If you're dealing with itchy, red skin patches during pregnancy, and wondering whether your hormonal changes are to blame, it is likely, especially as a first-time birth parent..

PUPPP (Pruritic Urticarial Papules and Plaques of Pregnancy) is a skin condition that typically arises in the third trimester. It is also known as polymorphic eruption of pregnancy (PEP) and is the most common type of gestational dermatosis (a skin condition during pregnancy or postpartum).¹ 

The condition was first described by Lawley et al. in 1979, based on the initial clinical findings of urticarial papules and plaques.² The PUPPP rash usually begins as stretch marks around the belly before spreading to the thighs, buttocks, and arms. It never affects the face, palms, or soles. Although these rashes are not harmful to the baby, it can cause pain and discomfort to the birth parent. 

Understanding the hormonal and mechanical factors behind PUPPP not only clarifies why it happens but also opens the door to more effective symptom management. Pregnancy is a period of significant hormonal changes, influenced by two main hormones, estrogen and progesterone. 

Estrogen and progesterone in pregnancy

Estrogen and progesterone are the two most important hormones, in addition to several others, during pregnancy. They play a vital role in the development of the fetus from fertilisation to birth. In a typical pregnancy, the levels of progesterone are responsible for the maintenance of pregnancy and are at their peak in the third trimester.

Estrogen levels can also increase up to 30-fold, whilst progesterone levels can rise as much as forty-fold, in contrast to preconception levels.³ These hormones are crucial for maintaining pregnancy, assisting fetal development, and preparing the body for childbirth. However, these hormones have several additional effects, such as t on the pores and skin, immune system, and connective tissues. These physiological changes in hormones, combined with physical effects like rapid skin stretching, can create a "perfect typhoon" for an inflammatory response like PUPPP.

The role of estrogen in PUPPP rash

 Estrogen exerts several effects that could predispose the skin to PUPPP:

• Increased Vascular Permeability: Estrogen causes vasodilation and increases blood vessel permeability, which lets in immune cells to more without issue migrate into the pores and pores and skin. This influx and histamine launch hallmarks of PUPPP⁴
• Mast Cell Activation: Arises from excessive estrogen which can release histamine into the blood stream.⁵ This sensitivity possibly contributes to the itch experienced by many people with PUPPP
• Compromised Skin Barrier: Estrogen influences lipid production and the integrity of the skin barrier. When combined with stretching skin around the stomach, this makes the skin a greater liability to micro-tears and inflammatory responses⁶
• Collagen Remodeling: Collagen is a protein accountable for skin elasticity, and is regulated with the help of estrogen. In pregnancy, the rapid production of collagen and stretching of skin can cause small tears, which can lead to skin infection⁷

Contribution of progesterone to PUPPP development

Although estrogen is regularly in the spotlight, progesterone performs an equally crucial function in the development of PUPPP:

• Immune Modulation: Progesterone suppresses elements of the maternal immune system to prevent foetal rejection. However, this immune reaction may result in an imbalanced inflammatory cycle within the skin, contributing to the development of rashes like PUPPP⁸
• Fetal Microchimerism: Intriguingly, studies have detected fetal DNA within the pores and skin lesions of people with PUPPP, mainly in those carrying an assigned male at birth (AMAB) fetus. This has led researchers to propose that the maternal immune system may react to these foreign cells, an effect influenced by progesterone’s immune regulation⁹
• Direct Pruritic Effects: Some people report itching after using medication containing progesterone, suggesting that the hormone may directly stimulate itching receptors in susceptible individuals

Beyond hormones: Additional risk factors 

While hormonal modifications lay the foundation for PUPPP, several exclusive elements impact who develops the condition and its severity:

• Skin stretching around the stomach is common if you have had more than one pregnancy or carried a fetus with a high birth weight. This can cause micro tears to the surrounding skin and connective tissues. This bodily pressure is a possible motive for localised inflammation. Notably, about 75–80% of PUPPP cases rise in first-time pregnancies, as the skin is less acquainted to stretching¹⁰ 
• Fetal sex research suggests that about 70% of PUPPP instances involve AMAB fetuses, as a result of of immune reactions in response to AMAB specific antigens or DNA⁹
• Having a genetic predisposition to PUPPP suggests that genetic factors may additionally play a role. Cases of PUPPP in birthing parents or AFAB siblings can also increase a person’s risk¹¹
• Environmental triggers, such as hot, humid climates, tight garb, and exposure to harsh soaps or detergents, may exacerbate itching. These irritants can further weaken the already-compromised skin barrier, intensifying signs and symptoms¹² 

Diagnosis 

Diagnosing PUPPP is commonly predicated based on scientific examination. The rash usually starts and evolves into internal stretch marks close to the belly button and then spreads to the thighs and buttocks. This distribution enables differentiation of PUPPP from other pregnancy-related skin conditions.

Treatment and symptom relief

PUPPP usually resolves in 1 to 2 weeks postpartum, occasionally in hours. However, management during the course of pregnancy is critical for symptom reduction. 

Medical treatments

Topical corticosteroids: Reduce irritation. Oral antihistamines (e.G., cetirizine, diphenhydramine): Help manage itching, in particular at night time.Oral corticosteroids: Occasionally used for excessive times, but only at the same time as different treatments fail. Every medication taken/used in pregnancy should be under the guidance of a Midwife. 

Natural remedies and home care

Colloidal oatmeal baths: bathing with the oat meal reduces infection and soothe the pores and skin. And a Cold compress reduces itching.

Moisturizers and oils: Fragrance-loose emollients, coconut oil, and shea butter can hydrate skin pores.

Dietary tweaks: Some people may discover comfort through decreasing sugar and processed food, whilst consuming omega-3 fatty oil-containing food like chia seeds, flax seeds, and walnuts.

Lifestyle tips

Wear breathable, cotton apparel and hydrate the skin. Avoid wearing clothes that cause friction, and wear loose clothes.

FAQs

Could my rash be something greater than PUPPP?

Possibly. Rashes associated with blisters, in the facial region, or accompanied by a fever may point towards conditions like cholestasis or pemphigoid gestationis. Always seek advice from your doctor.

Is PUPPP dangerous to my baby?

No. PUPPP Rash does not affect a growing baby; it is limited to the birthing parent's skin

Will I develop PUPPP in my subsequent pregnancy?

PUPPP Rash does not occur in some first-time birthing parents, and it rarely recurs in a second pregnancy.

Why does carrying an AMAB baby increase PUPPP risk?

Studies show that about 70% of instances include AMAB fetuses. This may be because the birthing parents' immune system reacts to the AMAB DNA and Proteins

Can food worsen or improve PUPPP?

There isn't always any conclusive evidence; however, following an anti-inflammatory diet may cause a slight improvement in symptoms

Will inducing labor cure PUPPP?

Delivery resolves PUPPP, but induction is rarely required unless symptoms are severe and unmanageable at full term. 

How can I prevent PUPPP in the future?

There’s no assured method; however, keeping the skin moisturised and healthy during pregnancy can reduce the chances.

Summary

PUPPP rash is a complex scenario due to hormonal surges, especially of estrogen and progesterone, combined with skin stretching and immune reactivity. While it poses no risk to the growing baby and normally resolves after delivery, its extreme itching can substantially have an effect on birthing parents. Following tips like hydration and maintaining a proper diet can reduce symptoms. The exact cause and the treatment to avoid PUPPP rash is currently unknown.