“You’re so lucky that you’ll never have a period!” Her words stung. My friend meant well. She couldn’t have known the effect her words would have on me, but it reminded me again of my own lack of menstruation as a transgender woman. For me, not getting my period is a painful reminder that my own fertility is not like most other women’s. When people tell me how lucky I am that I don’t have to experience periods, I often think about how lucky they are to be able to bear children.

As a child, when an adult would ask me what I wanted to be when I grew up, I’d always answer with one of those traditional vocations: star athlete, firefighter, police officer, etc. But my secret answer, the one I knew I could never tell another soul, was that I’ve always wanted to be a mommy. I didn’t know why or how at the time — I mean, I was only 10 years old — but I knew it was what I wanted more than anything. I used to lie in bed at night, convincing myself that I really had secret “girl parts” hidden inside me that would soon become apparent when puberty would turn me into the girl I knew myself to be. No such luck came.

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These days, my lack of menstruation is used against me by those who deny my womanhood. Every day a new transphobic person or a TERF (trans-exclusionary radical feminist) will discover my trans advocacy work or my Twitter account and come at me, demanding to know about my genitals. They claim that the only fact determining womanhood is the ability to bear children or to have periods. That ability is obviously something I will never have, but that’s also true of many cisgender women. Are we to exclude all women who struggle with fertility from the definition of woman? No. Many trans women yearn for their own fertility, and being told that we’re not real women because of our lack of menstruation is one of the most hurtful, personal attacks you can wage on us.

Watching my wife go through her second pregnancy was actually a huge trigger for my gender dysphoria. I am lucky to have my own wonderful kids — the best result from my now-ending marriage — because many doctors who prescribe hormone replacement therapy for trans people don’t even discuss options to preserve sperm (or eggs for trans men). So many of us aren’t even aware that there are options, not to mention these preservations generally are not covered by insurance and are cost prohibitive.

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A lack of fertility often also denies trans women romantic possibilities. It doesn’t take long for a trans woman’s natural fertility to end once HRT begins, so their inability to have kids is often cited as a blanket reason for both male and female cis people to exclude them from the dating pool.

So the next time you tell your trans friend that she’s lucky to not ever have to get a period, just be aware that this may be a tough subject for her. Even though it’s uncomfortable, crampy and icky, at the end of the day, menstruation is a sign of fertility, and in that regard, many women will think that maybe you are the lucky one.