Change In Moles During Pregnancy: Causes And When To See A Doctor

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Moles are harmless patches or spots on the skin that may be present at birth or develop over time. Women may sometimes notice a change in moles during pregnancy. These changes may be influenced by the physical and hormonal changes in the body. As a result, women may notice new moles or old moles may disappear. Some may even notice that their moles are growing bigger or darker than usual. Fortunately, these changes do not indicate any risk.

However, if you notice some worrying changes in your mole’s color, size, and texture during pregnancy, it is important to consult a doctor (1).

Read this post to know more about the changes moles undergo during pregnancy, the reasons behind it, and the symptoms you should not ignore.

Is It Normal For The Moles To Change During Pregnancy?

During pregnancy, the moles you already have may undergo minor changes. Some, especially those present on the abdomen and breasts, may become larger and darker. These are benign changes that could happen due to the stretching of the skin or fluctuating hormone levels (2) (3).

However, in rare cases, moles that change asymmetrically could become malignant (cancerous) and should be checked by a dermatologist.

What Causes Moles To Develop During Pregnancy?

New moles may develop due to hormonal changes in pregnancy (4). The increasing hormonal levels of estrogen and progesterone stimulate the melanocytes (cells producing melanin pigment) to produce more pigment (5). Moles thereby appear where there is a concentration of pigment-making cells in the skin.

Do Moles Get Itchy When Pregnant?

Moles may get itchy when the nerves of the skin get irritated. The irritation may be from the chemicals that you apply to the skin, peeling of the skin from sunburn, or dry skin (6). In some cases, a mole could turn itchy solely due to the changes it undergoes (stretching skin or hormonal surge).

When Do Moles Get Harmful?

In general, moles have even pigmentation, distinct edges, and a smooth surface. Checking the changing moles and also examining the emerging moles for the warning signs and symptoms is important to determine if they need medical attention. Talk to your doctor or a dermatologist for the right diagnosis if the moles:

  • Have uneven or ragged borders
  • Have uneven color tone, either become darker or have varied colors
  • Form flakes and crusts
  • Are itchy
  • Bleed and cause pain
  • Are raised from the skin surface

These changes could happen over weeks and months. In some cases, these could be signs of melanoma, a type of skin cancer (1).

Is Mole Removal Safe During Pregnancy?

There is limited study on the safety of mole removal in pregnant women. The local anesthetics, such as lidocaine, used to numb the area for a mole excision are relatively safe to use in pregnancy, but in small doses (7). However, higher doses and exposure during the first trimester could have teratogenic effects on the fetus.

Do Pregnancy Moles Go Away After Childbirth?

Pregnancy moles are likely to go away after delivery, unless they are malignant, in which case they warrant medical intervention (2).

What Is Melanoma And How To Look For It During Pregnancy?

Melanoma is a type of skin cancer that develops from pigment-producing cells (melanocytes). It either appears as a new mole or changes an existing mole into a cancerous one. The specific genetic factor that contributes to acquired melanocytic moles remains unknown but developing large numbers of moles may be an autosomal dominant trait. It is also likely to occur from exposure to UV rays from the sun and also tanning beds (8).

The signs and symptoms of melanoma in pregnant women are the same as those in non-pregnant women. To evaluate the changes, you can follow the ABCDE rule. This rule for self-examination of the skin was introduced by a group of dermatologists as ABCD in 1985 and was later expanded to ABCDE in 2004 (9).

  • A is for Asymmetry, which means that half of the mole looks different from the other half in color, shape, or texture.
  • B is for Border irregularity, which implies that the border is irregular or ragged with no defined edges.
  • C is for Color variation, meaning the color is not uniform throughout the mole and has shades of brown, tan, black, red, or even blue and white.
  • D is for Diameter, which suggests that moles greater than six millimeters could be malignant.
  • E is for Evolving; this is also known as ‘the ugly duckling sign,’ where some moles look different from other moles. They change or enlarge with time, and that can be a cause for concern.

If you have a mole that meets one or more of the above criteria, you should consult a doctor immediately.

Melanoma Treatment, And The Implications It May Have On The Growing Baby

Treatment for pregnant melanoma patients is usually the same as it is for anyone else. Also, the treatment depends on the stage of melanoma.

  • For early-stage melanoma, treatment may involve a surgery where the melanoma is removed after the administration of a local anesthetic. Also, a section of healthy skin that surrounds the melanoma is removed, and the surgery is usually considered safe to undergo while pregnant.
  • For advanced-stage melanoma that has spread, chemotherapy and immunotherapy may be the options. Both are not recommended during pregnancy as they pose serious side effects, such as risks of birth defects and spontaneous abortion (2).

Can Melanoma Spread To The Baby?

Melanoma is not likely to spread to the baby. In late-stage cancer, when the internal organs are affected, there might be a risk of cancer spreading to the placenta and the baby. In this case, the placenta needs a thorough examination, and the baby should be under a dermatologist’s supervision (10).

The fluctuations in hormone levels may lead to change in moles during pregnancy. The mole changes brought by the pregnancy-related conditions usually diminish on their own after the delivery. However, if they have taken an irregular shape or if they worry you, it is safe to get them checked by a dermatologist. The medical team would perform a proper diagnosis of the mole to determine its state of normalcy. A malignant mole would be treated promptly.

Alternatively, follow a good skin care routine and avoid sun exposure. Always use dermatologically-approved sunscreens based on your skin type. Visit a dermatologist regularly to identify any skin issues in their early stages.


MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
1. Moles; NHS (2017)
2. Moles and Malignant Melanoma; European Academy of Dermatology and Venereology (2018)
3. Skin Changes During Pregnancy; Health Sciences Library Upstate Medical University (2008)
4. Are moles determined by genetics; U.S. Department of Health & Human Services National Institutes of Health (2017)
5. Gilvan Ferreira Alves et al.; Dermatology and pregnancy; An. Bras. Dermatol (2005)
6. My Mole Itches But Doesn’t Hurt, What Does This Mean; Skin Center of South Miami
7. Ji Min Lee and Teo Jeon Shin; Use of local anesthetics for dental treatment during pregnancy; safety for parturient; Journal of Dental Anesthesia and Pain Medicine (2017)
8. Skin cancer (melanoma); NHS
9. Daniel Jensen and Boni E. Elewski; The ABCDEF Rule: Combining the “ABCDE Rule” and the “Ugly Duckling Sign” in an Effort to Improve Patient Self-Screening Examinations; The Journal of Clinical and Aesthetic Dermatology (2015)
10. Melanoma During Pregnancy: What It Means For You And Your Baby; American Academy of Dermatology Association
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Dr. Irene (Eirini) Orfanoudaki

(PhD, MD)
Dr. Irene (Eirini) Orfanoudaki is a gynecologist-obstetrician, having a private practice in Heraklion, Crete, and collaborating with private health clinic 'MITERA' - Euromeda in Heraklion. With more than two decades of experience as a gynecologist-obstetrician, she specializes in ultrasound, colposcopy, minimal and advance gynecologic surgery, aesthetic gynecology, fertility consulting, menopause consulting, operative obstetrics, high-risk pregnancy, normal deliveries, antenatal, intra-parum, postnatal... more

Rebecca Malachi

Rebecca is a pregnancy writer and editor with a passion for delivering research-based and engaging content in areas of fertility, pregnancy, birth, and post-pregnancy. She has been into health and wellness writing since 2010. She received her graduate degree in Biotechnology and Genetics from Loyola Academy, Osmania University and obtained a certification in ‘Nutrition and Lifestyle in Pregnancy’ from Ludwig... more