SkincareSafety Guide

Skin

Understand your skin type, tone, and what your skin is doing.

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Common skin questions

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Not sure where to start?Use the skin-type guide before choosing routines or ingredients.

Concerns

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Oil and acne

Why oily skin happensThe main drivers behind excess oil.Oily skin and acneHow oil can contribute to breakouts.Can oily skin cause acne?A direct answer to the oil-acne link.

Changes and warning signs

Stress and oily skinHow stress may affect oiliness.Dehydration and oilinessWhy skin can feel oily and dehydrated.Skin cancer signsVisual signs that need professional attention.
Looking for a solution?Start with what oily skin actually needs before adding stronger products.

Ingredients

Understand what ingredients do and whether they fit your skin.

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Explore ingredients

NiacinamideA practical ingredient overview.Vitamin C serumWho can use vitamin C and when to be careful.RetinolHow retinol fits different skin types.

Use safely

Salicylic acidWhere this acne-focused ingredient fits.Niacinamide for all skin typesSuitability across skin types.Ingredient comparisonsUse comparisons to avoid mismatched decisions.
Can my skin use this?Browse compatibility questions before adding a new active.

Routines

Turn skin information into daily decisions.

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Daily basics

Does every skin type need moisturizer?A basic routine decision.Does every skin type need sunscreen?Where SPF fits in daily care.What oily skin needsA simple care direction for oily skin.

Adjust over time

Skin changes with ageWhen your routine may need to change.Seasonal skin changesHow weather affects skin behavior.Korean skincare approachWhat is useful beneath the trend.
Starting from scratch?Begin with moisturizer, sunscreen, and one skin-specific need.

Products

A small selection of skincare products recommended by OuterDerm for simple, effective everyday routines.

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Recommended picks

Daily SunscreenDaily UV protection that has to be wearable enough to stick with.Azelaic AcidA focused 10% azelaic acid when uneven tone or blemish marks are the concern.Gentle CleanserComfortable cleansing when tight or squeaky skin is a warning sign.
Not sure where to start?Browse three carefully selected essentials, then ask on WhatsApp before you order.

Learn

Go deeper into skin science, myths, evidence, and safety.

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Hazardous ingredients

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Product literacy

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Skin science

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Evidence and myths

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Pregnancy & Skin Conditions

Which Trimester Does Melasma Start?

Pregnancy does strange things to skin, and melasma is perhaps the strangest - a cascade of hormonal signals that creates distinctive patches of darker pigment. The timing is surprisingly variable, but there's a pattern worth understanding.

Quick answerMelasma typically begins in the second trimester, usually around 18 to 22 weeks of pregnancy.

Medically reviewed by Obstetrics and dermatology reviewer · Updated Jul 19, 2026 · 7 min read

Pregnant woman with melasma on her cheeks during second trimester
Most Common OnsetSecond trimester (around 20 weeks)
Earliest OnsetFirst trimester (rare)
Latest OnsetThird trimester
Prevalence During Pregnancy15-50% of women
Typical ResolutionPostpartum or after breastfeeding

Key answer

Clear pattern with individual variation

Melasma typically starts in the second trimester, but individual variation means it can appear anytime during pregnancy.

Evidence
Moderate - Clear pattern with individual variation
Best for
Pregnant women concerned about skin changes; Understanding melasma timing
Limitation
Expecting a fixed, universal timeline

See what the evidence shows

Short version

Story in brief

Melasma is remarkably common during pregnancy - affecting somewhere between 15 and 50 percent of pregnant women, depending on which study you read. It's so common, in fact, that it's earned the nickname "the mask of pregnancy" in many cultures, which suggests women have been noticing this phenomenon for a very long time.

The second-trimester onset makes biological sense when you track pregnancy hormone levels. Estrogen rises steadily through the first trimester, but progesterone peaks around the second trimester, and both hormones contribute to melasma. By the time you're around 20 weeks, both are high enough to stimulate melanocytes in susceptible women.

That said, melasma can appear earlier if hormone levels rise quickly or if there's significant UV exposure in the first trimester. Some women also report melasma appearing in the third trimester or even not until after delivery. The variability is part of what makes it both frustrating and completely normal.

Mental model

Visual explanation

Evidence

What the evidence shows

Melasma onset in pregnancy follows hormone levels, not a fixed calendar date. When estrogen and progesterone reach a critical threshold for your individual melanocyte sensitivity, the pigmentation appears - for most, that's the second trimester, but there's wide variation.

Use this section to decide

Does this advice apply to me?

Find the concern or goal closest to yours, then use the fit signal to decide how much weight to give this guide.
Strong fit means the advice is central to that goal.Depends means formula, tolerance, or context matters more.Use caution means do not treat it as the main answer.

  • If your goal is

    Most common onsetUsually relevant
    Fit signal
    Often useful

    Second trimester

  • If your goal is

    Earliest possibleUse caution
    Fit signal
    Limited evidence

    First trimester

  • If your goal is

    Latest possibleUse caution
    Fit signal
    Limited evidence

    Third trimester

  • If your goal is

    Key triggerDepends
    Fit signal
    Possible fit

    Hormones + UV exposure

Explanation

How it works

  1. Hormones rise

    Estrogen and progesterone increase dramatically, particularly in the second trimester.

