Methods: Skin-prick testing.
Results: 39 yo F with cyclic abdominal and facial rashes at the peak of progesterone surges with positive progesterone skin-prick testing, presented with vulvar irritation and anterior truncal rash, similar to her progesterone-induced rash, following contact with semen. She recently re-initiated unprotected intercourse after 2 years of abstinence. HSV and urine testing were unremarkable. She denied asthma or atopy. Symptoms were absent with condom use and unprotected intercourse mid-cycle, but present with unprotected intercourse the week prior to menses.
Conclusions: This is a novel case of cyclic seminal plasma sensitivity with concomitant progesterone sensitivity. This presentation suggests cross reactivity between progesterone and seminal plasma allergens, such as testosterone, which shares similar chemical/structural properties with progesterone and is found in semen. Further studies such a skin testing to seminal plasma proteins are needed to prove seminal sensitivity and identify cross-reactive allergens. Routine screening for symptoms of progesterone sensitivity may be reasonable in patients with seminal sensitivity.