The use of levonorgestrel in contraception is well-established. Its effects are mediated primarily through local progestogenic activity in the uterine cavity. The high levonorgestrel concentration in the endometrium downregulates endometrial oestrogen and progesterone receptors, making the endometrium relatively insensitive to circulating estradiol and preventing proliferation. Thickening of the cervical mucus inhibits the passage of sperm through the cervical canal while the local milieu of the uterus and fallopian tubes inhibits sperm mobility and function, thereby preventing fertilisation.1
The efficacy of the levonorgestrel 13.5mg IUS (T-frame size 28mm x 30mm) was assessed in an open-label single-blind phase III study involving 1,432 parous and nulliparous women aged 18 to 35 years.2
The one-year and three-year Pearl Indices were 0.41 (95% CI 0.13-0.96) and 0.33 (95% CI 0.16-0.60), respectively, with an estimated cumulative failure rate over three years of 0.9%.2
Placement of the IUS was rated by investigators as easy in 90% of women and very difficult in 1% of women. The device was generally well tolerated with treatment-related serious adverse events reported by 0.6% of women.2
Spotting may occur during the first few months of using Jaydess. Thereafter, the strong suppression of the endometrium results in a reduced duration and volume of menstrual bleeding.1
- Jaydess Summary of Product Characteristics, April 2014.
- Nelson A et al. Obstet Gynecol 2013; 122: 1205-13.
Further information: Bayer