"It really hasn't come up," Esper told reporters on Thursday when asked whether soldiers had concerns about serving beside openly transgender individuals.
The secretary has already visited soldiers across the U.S., as well as in South Korea, Afghanistan and Europe. Their concerns are likely the quality of food and their pay, he said.
Esper said he met with "six or seven" active-duty transgender soldiers in his first 30 days as secretary and found their perspectives "helpful" as he thinks through the issue.
Next Wednesday, the Pentagon must submit to Trump an implementation plan to address military service by transgender individuals in accordance with an August White House memo. That memo directed the Pentagon to ban transgender individuals from openly serving in or joining the military, but it's unclear what the defense department will recommend to the White House next week.
The new policy is supposed to go into effect on March 23, but there have already been multiple court challenges to the ban.
Esper said he has spoken with mixed-gender infantry and cavalry units whose soldiers emphasized that the issue boiled down to everyone meeting the same standard.
"Everybody wants to be treated with a clear set of standards," Esper said, adding, "At the end of the day, the Army is a standards-based organization."
Beginning on Jan. 1, the Pentagon began allowing transgender individuals to join the military in compliance with a federal court ruling. Entry requirements are based on guidelines issued by former Defense Secretary Ash Carter in 2016 when he lifted the ban on transgender service members. Those guidelines include certifications from a medical provider about an applicant's health.
Last year, defense officials estimated there were about 200 transgender individuals in the military who had self-reported to their services a desire for some form of medical treatment related to their gender identity.
However, the actual number of transgender service members is still unknown, primarily because military personnel records do not currently track transgender individuals.