Marcel Six, riding for the Metaltek Scott team in an event at Canary Wharf in May, told the tester that his wife was anxious about his children and this was backed up by evidence of text messages and phone calls.
An independent national anti-doping panel ruled however that 26-year-old Six was still guilty of refusing to provide a urine sample for doping control and banned him for 18 months.
The panel said: "Honourable though the athlete's motives may have been, we have no hesitation in finding that his refusal was not based on any compelling justification.
"To be blunt, even if he agreed to race only at the last minute and under pressure, the fact of the matter is that, if he had time to compete in a cycle race, he had to make time to take the test.
"If, as was later the case, he wished to put his family first, then the time to do that was before he agreed to race rather than when he came to be tested."
The panel did reduce the usual two-year ban by six months after deciding Six was able to demonstrate "no significant fault or negligence".