Speaking in parliament Timpson said there has been a sharp increase in the use of SGOs for children under the age of one.
He added that, in light of court judgments from 2013, the orders, which are used predominantly to give relatives of a child legal responsibility for their upbringing, are often now regarded as a “default option” for children.
Timpson said that, through a review of SGOs launched in July, government hopes to make improvements to the decision-making process around SGOs, as well as subsequent support for guardians.
Earlier this week CYP Now reported on fears that some vulnerable children are being placed in inappropriate arrangements due to a preference among family judges for special guardianship orders.
A Department for Education report stated that SGOs are sometimes being granted to carers who are not members of the extended family and who have no existing relationship with the child.
Timpson said: “It is now a decade since [SGOs] were introduced by the last Labour government, and it is time for us to have a close and proper look at the consequences of their introduction.
“For instance, we have seen a sharp increase, of 64 per cent, in the use of SGOs for children under the age of one, which is not what was originally intended or envisaged when the legislation was introduced.
“We have also seen, through the court judgments of Re B and Re B-S, SGOs often now being regarded as a default option when considering a child’s long-term future.
“We also have a disparity in respect of the level of assessment that there is of the potential placement for a child in a special guardianship placement, as opposed to adoption.
“We will be working carefully with the expert group that we have set up to make sure that, whether in relation to the decision around an SGO or the subsequent support, we make improvements from where we first started.”
The number of SGOs made is on the rise. In 2014 a total of 3,300 were made, compared with 1,290 in 2010.
Andy Elvin, chief executive of The Adolescent and Children’s Trust (Tact), described Timpson's comments in parliament as "encouraging".
"Hopefully it means he's going to take forward the recommendations," Elvin said.
Elvin added that while there are concerns about the use of SGOs in some circumstances, they are a valuable route to permanence for many children.
He said he believes discussions around improvements include making sure special guardians receive support to deal with contact arrangements with the natural parents once the order has been made.
He added that the judiciary is also keen for birth parents to have a better understanding of what an SGO means.
There is also a desire for the way special guardians are assessed to be improved.
"There is a recognition that the difference in depth and quality between assessments for adoption and fostering and those for SGOs is not sustainable," he said.
"We certainly know of cases where [the assessment] is not sufficiently in-depth, and the worry is that will lead to a spate of breakdowns in the next five or 10 years."
Today (18 September) is the deadline for submissions for evidence for the government review of SGOs.