There's an effective, environmentally friendly option for people with periods, and few know about it, research says

(CNN)They have been around since the 1930s, and still, many who menstruate are unaware of the alternative to pads and tampons: the menstrual cup.

They're safe and effective, and can save money and reduce waste and water usage, according to a study published Tuesday in the medical journal The Lancet Public Health, but they aren't well known among women.
"In any impoverished set of circumstances be it in Liverpool, or London, or anywhere in low-middle-income countries, people really struggle -- women and girls really struggle to be able to manage their menstruation," and menstrual cups can be a part of the solution, said Penelope Phillips-Howard, senior author of the study, which analyzed 43 international papers.
    Menstrual cups "are incredibly, you know, good and useful and a product that has been under-recognized and under-valued," Phillips-Howard, a professor of public health epidemiology at the Liverpool School of Tropical Medicine, told CNN. "But beyond that is the bigger picture which is menstrual health, or menstrual hygiene -- it has been so neglected internationally."
      Menstruation is part of life for 1.9 billion girls and women across the globe. When women can't afford adequate menstrual products, something referred to as period poverty, they suffer serious consequences, like missing out on school.
      If women resort to using poor quality sanitary products, it can increase their risk of infections, says the study. Girls in low-middle-income countries report using materials like cloths, cotton wool, tissue paper or disposable pads to manage their periods, the study said.

      How menstrual cups compare

      Menstrual cups are inserted into the vagina when a woman is menstruating, but fluid is collected in a cup, rather than absorbed. Cups should usually be emptied every six hours but can last longer, said Phillips-Howard.
      When it comes to leakage, the report found that menstrual cups are just as effective as more commonly used products, such as pads and tampons. Specifically, four studies that included 293 participants determined that leakage was similar among these three products, with one of the studies reporting significantly less leakage among menstrual cup users when compared to tampon users.
      European, North American and African women and girls didn't experience an increased risk of infection linked to menstrual cup usage, the analysis found.
      However, women reported needing several menstrual cycles to familiarize themselves with the menstrual cup, according to the study.
      The analysis also found that in 13 cases, taking out a menstrual cup was linked with an intrauterine device becoming dislodged. The authors say more research is needed into using an IUD alongside a menstrual cup.
      Because of the limited number of reports on menstrual cup usage, other potential issues could have been missed, according to the authors.
      The paper, partially funded by the UK government, includes results from 43 international studies, that span over 3,300 participants from low-, middle-, and high-income countries. However, some of the studies included in the analysis were