Feminising hormones

Hormonal gender affirmation is an important part of many trans and gender diverse people’s lives. Feminising hormones are typically used by trans people who were presumed male at birth (PMAB), including women and non-binary people.

There are several hormones that come under the category of ‘feminising hormones’. The physical and psychological effects that feminising hormones have on the body depend on the type prescribed as well as personal factors including age, body, hormonal history, any existing contraindications, and what a patient wants to take.

TransHub uses the terms masculinising and feminising hormones to describe the effects that hormonal affirmation has on bodies, but not to describe the genders of the people using them. Someone can be a woman who uses feminising hormones, and non-binary people also use feminising hormones, there is no one correct form of hormonal therapy. Being on feminising hormones isn’t the thing that makes someone who they are.

Information and resources for community members seeking gender affirming feminising hormones can be found here.

Estrogen is the primary feminising hormone used by trans women and non-binary people (PMAB). In Australia, estradiol (E2) levels are monitored, rather than estrone (E1).

The Australian Position Statement on the Hormonal Management of Adult Transgender and Gender Diverse Individuals 1, published in the Medical Journal of Australia on 5 August 2019, states that “treatment should be adjusted based on clinical response”. This acknowledges that the clinical management of gender affirming hormones should be individualised, and requires partnership between a treating physician and the trans patient.

This means prescribing estrogen based on how a patient responds to treatment and alongside risk factors, rather than based solely on specifically targeted levels.

Notwithstanding this, the Position Statement1 does recommend targeting estradiol levels of 250–600 pmol/L and total testosterone levels < 2 nmol/L (ie, to the pre-menopausal cis female reference range).

This is controversial across both the trans and medical communities though as these targeted levels are based on recommendations and evidence that are considered Grade 2B i.e weak recommendations on moderate evidence. As described by the Position Statement, “this approach classifies recommendations as strong (1) or weak (2) and evidence quality as high (A), moderate (B), low (C) or very low (D).”

It is recommended that levels are monitored at baseline, every 3-4 months for the first year, and then annually once your patient’s estradiol and testosterone levels are adequate and stable. This includes a full blood count, renal and liver function, blood pressure and lipids, and blood glucose for patients with risk factors.

The Position Statement has been endorsed by AusPATH, the Endocrine Society of Australia (ESA) and the Royal Australasian College of Physicians (RACP).

Estrogen regimens

The following regimen is recommended for full-dose estrogen hormonal therapy.

• Oral estradiol or estradiol valerate 2–6 mg daily, increasing to up to 8mg as needed; or

• Transdermal estradiol patches 100–150 μg/24 hours changed twice weekly

It can be helpful for a patient to start off with oral or transdermal estrogen to determine the ideal levels for their body and preference, and then transition to a subdermal implant as a longer-term solution, if sought. Many people remain on oral or transdermal estrogen for life.

We recommend commencing estrogen and adding an anti-androgen and progesterone shortly thereafter based on clinical response.

Injectible estrogen is not commonly used in Australia.

Subdermal estradiol implants

Another form of estrogen therapy is the subdermal estradiol implants, which are fused crystalline hormone pellets prescribed by a doctor and purchased by the patient from a compounding chemist.

Up until mid-2019, high doses of estradiol implant were common for some patients from Sydney and its surrounds, with varying results for the individual. When seeing a patient who has previously been on a higher than recommended dose, it is important to work with them to find an outcome that balances health risks and the patient’s experiences of, and response to higher doses of estrogen.

Patients who choose this formulation need to be made aware that compounded formulations of estrogen implants are not approved by Australia’s Therapeutic Goods Administration and are therefore not subject to the regulatory conditions of approved pharmaceutical products. Pharmaceutical grade hormone therapies are manufactured by compounding chemists under strict conditions and are required to undergo rigorous testing of content purity and efficacy.

Thank you to our friends at the Cairns Sexual Health Service for creating two fantastic instructional videos all about implants.

Estradiol pellets are avaiable as either 50mg or 100mg pellets, with between 50-100 mg generally considered a preferred dose. Pellets are replaced every 6-24 months, depending on the response of the individual1 The insertion procedure takes approximately 15 minutes, and requires an autoclaved or disposable trocar and cannula, such as those available here.

