陈凤林教授指出：宫颈环扎一般选择在四个月以后做，具体做法及效果如下：

Professor Chenfenglin pointed out: The cervix ring is generally selected after four months. The specific practices and effects are as follows:

传统的宫颈环扎在妊娠16-20周左右将宫口用丝线环扎，缺陷是缝扎的只是外口,一旦宫缩发动,不能有效阻止宫颈扩张,且易诱发宫缩而流产，缝扎后还容易引起宫颈管感染，导致胎膜早破流产，成功率不足20%左右。新一代高位环扎安太环有效率达99.9%。

The traditional cervix ring is tied with silk thread around 16-20 weeks of pregnancy. The defect is that the incision is only external. Once the contractions are started, they can not effectively prevent the expansion of the cervix, and they can easily induce contractions and miscarriages. After suture, it is also easy to cause cervix infection. Causes the fetal membrane to break early Miscarriage, the success rate is less than 20 %. The efficiency of the new generation of high ring Za Antai is 99.9 %.