  2. Melanocytes activate

    Hormones bind to receptors on melanocytes, increasing melanin production.

  3. UV exposure amplifies

    Sunlight stimulates melanocytes further, dramatically accelerating pigmentation changes.

  4. Pigment appears

    The excess melanin becomes visible, creating the characteristic patches of melasma.

Expected results

Results and timeframe

Melasma most commonly starts in the second trimester, around 18 to 22 weeks of pregnancy.

Practical use

How to use it

  1. Start sun protection early

    Sun protection should begin in the first trimester, even before melasma appears.

  2. Track your pigment changes

    Keep an eye on when pigmentation develops; this helps dermatologists understand your specific pattern.

  3. Discuss treatment options with your doctor

    Pregnancy-safe treatments may include topical vitamin C or azelaic acid - ask your obstetrician or dermatologist.

Safety

Side effects and cautions

  • Expecting melasma to appear immediately when pregnancy begins

    Melasma typically takes until the second trimester to appear because hormone levels need to reach a threshold.

  • Assuming your melasma will resolve right after delivery

    Melasma often fades after birth but can persist for months or even years.

  • Thinking timing is the same for everyone

    Melasma onset varies widely - some women never get it, others get it early, and some get it late.

Fit

Who should be careful

  • Expecting a fixed, universal timeline

Helpful context

What else is worth knowing

Who This Affects

What's your pregnancy skin scenario?

When you might expect melasma based on your pregnancy experience.

First pregnancy, no previous melasma

You may develop melasma in the second trimester, or you might escape it entirely — either is normal.

Previous melasma in pregnancy

It's likely to recur in subsequent pregnancies, often at a similar stage.

High UV exposure during pregnancy

Melasma may appear earlier and be more pronounced; rigorous sun protection is essential.

Worth noting

Small details that can change the answer

  • Second Trimester Peak. Melasma most commonly appears in the second trimester when pregnancy hormones reach a critical threshold.
  • Hormonal Lag. The delay between hormonal changes and visible melasma reflects how long it takes for melanocytes to respond and produce noticeable pigmentation.
  • UV Amplification. Sun exposure in early pregnancy can cause melasma to appear earlier than it otherwise would.
  • Individual Variation. Melasma timing varies widely, from the first trimester to the postpartum period.

Hormone levels, not a fixed calendar date, determine when melasma appears.

Some women develop melasma in the first trimester, and some in the third - both are normal.

UV exposure can cause melasma to appear earlier than it otherwise would.

Melasma typically resolves after delivery but can persist in some women.

Definition

What is pregnancy melasma?

Pregnancy melasma, often called chloasma or the mask of pregnancy, is a specific type of melasma that develops during pregnancy. It's triggered by the hormonal changes of pregnancy and typically appears as symmetrical patches of hyperpigmentation on sun-exposed areas of the face. It's a benign condition that resolves after delivery in many women, though it can persist or recur in subsequent pregnancies.

  • Symmetrical pigmentation on cheeks, forehead, nose, and chin
  • Triggered by pregnancy hormones and UV exposure
  • Affects 15-50% of pregnant women
  • Usually resolves postpartum, but can be persistent

Explanation

Why the second trimester?

The second trimester is the sweet spot for melasma onset because of how pregnancy hormones behave. Estrogen and progesterone both rise through the first trimester, but progesterone continues rising after estrogen peaks. By the second trimester, both hormones are at levels that can trigger melanocyte activity. The condition also requires a certain level of melanocyte sensitivity that varies between individuals, which accounts for why some women develop melasma earlier or later - or not at all.

Science

The hormones behind pregnancy melasma

Estrogen and progesterone both contribute to pregnancy melasma, but they affect melanocytes differently. Estrogen increases melanocyte activity and can also affect how melanin is distributed. Progesterone appears to stimulate melanocyte size and melanin production more directly. Both hormones also likely affect other skin cells, such as keratinocytes, which communicate with melanocytes. The relative importance of each hormone varies between individuals and may explain why some women develop melasma earlier or later in pregnancy.

Chloasma
The term sometimes used for melasma during pregnancy, emphasizing its hormonal trigger.
Melanocyte stimulating hormone
A hormone that can increase melanin production and is influenced by pregnancy hormones.
Melanin
The pigment in skin that protects against UV radiation and determines skin color.

Questions

Frequently asked questions

Can melasma start in the first trimester?

Yes, though it's less common. Some women develop melasma very early in pregnancy if hormone levels rise quickly or if there's significant UV exposure.

Does melasma always start in the second trimester?

No, it's most common but not universal. Melasma can start at any time during pregnancy or even not at all.

If I didn't get melasma in my first pregnancy, will I in my second?

Not necessarily. The pregnancy environment can vary significantly, and melasma is influenced by multiple factors, including sun exposure and individual sensitivity, which can change.

Does melasma always go away after pregnancy?

No. While many women see significant improvement or complete resolution postpartum, some women experience persistent melasma.