Your patient’s hormone levels will peak in the first 1-2 months, and then decline slowly until their body has absorbed the implant. Once the implant is inserted, it cannot typically be removed, so it is important to make sure a patient is aware of all possible side effects.

Below is an informed consent form for the insertion of a subdermal estrogen implant.

The role of an anti-androgen, or androgen blocker, is to suppress the production of testosterone and/or block its effects on the body.

The following regimen is recommended 1 for effective testosterone suppression, both are listed on the PBS:

• Spironolactone (100–200 mg daily); or

• Cyproterone acetate (12.5–25 mg daily)

Spironolactone and cyproterone acetate can both cause breast tissue growth.

The use of the anti-androgen bicalutamide is an emerging area of interest in Australia, although this is not listed on the PBS.

While there is limited evidence to support the use of exogenous progestin or progesterone as part of a feminising hormone regimen, some trans women anecdotally report progestogens being an effective and important part of their hormonal care, particularly bioidentical progesterone. Studies on progesterone use in trans women have historically assessed the use of medroxyprogesterone, rather than bioidentical progesterone.

The popular Cyproterone acetate is used as an antiandrogen blocker, it is also a progestin.

Prior J2 makes the case for using bioidentical progesterone to mirror the hormonal health and cycle of people presumed female at birth, due to it being seen as identical to naturally occurring progesterone (ie. progesterone produced in the body) by the body.

Dosage recommendations of oral micronised progesterone can be 100-200 mg daily. The Therapeutic Goods of Australia approved Prometrium, or a compounded version, is typically prescribed.

Side effects of medroxyprogesterone can also include anxiety, and some community members report other negative psychological effects, which can be severe so it is important that your patient monitors their mental health and discusses any changes with you. Additional research has concluded synthetic progestins may be further associated with increased venous thromboembolism risk3, risk factors that don’t appear significant with bioidentical progesterone.

Some trans people prefer to have their progesterone levels be monitored. Progestins cannot be detected by a blood test, but micronised progesterone can be.

Pharmacies charge different prices for oral micronised progesterone, so it’s worth recommending your patient calls around and finds the best price.

For some trans people, being on a lower dose of feminising hormones, or using them occasionally or temporarily is a part of how they seek to hormonally affirm their gender.

It can be difficult to try and implement one feminising change and not another, as once a hormonal threshold is reached, a range of secondary sex characteristics will begin to change.

This is especially the case for breast growth, which may occur even at lower estrogen levels (i.e. 25 pg/ml or 90 pmol/l).

Consultation with a specialist Endocrinologist may be helpful.

The use of hormonal suppression without gender affirming hormonal therapy can lead to adverse health effects, and so is to be undertaken carefully, and with regular oversight.

A Family Court of Australia ruling (Re Kelvin, 20175 overturned an existing law that required all young people and their family to go to Court to commence gender affirming hormones prior to age 18. Treatment can be commenced in Australia with people under 18 only when there is no dispute between parents (or those with parental responsibility), the medical practitioner and the young person themselves with regard to:

• The Gillick competence of an adolescent; or

• A diagnosis of gender dysphoria; or

• Proposed treatment for gender dysphoria

Any dispute requires a mandatory application to the Family Court of Australia as per the judgement of Re. Imogen 20206.

Medical practitioners seeing patients under the age of 18 are unable to initiate puberty blockers or gender affirming hormonal treatment without first ascertaining whether or not a child’s parents or legal guardians consent to the proposed treatment. If there is a dispute about consent or treatment, a doctor should not administer puberty blockers (“Stage 1”), hormones (“Stage 2”) or surgical intervention (“Stage 3”) without court authorisation.

For trans people under 18 whose parents, carers or guardians will not consent to starting hormones, the Family Court must be involved. Unfortunately, in many cases where parents, carers or guardians do not consent, this may result in a trans person simply waiting until they are 18 to access puberty blockers and hormones, or seeking to access them outside of medical care and oversight.

Further assistance is also available at Inner City Legal Centre who offer a NSW-wide free legal service for trans and gender diverse people.

“Ideally, the decision regarding timing of hormone commencement should be individualised to provide best care for the adolescent …The decision should be shared between the clinicians, the adolescent and their family with the values and belief systems of all contributors being respectfully considered.”

Australian Standards of Care and Treatment Guidelines For trans and gender diverse children and adolescents