The decision not to prosecute two doctors accused of arranging abortions based on the sex of an unborn baby remains the right one, the country's top prosecutor has said.
In a letter to Attorney General Dominic Grieve, Director of Public Prosecutions Keir Starmer QC said he was sure the decision was "properly taken and sound".
The letter comes as the Crown Prosecution Service published more detailed reasons for the decision not to prosecute the two doctors for attempting to procure a miscarriage unlawfully.
Last month Mr Starmer said he would make the detailed reasons public after Health Secretary Jeremy Hunt called for "urgent clarification" on the decision.
An undercover investigation by the Daily Telegraph last year involved secretly filming doctors at British clinics agreeing to terminate foetuses because they were either male or female.
After reviewing the case, the CPS decided it would not be in the public interest to prosecute.
Jenny Hopkins, deputy chief Crown prosecutor for CPS London, said previously that the fact the abortions had not actually taken place influenced the decision not to proceed, saying a relevant factor was that the General Medical Council was already involved and had the power to strike doctors off the register.
In a letter clarifying the detailed reasons behind the decision, Mr Starmer said: "In preparing the more detailed reasons, I have taken the opportunity to assure myself that the decision was properly taken and sound.
"In doing so, I have reconsidered the public interest factors for and against prosecution. I remain of the view that the decision not to prosecute is the right decision on the facts of these cases."
In his letter to Mr Grieve, he said the cases were "by no means clear cut".
The law does not expressly ban gender-specific abortions, he said, but prohibits any abortion carried out without two medical practitioners deciding the health risks of continuing with a pregnancy outweigh those of termination.
He said in this case it would not be possible to prove that either doctor authorised an abortion on gender-specific grounds alone and the only basis would be that they did not carry out a sufficiently robust assessment of the risks to the patient's health to allow them to decide whether the risks in continuing the pregnancy outweighed those of termination.
But he said that was a narrow basis for a prosecution and the evidence was not strong.
"The narrow basis of any potential prosecution and the weakness of the evidence are relevant to the approach taken to the public interest in prosecuting these cases," he said.
"The question in these cases is not whether a prosecution is required in the public interest on the basis that these doctors authorised a gender-specific abortion. That cannot be proved.
"But the very different question of whether a prosecution is required in the public interest on the basis that these doctors failed to carry out a proper health risk assessment on the 'patient' before authorising an abortion."
He said it would be difficult for a jury to assess what an "adequate" assessment by a doctor was, and there was a risk that different juries would reach different decisions on the same facts.
He said both doctors had been referred to the General Medical Council's interim order panel and each had conditions imposed on their registration.
"Having consulted the GMC, it is clear that the council will investigate these cases," he said, adding that although it had no criminal powers, it was arguably more appropriate for a professional disciplinary body to evaluate the proper approach doctors should take in the cases than for a criminal court.
Mr Starmer said ultimately it was not in the public interest to prosecute the doctors, but that did not mean criminal proceedings would not be brought in future cases involving abortions allegedly procured on the grounds of gender.
"The outcome in these cases should not be taken as an indication that criminal proceedings will not be brought where an abortion is procured on gender-specific grounds," he wrote.
"These cases have been considered on their individual facts and merits and there might be powerful reasons for a prosecution in the public interest in such circumstances."
He added: "I appreciate that others may disagree with the decision arrived at in this case, but I am content that the decision not to prosecute on the facts in these cases was the right decision."
Mr Grieve said after discussions with Mr Starmer he was satisfied that he had taken the decision "properly and conscientiously".
He said: "I welcome the reconsideration that the Director of Public Prosecutions has given these cases.
"After the discussions I have now had with the director, and seeing the documents he has published today, I understand that the question in these cases was not whether this was a gender-specific abortion, but whether the doctors made a proper, considered medical judgment.
"This was a difficult decision, and different prosecutors may have come to a different conclusion, but it is not for me to say whether it is the right or wrong decision.
"It is for the DPP to make his decisions independently and based on the individual facts of the matter. However, following our discussions, I am satisfied that the director has taken this decision properly and conscientiously."