Background: Acanthosis nigricans and hyperandrogenism have been associ
ated with diabetes mellitus accompanied by insulin resistance. However
, these manifestations have rarely been reported to occur as a result
of the insulin resistance of pregnancy. Case: A 31-year-old woman with
diabetes mellitus exhibited severe insulin resistance during pregnanc
y. At 32 weeks, daily administration of 500 U insulin was required to
maintain glycemic control. Skin lesions typical of acanthosis nigrican
s appeared, and free testosterone levels were elevated (10.3 pg/mL). T
hese manifestations resolved after delivery. Conclusion: This case may
demonstrate a correlation between reversible gestational insulin resi
stance and acanthosis nigricans.