Medically Reviewed by Amanda Pittelli, NP
Do you want to increase your bottom growth but aren’t sure where to start?
It can sometimes feel like the first rule of bottom growth is “don’t talk about bottom growth.” You can see plenty of “this is my voice after X weeks on T” progressions on social media, but you’re unlikely to find bottom changes popping up on For You Pages. That can leave people walking around with unanswered questions about what changes to expect, when to expect them, and what you can do to encourage the bottom development you want. We’re here to talk about some of the common bottom growth questions and how treatment can contribute to positive body changes during transition.
Disclaimer: In this article, we use anatomical terms to describe certain body parts, including genitalia. We recognize that not everyone uses these words for themselves, and we deeply respect the language you use for your own body.
Join thousands of trans and non-binary folks getting expert gender-affirming care with Plume Clinic.
Genital Anatomy 101
Before getting into how hormone therapy affects the appearance of genitals, it helps to dive into the details of genital anatomy. According to the scientific journal Andrology, every fetus develops a structure called the genital tubercle during the first weeks of gestation. The genital tubercle will eventually form the clitorophallus. The clitorophallus is a structure containing erectile tissue, a glans, and a shaft. The entire structure is densely populated with nerve endings. These structures don’t start to differentiate until after the first 12 weeks of gestation.
How the clitorophallus develops after 12 weeks depends on the hormones present after that. In an androgenic environment, where testosterone is present, the fetus will develop a larger clitorophallus with a contained urethra; this is what we typically think of as a penis. In a less androgenic environment, the fetus will develop a smaller clitorophallus with a separate urethra; this is what we typically think of as a clitoris.
All of which is to say, human beings have a genital structure with a lot of common elements, and elements of that genital structure can change with exposure to hormones, both before and after birth. For example, genital organs change during puberty when hormone levels increase naturally. Gender-affirming hormone therapy (GAHT) can lead to additional changes.
Bottom Changes from Systemic Testosterone
When you start taking testosterone for GAHT, you can expect several physical changes. Body and facial hair growth, skin changes, redistribution of weight, and vocal deepening are some of the most common and visible changes.
Testosterone also drives changes to the genital organs, which remain androgen-sensitive throughout your life. Increasing the quantity of androgenic hormones in the body will trigger the growth of the clitorophallus. The shaft will typically get longer and thicker, it will protrude out more from the pelvis, and it may have more noticeable erectile responses.
There’s no exact way to predict how much bottom growth testosterone will cause. Research on the subject reports that clitorophallus volume increases by four to eight times. Other research shows that 1-2 years of GAHT can lead to enlargement of the clitorophallus of up to 3.83–4.6 cm.
What is clear from the research is that the duration of GAHT matters. The longer you are on testosterone, the more bottom growth you are likely to experience. Growth is gradual, and you may see continued changes throughout the first several years of treatment.
Dosage can also make a difference. Higher doses of testosterone can lead to more dramatic changes all over the body.
While it might be tempting to boost your dose to maximize bottom growth, it’s important to discuss dosing with your doctor. Your health and safety matter, so please be careful when changing treatment plans.
Does Location Matter?
It might seem intuitive to apply topical testosterone or dihydrotestosterone (DHT), which is a more potent topical testosterone cream, directly to the genital area to stimulate bottom growth. There are several reasons to be cautious about doing that.
The testosterone gels commonly prescribed for GAHT have a high alcohol content, so applying them to your genitals could irritate the sensitive skin. Moreover, the way those gels work is that the active hormone is absorbed into the bloodstream through the skin. The changes to your body are caused when there are higher levels of T circulating through your whole bloodstream. The effect isn’t specific to the area where you apply the gel.
DHT has been shown to promote some clitorophallus growth when applied to the genital areas as a treatment for a skin condition called lichens sclerosus. You can talk to your doctor about trying it as an adjunct treatment to regular testosterone gel – if you can get it. DHT has not been approved for use in the United States. You should only use a DHT product if you can get it from a reputable source.
Pump It Up
FTM pumping, sometimes called clitpumping or vacuum stretching, is a technique to temporarily increase the size of your erection. FTM pumps are purpose-designed devices with a cylinder that slides over your genitals attached to a hand pump that utilizes suction to stimulate a larger erection. It can increase blood flow to the area, which may boost the size of erections, increase sensation, and create more intense orgasms.
The effects of pumping are temporary, and your genitals will return to their usual appearance after your erection goes down.
If you want to try pumping, make sure you choose an appropriate device and use plenty of lube to avoid chafing or skin irritation.
Bottom Surgery
Bottom surgery is an option if the changes from GAHT don’t give you the outcome you want. The most commonly performed bottom surgeries are phalloplasty and metoidioplasty.
Phalloplasty involves using skin taken from another part of the body (often the inner arm), which is attached to the genital region, known medically as a neophallus. During surgery, doctors bring the urethra into the neophallus, so you should be able to pee standing up afterward. The neophallus requires a prosthetic implant to become erect. Many people opt to have scrotoplasty and testicular implants at the same time as phalloplasty.
Metoidioplasty involves modifying the existing genitals without grafting any new structures to the area. Surgeons will perform vaginectomy, urethral lengthening, and scrotoplasty, along with adjusting the suspensory ligaments to position the clitorophallus higher on the pelvis. After metoidioplasty, you should be able to pee standing up and get an erection without needing an implant.
Both types of bottom surgery have benefits and risks, as with any procedure. Discuss your goals for surgery with your doctor and make sure you understand the possibilities before making a final decision.
If you’re a Plume Clinic member and have more questions about bottom growth and your own experience with changes during transition, reach out to your Care Team. Many of us are trans ourselves, so we have had similar questions and experiences about bottom growth. Your healthcare provider can answer your questions. If you’re not a Plume Clinic member, learn all about how Plume Clinic works and get started today!
Ready to level up your gender transition?
Get gender-affirming care made by trans people, for trans people.
References:
Grimstad, F., Boskey, E. R., Taghinia, A., Estrada, C. R., & Ganor, O. (2021). The role of androgens in clitorophallus development and possible applications to transgender patients. Andrology, 9(6), 1719–1728. https://doi.org/10.1111/andr.13016
Gooren LJG, Giltay EJ. Review of studies of androgen treatment of female-to-male transsexuals: effects and risks of administration of androgens to females. J Sexual Med. 2008; 5(4): 765-776. https://doi.org/10.1111/j.1743-6109.2007.00646.x
Fisher AD, Castellini G, Ristori J, et al. Cross-sex hormone treatment and psychobiological changes in transsexual persons: two-year follow-up data. J Clin Endocrinol Metab. 2016; 101(11): 4260-4269. https://doi.org/10.1210/jc.2016-1276
Meyer WJ, Webb A, Stuart CA, Finkelstein JW, Lawrence B, Walker PA. Physical and hormonal evaluation of transsexual patients: a longitudinal study. Arch Sex Behav. 1986; 15(2): 121-138. https://doi.org/10.1007/BF01542220
Chi CC, Kirtschig G, Baldo M, Brackenbury F, Lewis F, Wojnarowska F. Topical interventions for genital lichen sclerosus. Cochrane Database of Systematic Reviews 2011, Issue 12. Art. No.: CD008240. DOI: 10.1002/14651858.CD008240.pub2.
New York Toy Collective, “Can FTM Pumping Really Help with Bottom Growth? A Closer Look.”
Cleveland Clinic: “Phalloplasty.“
Johns Hopkins “Metoidioplasty for Gender Affirming Care.”