First off, I want to say I really like PMMA, specifically Bellafill, for its duration and for how naturally it feels once healed. It’s one of the most natural-feeling fillers available.
That said, what you’re describing isn’t uncommon and doesn’t necessarily mean anything went wrong. Early swelling gives the illusion of a major increase, but once that fluid resolves, the penis can look close to baseline until collagen production begins — typically starting around week 3 and continuing for several months.
When people feel their result “failed,” it’s often due to under-correction. If only a small number of syringes were used (for example, 5 cc or even 10-15 in someone with significant starting length), the initial post-swelling size will appear to vanish simply because the actual filler volume was modest. Bellafill also yields less immediate bulk per cc than a hyaluronic acid filler like Voluma, though the trade-off is permanence.
Some patients combine HA and PMMA — the HA provides instant fullness while the PMMA gradually builds long-term collagen. Most of the time, if you have a conservative first round is just the starting point, and additional sessions are where the true, lasting gains appear.
PMMA Before and After Photos
Dr. S