According to pay scale, the top earning Ob Gyn received about $350,000 per year while the lowest income is about $99,520 per year. Based on percentiles, the median salary for 90th percentile of Ob gynecologists has been around $365,708 per year.n average hourly wage for an Ob gynecologist ranges from between $98.31-$168 per hour. The lowest 10 percent of the Ob gynecologists earned about $47.85 per hour while the upper 10 percent of them earned more than $168 per hour. ob gyn salary.