Depo Provera is considered a very effective method of birth control. If taken every thirteen weeks, it is estimated to be 99% effective. It does not, however, protect a woman from STDs. Studies indicate that women on Depo have a decreased risk of ovarian cancer, Pelvic Inflammatory Disease, and Endometrial Cancer.
The Orinoco is one of the longest rivers in South America at 2,140 kilometres (1,330 mi). Its drainage basin, sometimes called the Orinoquia, covers 880,000 square kilometres (340,000 sq mi), with 76.3 percent of it in Venezuela and the remainder in Colombia.
The mouth of the Orinoco at the Atlantic Ocean was documented by Columbus on 1 August 1498, during his third voyage. Its source at the Cerro Delgado-Chalbaud, in the Parima range, was not explored by non-indigenous peoples until 1951, 453 years later.he Orinoco delta, and tributaries in the eastern llanos such as the Apure and Meta, were explored in the 16th century by German expeditions under Ambrosius Ehinger and his successors. In 1531 Diego de Ordaz, starting at the principal outlet in the delta, the Boca de Navios, sailed up the river to the Meta.