Brief Answer:
Chloasma; Striae gravidarum

Detailed Answer:
Hello. Thanks for writing to us at healthcaremagic

Congratulations to both of you for having the little one in your life. Best wishes! I am Dr. Kakkar. I have gone through your query and I have understood it.

You mention 2 concerns over here: 1) Melasma/Chloasma and 2) Stretch marks.

Your first concern is Melasma. Melasma or chloasma(as it is commonly known as in pregnancy) most commonly presents as hyperpigmentation over the cheek bones/malar area.
Other sites like dorsum of nose, forehead, upper lips etc may also be involved with melasma.
There are only a few well known causes of melasma, specially in females; such as oral contraceptive pills, pregnancy.
Most of other cases have no underlying cause.

Treatment of Chloasma consists of 2 main steps: Sunprotection and Skin lightening creams.

Sunprotection is an essential part in the management of any facial hyperpigmentation including melasma/chloasma.
I would suggest that she uses a broad spectrum sunscreen, throughout the day. It should have both UV A as well as UV B coverage.
Reapply every 2-3 hours ( 8 AM, 11 AM, 2 PM)
A broad spectrum sunscreen that has a minimum spf of 30 or more, would be suitable.
You may find one such sunscreen OTC from a drug store Or you may also get it prescribed from a dermatologist.

At night she may use a skin lightening cream. These creams contain one or more of the following active ingredients in various combinations e.g Tretinoin, Mometasone, Azaleic acid, Hydroquinone, Kojic acid, Arbutin, Glycolic acid, licorice extract, Niacinamide, Vit C etc.

The gold standard combination that is commonly prescribed by dermatologists is a combination of tretinoin, hydroquinone and mometasone (Kligman's formula).

Kligman's formula is the most potent combination for melasma and is usually recommended at the start of therapy; other skin lightening ingredients like kojic acid, glycolic acid, arbutin etc are mainly used for maintenance of improvement.

These are all prescription products and I suggest a visit to a dermatologist in your region. Your dermatologist will give you more details regarding how and when to use and minor side effects like irritation, redness etc that one can expect with these creams

Along with the creams, she may also take a few sessions of chemical peeling from a dermatologist.

Melasma may take time to respond and therefore she has to be patient with the treatment and follow up regularly with a dermatologist.
Your dermatologist might change or modify treatment according to the response.

Your second concern is Stretch marks Or striae gravidarum. Stretch marks form due to rupture of collagen framework of the dermis, as a result of stretching of skin resulting from abdominal distension.
They are an inevitable consequence of pregnancy and weight gain/weight loss. They can be felt as gaps on running the fingers over the skin.
Formation of stretch marks is a type of atrophic scaring because there is loss of tissue/dermal collagen due to rupture of collagen.
Stretch marks are more prominent in the immediate postpartum period when they are red or purple in colour; Over time they turn white and become less prominent.

Though there are lot of OTC creams available to help prevent and decrease the appearance of Stretch marks but none of them works 100%.

She can use a Tretinoin 0.05% cream once daily every night to improve the appearance along with a moisturizer for day time application.
Tretinoin has collagen remodelling properties and helps to reduce the appearance of stretch marks.

Fractional CO 2 Laser and Microneedling are also known to benefit stretch marks by stimulating formation of new collagen, thus filling up the gaps caused by collagen breakdown.

However, none of the method mentioned above is 100 % effective.

You may discuss about these various options from your treating dermatologist and the most suitable method for her.
In most cases of striae gravidarum, counselling and topical treatment is all that the patients opt for.

Regards

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