The 26-year-old was set to move to the Premier League team before transfer deadline day.
However, he has posted on Instagram that he is set to stay at Feyenoord after all.
On Instagram, Bijlow posted: "Dear Feyenoorders, I was on my way to the Premier League.
"After a very special day last Sunday, for which I am very grateful, I was preparing for departure from Feyenoord.
"I didn't find that easy and it wasn't my first choice, but it had to be for the sake of my career.
"The medical examination has shown that Southampton has a different vision than Feyenoord on how to treat an old injury.
"I’m fully fit and this doesn’t bother me, but I respect the vision of Southampton medical staff. This is why I return to Rotterdam, to my club Feyenoord.
"My bond with the city and the club is iron strong. I keep fighting for a place in the goal of Feyenoord and the Dutch national team.
"Feyenoorders, thank you for the support you always give me," Bijlow concluded.