their indiscretions under the carpet? Do you think they'd have good chances for a new relationship if their new girlfriend could see they'd ditched their ex when she got pregnant?