California Code, Family Code - FAM § 9005

(a) Consent of the birth parent to the adoption of the child through a stepparent adoption may not be withdrawn except with court approval. Request for that approval may be made by motion, or a birth parent seeking to withdraw consent may file with the clerk of the court where the adoption petition is pending, a petition for approval of withdrawal of consent, without the necessity of paying a fee for filing the petition. The petition or motion shall be in writing, and shall set forth the reasons for withdrawal of consent, but otherwise may be in any form.

(b) The court clerk shall set the matter for hearing and shall give notice thereof to the probation officer, qualified court investigator, or county welfare department, to the prospective adoptive parent, and to the birth parent or parents by certified mail, return receipt requested, to the address of each as shown in the proceeding, at least 10 days before the time set for hearing.

(c) The probation officer, qualified court investigator, or county welfare department shall, before the hearing of the motion or petition for withdrawal, file a full report with the court and shall appear at the hearing to represent the interests of the child.

(d) At the hearing, the parties may appear in person or with counsel. The hearing shall be held in chambers, but the court reporter shall report the proceedings and, on court order, the fee therefor shall be paid from the county treasury. If the court finds that withdrawal of the consent to adoption is reasonable in view of all the circumstances and that withdrawal of the consent is in the child's best interest, the court shall approve the withdrawal of the consent. Otherwise the court shall withhold its approval. Consideration of the child's best interest shall include, but is not limited to, an assessment of the child's age, the extent of bonding with the prospective adoptive parent, the extent of bonding or the potential to bond with the birth parent, and the ability of the birth parent to provide adequate and proper care and guidance to the child. If the court approves the withdrawal of consent, the adoption proceeding shall be dismissed.

(e) A court order granting or withholding approval of a withdrawal of consent to an adoption may be appealed in the same manner as an order of the juvenile court declaring a person to be a ward of the juvenile court.