Tuesday, April 7, 2015

Can some contraceptives cause abnormal bleeding?

Scimex: An international study has looked at the process that leads to the abnormal uterine bleeding, commonly experienced by women taking long-acting progestin-only contraceptives (LAPCs), which in Australia and New Zealand include products such as the Depo Provera injection, Implanon implant, and Mirena intrauterine device. The researchers found that LAPCs actually cause changes to the cells that line the uterus, which they say could lead to abnormal uterine bleeding patterns.
A study suggests that contraceptive-linked abnormal uterine bleeding (AUB) may be caused by impaired development of blood vessel cells in the uterine lining. While AUB has been associated with the use of long-acting progestin-only contraceptives (LAPCs), the mechanisms that underlie AUB are unknown. Umit A. Kayisli and colleagues examined the differentiation, proliferation, and migration of human and guinea pig endometrial vascular smooth muscle cells (VSMCs) to uncover potential causal links between LAPCs and AUB. The authors observed the effects of progestins used in LAPCs on VSMCs in vitro and in guinea pigs as well as in six reproductive-age women before and after use of Depo-Provera. Human and guinea pig VSMCs displayed reduced proliferation and migration, and the endometrial vessels of women receiving Depo-Provera treatment contained thin-walled, hyperdilated microvessels. Treatment of cultured VSMCs with chemokine ligand 2, a signaling protein, reversed the inhibitory effect of progestin on the cells. According to the authors, the results suggest that LAPCs inhibit the proliferation and migration of VSMCs, thereby impairing the integrity of endometrial vasculature and leading to AUB. However, the effect might be reversed by administering chemokine ligand 2, according to the authors.