How can trans women preserve their penis size?
Executive summary
Preserving penile size during feminizing hormone therapy is achievable in some cases but rests on a mix of clinical strategies, off-label approaches, and sparse data; most guidance is extrapolated from small studies, cis-male medicine, clinician experience, and community reports rather than robust randomized trials [1] [2]. Proven and commonly discussed tactics include maintaining blood flow with PDE5 inhibitors, targeted topical androgens in limited use, and behavioral maintenance (masturbation/dilation) while recognizing trade‑offs with feminization goals and limited long‑term evidence [1] [3] [4].
1. The core problem: why size can change on feminizing HRT
Estrogen-based feminizing regimens lower circulating testosterone, and that hormonal downshift commonly leads to shrinkage of the penis and testicles—an effect documented in clinical summaries of HRT’s body changes and in patient reports [2] [5]. Clinicians and community writers note the variability: not all transfeminine people experience significant atrophy, but many do, and research into incidence and magnitude in trans populations is limited [2] [1].
2. Medical strategies with the strongest circulation-based rationale
Phosphodiesterase type 5 inhibitors (PDE5i) such as tadalafil (Cialis) or sildenafil (Viagra) are widely reported to restore erectile function and improve blood flow, and a community‑clinical review suggests that low‑dose daily tadalafil (2.5 mg) or on‑demand sildenafil will restore function for the majority of transfeminine patients who lose erections on HRT [1]. Urology sites also list PDE5 inhibitors as useful for maintaining penile blood flow and function during testosterone‑suppressing therapies [3]. These agents act on vascular mechanisms rather than reversing tissue hormone exposure, so they help function and may mitigate some size loss related to disuse.
3. Topical androgens, DHT gels, and localized testosterone—promising but understudied
Some urology sources and clinics describe applying topical testosterone creams or dihydrotestosterone (DHT) gels directly to the penis to preserve tissue without systemic masculinizing effects, and clinicians sometimes weigh these options for individual patients worried about atrophy [3]. However, these practices are not standardized for transfeminine care and carry potential trade‑offs for feminization and systemic hormone targets; the substack review notes that much advice has to be adapted from cis men with hypogonadism because rigorous trials for transfeminine patients are scarce [1].
4. Behavioral and mechanical maintenance: dilation, stimulation, and community practice
Non‑pharmacologic approaches—regular masturbation, sexual activity, vacuum devices, or other means to preserve blood flow and tissue elasticity—are commonly discussed in community guides and patient advice columns as pragmatic ways to slow atrophy, and community voices emphasize experimentation and personal preference in maintenance routines [4] [5]. Clinical literature underscores the role of use‑dependent tissue health in genital anatomy, but formal comparative data on specific behavioral regimens in transfeminine populations are limited [1].
5. Trade‑offs, timing, and the surgical context
Decisions about preserving penile tissue are inseparable from surgical planning: penile tissue is used for standard vaginoplasty techniques like penile skin inversion, and the amount and condition of tissue affect surgical options and outcomes [6]. Conversely, some people pursuing penectomy or vaginoplasty prioritize feminization over preservation; clinicians must discuss lifelong commitments (e.g., dilation after vaginoplasty) and realistic expectations about dimensions based on existing normative data [6] [7].
6. What the evidence gap means in practice and how decisions are made
Guidance largely comes from clinician experience, community reporting, urology summaries, and extrapolated research rather than large controlled trials—explicitly noted in a community review that adapted cis‑male literature was necessary to form regimens—so individualized, informed decision‑making with a knowledgeable endocrinologist and urologist is essential [1] [3]. Sources differ on specifics, and patients and clinicians must weigh the known vascular tools (PDE5 inhibitors), the experimental topical androgen approaches, behavioral maintenance, and surgical goals against the acknowledged scarcity of high‑quality evidence [1] [3].