The Government has failed in a High Court bid to keep secret information it believes could lead to the identification of women who have undergone late abortions.
A judge upheld the Information Tribunal's decision to disclose "sensitive" data from national statistics to the anti-abortion ProLife Alliance.
Lawyers for the Department of Health had argued that the decision, made in October 2009, was legally flawed.
James Eadie QC, for the DoH, said patients could be identified if the data was put together with other information in the public domain, with "awful" consequences for patients.
But Mr Justice Cranston, sitting at London's High Court, ruled there had been no error of law.
The tribunal had been entitled to conclude that the risk of identification was "extremely remote", said the judge.
It was also entitled to conclude that release of the material to a body like ProLife was "proportionate" and necessary to inform the public debate on the controversial subject of abortion.
The judge put a stay on any of the data being released to give the DoH time to appeal to the Court of Appeal.
A Department of Health spokesman said: "The Department will now consider the implications of this judgment and the options available."
The ProLife Alliance (PLA) says it should have full disclosure because it is concerned that the rules on abortion are being flouted to weed out "less than perfect" babies - including those with a cleft palate or club foot - where doctors say such conditions can usually be corrected by surgery.
Abortion on "social" grounds is only legal in the first 24 weeks of pregnancy.
But "Ground E" of the 1967 Abortion Act makes it legal to abort a foetus right up to birth if there is a substantial risk of "serious" physical or mental abnormality.
Until 2002, statistics released on abortions listed in full the number of late terminations for different foetal abnormalities.
The DoH decided in 2003 to suppress the release of figures if the number of late terminations in a category was less than 10 after concerns grew that there was a real risk that women and their doctors in that category could be personally identified because they were so few.
Today, Mr Justice Cranston said the tribunal was entitled to find there was no evidence to back up that concern.
He dismissed the DoH's appeal against the tribunal's decision to uphold the Information Commissioner's decision to release the controversial statistics to the PLA.Reuse content