Table 2.

Accelerated release conditions used in the in vitro release testing of LNG-IUSs with different drug loading.

No.	Accelerated release conditions	Sampling Plan
1	20% v/v THF, 80% v/v pH 7.4 PBS with 0.25% w/v SDS at 45 °C; 100 mL	1 mL samples were withdrawn at 2, 4, 6, 8 and 24 h eveiy day and fresh media was replenished after sampling; following sampling at 24 h, the media were drained and replenished with fresh media.
2	20% v/v TBA, 80% v/v pH 7.4 PBS with 0.25% w/v SDS at 45° C; 100 mL	1 mL samples were withdrawn oil days (1, 2, 3 and 4) in the first week, and replenished with fresh media. Following the day 7 sampling, all the media in the bottles were drained and replenished with fresh media. Thereafter, samples were withdrawn eveiy subsequent fourth and seventh day. The media were drained and replenished following sampling.
3	20% v/v TBA, 80% v/v pH 7.4 PBS with 0.25% w/v SDS at 65° C; 100 mL	Same as Condition 2
4	70% v/v TBA, 30% v/v water at 45 °C; 250 ml,	1 mL samples were withdrawn eveiyday up to 10 days and replenished with fresh media. Following the day 10 sampling, all the release media were drained and replenished. Thereafter, samples were withdrawn eveiy subsequent fourth and seventh day. The media were drained and replenished following sampling.
5	70% v/v TBA, 30% v/v water at 65 °C; 250 ml.	1 mL samples were withdrawn eveiyday up to 10 days and replenished with fresh media. Following the day 10 sampling, all the release media were drained and replenished. Thereafter, samples were withdrawn thrice a week (on alternate weekdays). The media were drained and replenished following sampling.
6	45% v/v TBA, 55% v/v water at 65 °C; 200 mL	1 mL samples were withdrawn eveiyday up to 10 days and replenished with fresh media. Following the day 10 sampling, all the release media were drained and replenished. Thereafter, samples were withdrawn thrice a week (on alternate weekdays). The media were drained and replenished following sampling on the seventh day of eveiy other week.