106. A marriage which takes place after 1st June 1981 shall be voidable on the following grounds only:
that the marriage has not been consummated owing to the incapacity of either party to consummate it;
that the marriage has not been consummated owing to the wilful refusal of the defendant to consummate it;
that either party to the marriage did not validly consent to it, whether in consequence of duress, mistake, mental disorder or otherwise;
that at the time of the marriage either party, though capable of giving a valid consent, was suffering (whether continuously or intermittently) from mental disorder within the meaning of the Mental Health (Care and Treatment) Act 2008 of such a kind or to such an extent as to be unfit for marriage;
that at the time of the marriage the defendant was suffering from venereal disease in a communicable form;
that at the time of the marriage the defendant was pregnant by some person other than the plaintiff.