<unk>  is a medical device used to treat an incompetent (or insufficient) cervix (cervix starts to shorten and open too early). Early in the pregnancy a round silicone<unk>  is placed at the opening to the cervix to close it, and then it's removed later in the pregnancy when the risk of a preterm birth has passed. Pregnant women are at risk of giving birth too early when their cervix begin to efface (shorten) and dilate (open). Different treatments have been tried to prevent a late miscarriage or preterm birth. A common treatment is<unk>  cerclage or stitch when a suture is stitched around the opening of the cervix around 12–14 weeks into the pregnancy. A<unk>  is being studied as an alternative to<unk>  cerclage since there are fewer potential complications. More medical studies are needed to decide whether a<unk>  is equal to or the best treatment.
Cervical pessary
Contraceptive implant
Heat-based contraception
Vaginal estrogen
Contraceptive patch
Progesterone vaginal ring
Intrauterine device
Contraceptive sponge