By early December 1961 Thalidomide was almost completely withdrawn from markets in West-Germany, Australia and the UK – unlike in Canada. Instead of urgently removing the drug from sale there as well, Richardson-Merrell and Frank W. Horner Ltd. (both drug companies had been given permission to sell Thalidomide in Canada by the Canadian Food and Drug Directorate) sent letters to doctors across the country, mitigating the news they had just received from Germany. Doctors were simply asked not to prescribe the drug to pregnant women any more. Not much else happened for another four months, meaning the drug was still in circulation and still taken by pregnant mothers. In fact, there are at least 30 Canadian Thalidomiders whose mothers took the drug after it was taken off the market in Germany in November 1961.
Source: Michael Magazanik: Silent Shock. The Men behind the Thalidomide Scandal and an Australian Family’s Long Road to Justice. Melbourne 2015, p. 164.