Deciding to start a family is deeply personal and complicated for women who have to take into account what's best for themselves as well as their families. But millions of women across the world lack access to the birth control that allows pregnancy to be a decision at all. In an opinion essay posted to National Geographic , Melinda Gates — who memorably pledged to provide family planning to 120 million women across the globe back in 2012 — opened up about why birth control is so important. "The decision about whether and when to get pregnant was a decision that Bill and I made based on what was right for me and what was right for our family—and that’s something I feel lucky about," she wrote about herself and her husband. More than 225 million women worldwide don't have that same option, Gates explains, simply because they cannot access the contraception necessary to plan pregnancies that are best for them and their families. In 2012 Gates co-chaired the Family Planning 2020 summit, which pledged to get 120 million women access to birth control by 2020. While Gates and other world leaders present at the summit have been able to provide family planning services for 24 million women so far, they still have so much work to do to reach their goal. "Unless we begin making up for lost time, we will miss this chance to make this a turning point for women around the world," Gates wrote. Read her full essay on National Geographic