Conn. Gen. Stat. § 46b-512: Consent to assisted reproduction.

(a) Except as provided in subsection (b) of this section, the consent described in section 46b-511 shall be in a record signed by a person giving birth to a child conceived by assisted reproduction and a person who intends to be a parent of the child.

(b) Failure to consent in a record as required by subsection (a) of this section, before, on or after the date of birth of the child, shall not preclude the court from finding consent to parentage if the person who gave birth or the person who intends to be a parent of the child proves by clear and convincing evidence the existence of an agreement that the person and the person giving birth intended they both would be parents of the child.