@misc{indiciae715f21c48635,
  title = {Measuring contraceptive efficacy and side effects.},
  author = {I Sivin},
  doi = {10.1002/j.1879-3479.1979.tb00950.x},
  url = {https://pubmed.ncbi.nlm.nih.gov/39809/},
  note = {Source identifier: 39809}
}