Introduction: Striae in pregnancy are caused by the rupture of collagen and elastic fibers, due to the distension of the skin.The dermal structures that allow the skin to expand – being responsible for the biomechanical properties of the skin such as firmness and elasticity – when ruptured, cause striae. Since pregnancy seems to change these properties in order to facilitate skin distension, there is a correlation between those parameters and the occurrence of striae during pregnancy. Objective: To investigate the correlation between the occurrence of striae and the skin''''''''s capacity to increase its elasticity. Methods: Skin firmness and elasticity was measured with a Cutometer MPA 580® device in order to investigate the occurrence of striae in 60 pregnant women. Results: A positive correlation between increased elasticity and the absence of striae was observed. Conclusions: There is a possible correlation between the occurrence of striae and the skin''''''''s capacity to increase dermal elasticity.

Keywords: PREGNANCY, DERMIS, RELAXIN

Introduction: Stretch marks occur due to the rapid stretching of the skin, which is typical in pregnancy. Several topical treatments to prevent them have been studied.
Objective: To evaluate the effectiveness of a topical formulation (lactic acid and sodium lactate in an emulsion with caprylic and capric acids’ triglycerides) in the prevention of stretch marks.
Methods: Seventy-five pregnant women aged 18-40 were assessed. The treated area was the abdomen and the control area was the inner forearm, with and without the application of the tested product. Softness, hydration, and elasticity – and biophysical measurements for hydration and elasticity – were evaluated.
Results: Of the 52 women who completed the study, 9.6% presented stretch marks in the treated abdominal area. There was a significant improvement in all clinical parameters assessed (p < 0.001). There was a significant improvement – compared the control area – in the instrumental measurements of hydration and elasticity in the abdomen. A significant improvement was also verified in the treated forearm area compared to the untreated forearm area for both parameters evaluated (p = 0.001).
Conclusions: The formulation improved the skin’s elasticity and hydration, reducing the striae incidence more than previously reported in the literature.

Keywords: STRIAE DISTENSAE; PREGNANCY; RELAXIN.