Objective: This study examined gender, generational, cultural and
social diversities in timing of sexual debut among Nigerian youths and
determined factors influencing the timings. Methods: We extracted data
of respondents aged 15-24 years from 2012 Nigeria nationally
representative data. The outcome of interest was time at sexual debut
while predictors included residence, marital status, zones, education,
religion, age at first marriage. Data was censored, cox proportional
hazard and generalized gamma models were used to model age at sexual
debut with p=0.05. Results: The median survival time of sexual debut
was 19 years, female youths were twice as likely to begin sexual
activities than their male counterparts, HR=1.99, 1.87-2.11 while
uneducated youths were more than twice likely to have earlier sexual
debut than those with higher education, HR=2.19, 1.95-2.25. Likelihood
of having had sexual debut was about 30% higher among those aged 20-24
years than those aged 15-19 years, HR=1.27, 1.19-1.36. Conclusion:
Females from poor households mostly in rural areas with no education
and who married early in life were more likely to have earlier sexual
debut. Both teenagers and young adults are on different trajectories of
sexual debut but both urgently need sexual and reproductive health
education to delay sexual debut