For some folks, this may not be a consideration, but for those exploring or interested in family planning visions, read on.
Hormone replacement therapy (HRT) is a big, exciting step for anyone who chooses it as a tool to feel at home in their body. For those who take estrogen, there are a wide range of physical effects from breast growth to skin softening and so on. Another impact is on the reproductive system and fertility.
Estrogen affects the physicality of the assigned male reproductive system (read: testes). Long-term estrogen usage leads to significantly reduced testicular volume, which impacts the goods inside (read: sperm). Sperm maturation and motility are impacted, as well as the ability to get an erection. Maintaining an erection and ejaculation is also affected by taking estrogen and/or Testosterone-blockers. All that is to say: the mechanics of releasing the ejaculation and the sperm count required to create a pregnancy may be impacted when on estrogen.
Pregnancy IS still a possibility during the type of sex where sperm from one person enters the vagina/front hole of their partner and meets their egg. Just because someone is on estrogen or T-blockers doesn’t mean they are not producing any sperm. (Just as if someone with ovaries is on Testosterone, it doesn’t mean they aren’t ovulating.)
If someone is trying to create a pregnancy, but stopping hormones is NOT an option for them, there are still options. There is also, of course, the option of having sex with the goal of a pregnancy, even without coming off of hormones. If you choose this, conducting a semen analysis to assess current fertility levels while on hormones is a good idea. And there is also the option to use stored sperm for alternative fertility methods like intracytoplasmic sperm injection (ICSI) to fertilize an egg, before implanting the embryo in a uterus. Alternatively, there is the option to place the stored sperm directly into the uterus of someone carrying the pregnancy, called intrauterine insemination.
All of this is also to say: estrogen does not act as birth control. If someone wants to continue having the type of sex that could result in pregnancy without risk of impregnating someone, they should employ birth control options for themselves and/or their partner(s).
Some folx will choose to store their sperm for a future pregnancy before beginning estrogen both because of the impact of estrogen on fertility, as well as the simple fact that, for all genders, fertility is at its peak at younger ages.
It’s ideal to store sperm early on, and if possible, before starting HRT. Local fertility clinics or sperm banks are options for storage, and others use at-home storage kits. Prior to storing sperm, it's a good idea to get a semen analysis for sperm count (how many), motility (how many can move), and morphology (how many are a normal shape) to make sure sperm is fertile enough to store. If someone has trouble with ejaculation, there are surgical options for sperm extraction.
Depending on the length of time someone has been on hormones, as well as other factors that affect individual fertility (age, health conditions, etc), they may not be fertile enough to create a pregnancy while still taking estrogen. In that case, there is the option to go off of hormones for a few months so sperm production can recover somewhat and reach a higher level of fertility.
There is much left to be desired in the sex education and family planning world for queer, transgender, and nonbinary folx on HRT. For FOLX members with further questions about estrogen and fertility options, consider scheduling an appointment with a provider. For anyone who isn't a FOLX member, drop us a line at firstname.lastname@example.org and we'll do our best to help you out.