Cold Sores in Pregnancy: How to Manage Them?

July 1, 2024

Pregnancy is a time of great changes for a woman’s body, and it can bring some unexpected challenges.

One of these can be cold sores in pregnancy, a common but potentially bothersome condition that can raise concerns for expectant mothers.

In this article, we’ll explore everything you need to know about cold sores during pregnancy, from causes to treatments, with a focus on the safety of the baby.

What are cold sores?

Cold sores, commonly known as “fever blisters,” are a viral infection caused by the herpes simplex virus (HSV), primarily type 1 (HSV-1).

This virus is extremely common, with an estimated 70% of the world’s population carrying it.

Cold sores typically manifest as a group of small, painful blisters on or around the lips, which can burst, form scabs, and then heal within one to two weeks.

An important characteristic of cold sores is their recurrent nature.

Once the virus enters the body, it remains dormant in the nervous system and can reactivate periodically, causing new episodes of lesions.

This cyclical nature can be particularly frustrating during pregnancy, a time when well-being and comfort are especially important.

What causes cold sores in pregnancy?

During pregnancy, the immune system undergoes natural modifications to protect the growing fetus. These alterations can make the body more susceptible to infections like cold sores or cause the virus to reactivate in women who are already carriers. Several factors can trigger a cold sore outbreak in pregnancy:

  1. Stress: Pregnancy can be an emotionally intense period, and stress is a known trigger for cold sores.
  2. Hormonal changes: The hormonal fluctuations typical of pregnancy can temporarily weaken the immune system.
  3. Fatigue: Tiredness, common in pregnancy, can make the body more vulnerable to infections.
  4. Sun exposure: UV rays can trigger a cold sore outbreak.
  5. Changes in diet: Nutritional deficiencies can affect the body’s ability to fight infections.

It’s important to note that cold sores are not caused by pregnancy itself, but the conditions associated with pregnancy can favor their onset or reactivation.

cold sores in pregnancy

What are the symptoms?

The symptoms of cold sores in pregnancy are generally the same as those that occur at other times in life.

However, some women may experience more frequent or intense episodes during gestation. Typical symptoms include:

  • Tingling or burning in the affected area, often a day or two before the blisters appear
  • Appearance of small fluid-filled blisters, usually clustered
  • Pain and tenderness in the affected area
  • Itching or burning sensation
  • In some cases, mild fever, headache, or swollen lymph nodes

The typical duration of a cold sore episode is 7-14 days, from the onset of the first symptoms to the complete healing of the lesions.

How can I treat it?

While there is no definitive cure for cold sores, there are several ways to manage symptoms and speed up the healing process, even during pregnancy. It’s always advisable to consult your doctor or obstetrician before starting any treatment. Here are some options that can be considered:

  1. Topical antivirals: creams or ointments containing acyclovir or penciclovir may be prescribed to reduce the duration and severity of the episode.
  2. Natural remedies: applying ice or cold compresses can alleviate pain and burning. Some studies suggest that applying honey to the affected area may accelerate healing.
  3. Keep the area clean and dry: this can prevent secondary infections and promote healing.
  4. Avoid triggers: identifying and avoiding triggering factors can reduce the frequency of episodes.
  5. Supplements: taking lysine, an amino acid, can be helpful in preventing and managing cold sore episodes, but it’s important to consult your doctor before taking any supplements during pregnancy.
  6. Rest and balanced nutrition: taking care of yourself, getting adequate rest, and maintaining a balanced diet can help the immune system fight the infection.

It’s crucial to avoid touching or scratching the lesions, as this could cause the virus to spread to other parts of the body or to other people.

Is it dangerous for the baby?

One of the main concerns for expectant mothers is the safety of the baby in case of cold sores. It’s important to distinguish between cold sores (primarily caused by HSV-1) and genital herpes (primarily caused by HSV-2), as the latter can pose more significant risks during childbirth.

In general, cold sores do not pose a direct danger to the fetus during pregnancy. The main risk is the transmission of the virus to the newborn during delivery, but this is extremely rare in the case of cold sores, unless there is an active outbreak at the time of delivery.

To minimize risks:

  • Inform your doctor or midwife if you have a history of cold sores or if you develop symptoms during pregnancy.
  • Practice good hand hygiene, especially during an active outbreak.
  • Avoid touching the lesions and then other parts of your body.
  • If you have an active outbreak close to your due date, discuss precautions to take with your doctor.

It’s reassuring to know that, with the right precautions and awareness, cold sores can be effectively managed during pregnancy without significant risks to the baby.

We at Parentalife are here for you

We are here to accompany you on this journey, providing you with the support, guides and information you need to experience a serene and aware pregnancy.

Remember, you are not alone in this experience, and together we can face any challenge that pregnancy may present.


Leung AKC, Barankin B. Herpes Labialis: An Update. Recent Pat Inflamm Allergy Drug Discov. 2017;11(2):107-113. doi: 10.2174/1872213X11666171003151717. PMID: 28971780.

About the Author

Severino Cirillo

Health, Wellness and Education Expert. With a degree in Community Health, he is the CEO of Informed Parent and is responsible for validating the blog's scientific information and coordinating the editorial team of experts, consisting of gynecologists, midwives, psychotherapists, and others in pregnancy, perinatal, and parenting wellness and health.