Although the exact cause of the condition is not known and varying amongst individuals, there have been theories linking the cause of PUPPP to hormonal alterations, damage to the connective tissue during pregnancy, and autoimmune disorder where the evidence for these theories is currently low.This skin condition occurs mostly in first pregnancies (primigravida), in the third trimester and is more likely with multiple pregnancies (more so with triplets than twins or singletons). Estimated 75% of people with typical PUPPP people have never given birth. Occasionally, this condition may also occur postpartum, but rarely does this ever occur in the first and second trimester.Other than additional associations with hypertension and induction of labour, there are no observed difference in the outcome of the pregnancy for mothers or babies. Dermatological Causes
During pregnancy as the abdominal wall rapid stretching, it is hypothesized that there is an inflammatory reaction that occurs due to the exposure of collagen. This reaction has been seen more frequently in those who are having twins or triplets compared to those with single births. This is hypothesized to be due to increased stretching of the abdominal wall while carrying twins or triplets, causing an earlier onset of PUPPP when compared to those undergoing single births. Hormonal Causes
Throughout pregnancy, there are hormonal changes that occur where it has been hypothesized that these changes may contribute to the onset of PUPPP. Although current research is low on this hypothesis, it has been seen that those who have had multiple gestations can exhibit an increased level of progesterone.
Additionally, a study from Ghazeeri and al. showed that 89% of people who underwent conception through in vitro fertilization were Rh-positive.The timeline of onset for these symptoms has been reported with some variability. However, most people report experiencing symptoms during the third trimester (last few weeks of pregnancy) where 15% of the women who have PUPPP reported that symptoms actually began immediately after delivery of the baby. As mentioned above, the papules and plaques usually first appear on the abdomen (although not on the umbilicus/belly button) and often spread to the legs, chest, underarms, etc. However, lesions on or above the breasts are rare. Thats why the face is usually spared and does not become affected. As a result of these papules and plaques from PUPPP, it causes the skin to be very itchy (pruritic) and immensely affects the patients sleep quality throughout the night. Cause
PUPPP is the most common dermatosis of pregnancy and is the most frequent in pregnant women habitating a male fetus, women who had quick and conspicuous weight gain during a short period, and women who ultimately deliver by a c-section.