A physician must always be informed of any medications the patient is taking, even if they are unrelated to gynecologic problems. There have been some reports of strokes, unexpected pressure in the brain, and clotting abnormalities in women using implants, but there is no evidence that Norplant was the cause of these unusual events. Side Effects of Progestins Because progestins are found in many birth control devices, their side effects are listed separately. Most of the adverse effects of progestins are due to the fact that they act like male hormones. Certain progestins, such as norgestimate and desogestrel, have less masculinizing effects than others, although they may pose a higher risk for blood clots than older progestins, such as levonorgestrel .
Progestin thins the lining of the uterus and prevents it from shedding.
Focus on Implanon. Doctor's Guide, September 13, 2000. Timing of onset of contraceptive effectiveness in Norplant implant users. Effect on the ovarian function in the first cycle of use. The reports are distinguished from other information sources available to patients and health care consumers by their quality, detail of information, and currency.