(1) In this Act—
"excess ART embryo "means a human embryo that—
(a) was created, by assisted reproductive technology, for use in the assisted reproductive treatment of a woman; and
(b) is excess to the needs of—
(i) the woman for whom it was created; and
(ii) her partner (if any) at the time the embryo was created.
(2) For the purposes of paragraph (b) of the definition of excess ART embryo , a human embryo is excess to the needs of the persons mentioned in that paragraph at a particular time if—
(a) each such person has given written authority for use of the embryo for a purpose other than a purpose relating to the assisted reproductive treatment of the woman concerned, and the authority is in force at that time; or
(b) each such person has determined in writing that the embryo is excess to their needs, and the determination is in force at that time.