Where the law of adoption is not final, natural parents may reclaim their child, and if the foster parents also feel they have a strong claim to the child, a tug-of-war may develop with damaging effects on the child. In some situations the law demands that suitable foster parents should be found before the mother gives her consent to adoption. By the time that the adoption order can be made, she may have changed her mind, causing anxiety both to herself and to the prospective foster parents, again with adverse effects on the child. In certain countries there is a probationary period for adoption before it becomes final. If during this time the authorities feel that the foster parents are unsuitable, or if the foster parents are not happy with the child, the adoption may be annulled and the child returned to an institution.
In Sweden adoptions never become irrevocable. Many countries, including the USA, Germany, UK and Scandinavian countries, demand a supervisory period before adoption is confirmed. In England, foster parents must be found before the mother gives consent to the adoption.