We examined the impact of Massachusetts insurance reform on the care of women at six community health centers with abnormal breast and cervical cancer screening to investigate whether stability of insurance coverage was associated with more timely diagnostic resolution. We conducted Cox proportional hazards models to predict time from cancer screening to diagnostic resolution, examining the impact of 1) insurance status at time of screening abnormality, 2) number of insurance switches over a three-year period, and 3) insurance history over a three-year period. We identified 1,165 women with breast and 781 with cervical cancer screening abnormalities. In the breast cohort, Medicaid insurance at baseline, continuous public insurance, and losing insurance predicted delayed resolution. We did not find these effects in the cervical cohort. These data provide evidence that stability of health insurance coverage with insurance reform nationally may improve timely care after abnormal cancer screening in historically underserved women.