What is a sperm allergy and how do I know whether I have one?

Can you be allergic to sperm?

Yes, you can but it is rare (Schacher et al 2024). It may sometimes be mistaken for a more common condition, such as thrush (Lavery et al 2020, Schacher et al 2024).

It's not the sperm itself that causes the problem, but proteins in the semen (Lavery et al 2020, Schacher et al 2024). Sperm allergy is also known as semen allergy or seminal plasma hypersensitivity (SPH).

What are the symptoms of sperm allergy?

If you've developed an allergy to your partner's semen, during or after unprotected sex (without a condom) you may have the following symptoms in and around your vagina:

• pain
• burning
• swelling
• itching

(Lavery et al 2020)These symptoms can be triggered by skin contact with semen, as well as sex and can start immediately after contact with semen (Lavery et al 2020).

If you have a more widespread (systemic) allergic reaction to semen, you may have the following symptoms:

• itchy skin or a raised rash (urticaria)
• tightness in your chest
• wheezing
• diarrhoea
• dizziness

(Lavery et al 2020)

If you have these more widespread symptoms, you may react within minutes or up to an hour after contact (Lavery et al 2020). You'll usually feel better within about 24 hours, although some people find their symptoms linger on for days or weeks (Lavery et al 2020). However, sperm allergy is rare. An itchy feeling after sex is more likely to be caused by the fungal infection thrush. Make an appointment to see your GP if you’re experiencing any itching or other symptoms so they can rule out thrush and other possible infections such as chlamydia.

Can semen allergy cause an anaphylactic shock?

Yes, in extreme cases, semen allergy can cause life-threatening anaphylaxis. Although this is very rare, you need to take it seriously if you're having symptoms of a severe allergic reaction. Call 999 if:

• your lips, mouth, throat or tongue swell up suddenly
• you're struggling to breathe – you may be very wheezy or feel like you're choking or gasping for air
• your throat feels tight or you're having trouble swallowing
• your skin, tongue or lips turn blue, grey or pale (on black or brown skin this may be easier to see on your palms or the soles of your feet)
• you suddenly become very confused, drowsy or dizzy
• you faint or cannot be woken up

(NHS 2022) If you have these signs of a severe allergic reaction, you may need urgent treatment in hospital.

How can I be sure I'm allergic to semen?

One way to tell if it’s a sperm allergy or something else, is to have sex using a condom (Lavery et al 2020). If you still experience symptoms after sex, it’s very unlikely that a sperm allergy is the cause. Some people are allergic to latex, so use a latex-free condom for this test, to be on the safe side (Lavery et al 2020).

You can also see your GP for help working out what is happening, especially if your symptoms are starting to worry you or it is starting to put a strain on your relationship. They can take your medical history and do some tests to rule out infections, such as thrush or herpes. Your GP may be able to arrange some allergy tests or refer you to an allergy specialist to have them done. Tests for semen allergy may include:

• skin prick or patch tests
• blood tests

(Lavery et al 2020, Schacher et al 2024)

What causes sperm allergy?

Experts don't really know why some women are allergic to semen. You may be more vulnerable to a widespread allergic reaction if you are generally prone to allergies. You may have other allergic conditions such as eczema, asthma, hayfever or food allergies (Lavery et al 2020).

Sperm allergy may happen for the first time when you have sex with a new partner, or even suddenly during a long-term relationship (Lavery et al 2020).

What is the treatment for sperm allergy?

First of all, if your semen allergy causes anaphylaxis, then the hospital where you are treated should prescribe an adrenaline auto-injector (EpiPen, Jext or Emerade are the brands available in the UK). You should then be referred on to an allergy clinic and get more prescriptions for adrenaline from your GP (Lavery et al 2020, NHS 2022).

If you are not trying to get pregnant, the easiest way to prevent semen allergy reactions is to avoid contact with semen by using a non-latex condom for sex (Lavery et al 2020).

Can I get pregnant if I'm allergic to semen?

Yes, you can, although you may need help and support (Lavery et al 2020, Schacher et al 2024). Understandably, if you have a semen allergy it can cause a lot of strain and anxiety around having sex and getting pregnant (Lavery et al 2020). Particularly if your symptoms are very painful or uncomfortable or if contact with semen makes you feel very unwell.

You could try taking antihistamines before sex, if your symptoms are mild (Lavery et al 2020). Otherwise, it's best to talk to your GP about your options. They may refer you to an allergy specialist who can offer you treatment to desensitise your body to semen. This may need to be private treatment, as the availability of desensitisation treatment on the NHS is very patchy. This can work very well with widespread allergic reactions to semen (Lavery et al 2020). However, it may not ease your symptoms completely if you have localised vaginal symptoms (Lavery et al 2020).

Another option is to use assisted conception. A fertility specialist may offer you intrauterine insemination (IUI) using washed sperm. You have a much lower chance of having an allergic reaction if the sperm has been thoroughly washed before the procedure (Lavery et al 2020).

Other fertility treatments that can help include in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI).

Can men be allergic to sperm?

In rare cases, men can suffer from symptoms of semen allergy, too. This may be felt as flu-like symptoms, such as fatigue, headache and fever, after orgasm (GARD 2024). If you or your partner suffer from this, speak to your GP, who may refer you to a specialist for tests and treatment.

You might also like:

• Not sure if it’s a sperm allergy? Read about thrush and fertility.
• Learn more about assisted conception treatments.
• Discover how to prepare your body for pregnancy.