Semen allergy or seminal plasma hypersensitivity (SPH) presents with a localized vaginal and/or systemic allergic symptoms on exposure to its protein components. Although the true incidence is unclear, its is likely underdiagnosed but an important cause of vaginal swelling and pain during/after intercourse. Systemic allergic reactions can happen that may even require the use of intramuscular epinephrine.
Most symptoms can include, but not limited to, are: hives, swelling, wheezing, shortness of breath, gastrointestinal symptoms or anaphylaxis.
In roughly half the cases, reactions can occur after first time intercourse.
The diagnosis is usually made clinically. Use of a condom prevents reactions, which aids confirming a diagnosis. In addition to a detailed history, skin allergy testing can be performed in a controlled setting. Semen allergy needs to be differentiated with irritant or contact reactions may be incited by vaginal contraceptives, spermicides and lubricants. In addition chronic vaginal candidiasis can be confused with seminal plasma hypersensitivity.
Other differential diagnosis that may present similarly to systemic semen allergy are exercise asthma triggered by sexual intercourse. Food or drug induced anaphylaxis. Latex rubber allergy as well can cause anaphylactic reactions.
Both local and systemic reactions are managed with barrier contraception or graded intravaginal desensitization. Semen allergy has not been shown to cause infertility, but it may make conception challenging due to the discomfort or systemic symptoms caused by unprotected vaginal intercourse.
The date indicates that women who have semen allergy have variable fertility outcomes, although the majority are able to have resolution of symptoms after desensitization and have normal term pregnancies.
Semen allergy is likely more common than recognized and one should always be aware of clinical symptoms that occur during and after intercourse. For patients with a history of anaphylaxis to seminal fluid, an epinephrine auto injector should be prescribed in case of an emergency.