borderline significantp = 0.071
The three groups of paternal ages < 30, 30-<35 and ≥ 35 years showed borderline significant differences in the OR of implantation failure between the two groups, smoking and never-smoking, in the paternal age group ≥ 35 years (ROR 1.75, p = 0.071), following a non-significant increased ROR at the paternal age of 30-<35 years (1.17, p = 0.277).