According to an interoffice memorandum from USCIS associate director Michael Aytes, the validity of civil surgeon endorsements on Form I-693 for certain adjustment of status applicants has been extended until January 2007. 

In December of 2004, a policy of the U.S. Citizenship and Immigration Services (CIS)  extended the validity of the civil surgeon endorsement on Form I-693 until the adjustment of status application was judicially settled, only for those applicants where no Class A or Class B medical condition was certified.

Usually, for adjustment of status applicants, the endorsement of a civil surgeon on Form I-693, Medical Examination of Aliens Seeking Adjustment of Status, is valid for one year. Some adjustment of status applications are simultaneously filed with an immigrant visa petition as provided for at 8 CFR 245.2(a)(2) and a number of these applications remain pending longer than a year. Without this policy, the medical exams would need to be resubmitted in these cases.