According to court documents, he was denied treatment after failing to comply with a clinic counselor’s request that he supply information from his current therapist that he was emotionally ready to handle pregnancy and parenting. Mr. Inkster argued that nontransgender patients weren’t asked to do the same. This fall, the Massachusetts Commission Against Discrimination — the state’s civil rights agency — found probable cause for Mr. Inkster. The case will next move on to a conciliation conference, and then to a possible settlement.

Admittedly, the idea of a “pregnant man” makes many people uncomfortable, and photos of Mr. Inkster caressing his bulging belly are startling. The issue is controversial even within the transgender community. “Some people believe if you’re a trans man you shouldn’t be wanting to bear kids,” Jamison Green, the author of “Becoming a Visible Man,” told me. “That’s not something men do. Others think, If you have a body part that does something, why can’t you use it? It’s your body.”

The issue brings up unprecedented questions: Do you use your genetic material to reproduce, and at what time during your transition? Before or after hormone therapy? Before undergoing reassignment surgery that will make you sterile? Should a transgender man like Mr. Inkster keep his breasts so he can nurse later? Is it generally psychologically healthier for someone like him to freeze his eggs and have them inseminated and the embryos transferred to a female partner or surrogate, rather than leave his female reproductive parts intact? How might years of estrogen or testosterone therapy affect eggs and sperm?

These questions matter. One study published last year in the journal Human Reproduction of 90 transgender men in Belgium found that 54 percent wished to have children, and 38 percent would have considered freezing their eggs if the procedure had been available. Other research, published in 2002, by Belgian fertility doctors with Western European transgender women found that 40 percent wanted to have children, and 77 percent felt they should have the option to preserve their sperm before hormone treatment. As fertility technology improves and becomes more widely available, transgender people are realizing that they will have more options in the future.

Jennifer Hastings, a family care physician based in Santa Cruz, Calif., who specializes in transgender health care, says it’s tricky to balance gender identity with family desires. “We have preteens who come in and say, ‘I don’t want to be a mom. I want to be a dad!’ ” she says. “On the other hand, there are youth who know they want to have biological kids from the outset and freeze sperm or eggs after going through puberty.” Since some doctors are concerned that letting transgender teenagers go through puberty in the gender they don’t identify with may be deeply traumatic, they might administer puberty-blocking medications that delay adolescence until the teenagers can begin hormone therapy in their desired gender. But this means the patients may give up the option of having biological children later. “It can be a painful choice for their parents to make,” says Dr. Hastings.