宫颈松弛宫颈机能不全较多见的是先天子宫峡部发育不良，子宫畸形并发症之一;少部分是后天产伤的宫颈撕裂后遗症。陈凤林教授指出：宫颈妇检+扩宫试验+动态数字化子宫输卵管造影+阴道四维彩超+阴道镜可以找到原因，具体如下：

Cervical relaxation cervical function is more common in congenital dysplasia of the isthmus, one of complications of uterine malformation; A small part of it is the sequelae of the cervical tear from the acquired injury. Professor Chenfenglin pointed out: Cervical women's examination + palace expansion test + dynamic digital hysterectomy + vaginal four-dimensional color Super + vaginal mirror can find the reason, as follows:

①有宫颈扩张、刮宫等宫颈手术史，急产或产钳助产史。

1 There is a history of cervical surgery such as cervical dilation, shaving, etc., emergency delivery or forceps delivery history.

②较易于受孕，但也容易流产或早产，多有二次以上孕中期自然流产史。流产的特点是，流产前无明显阵发性腹痛，突然胎膜破裂，胎儿很快娩出，胎儿多新鲜，无先天发育异常。

2 It is easier to conceive, but it is also easy to miscarry or premature birth, and there are more than two natural miscarriages in the middle period of pregnancy. The characteristics of miscarriage are that there is no obvious paroxysmal abdominal pain before miscarriage, sudden rupture of the fetal membrane, the fetus is quickly delivered, the fetus is fresh, and there is no congenital abnormal development.

②　扩宫试验(Dilation test)，是诊断宫颈内口松弛的最可靠诊断技术。在非经非孕期，用8号扩宫棒，依次递减，试扩宫口。正常标准：5号扩宫棒不能自由通过宫颈内口。

The Dilation test is the most reliable diagnostic technique for the diagnosis of cervical cavity relaxation. In non-pregnancy, use the No. 8 expansion stick to decrease in order to try to expand the palace. Normal standard: No 5 dilatation rod can not freely pass through the cervix.

④动态数字化子宫碘油造影显示，子宫颈管呈病理性扩张，直径大于6毫米;B超检查显示子宫内口较宽，如果大于19毫米，又有流产史将明确诊断。

4 Dynamic digital uterine iodography showed that the cervical canal was pathologically dilated, with a diameter greater than 6 mm; B-ultrasound examination showed that the uterine cavity is wider, and if it is greater than 19 mm, there is a history of miscarriage that will be clearly diagnosed.

宫颈长度是4cm左右，宫颈宽度是4mm左右，都是4只是单位不同。正常单胎孕妇各不同孕周组间宫颈长度及宫颈管宽度无明显不同，均无宫颈内口开大。

The length of the cervix is about 4cm, and the width of the cervix is about 4mm. It is all 4 but different units. The length of cervix and the width of cervix tube were not significantly different among the different weeks of pregnancy in normal single pregnant women.

阴道B超测量宫颈长度和宫颈宽度，是预测先兆流晚期产和早产宫颈因素的重要手段，统计显示宫颈长度平均为(36±5)mm，宫颈管宽度为(4±1)mm。以宫颈长度≤26mm为界值，预测先兆早产孕妇发生早产的敏感性为100%，特异性为81%，阳性预测值为55%，阴性预测值为100%。

Vaginal B ultrasound measures the length and width of the cervix, which is an important means of predicting the cervical factors of late onset and premature birth. Statistics show that the average length of the cervix is(36 ± 5) mm and the width of the cervix is(4 ± 1) mm. Using the cervical length ≤ 26mm as the boundary value, the sensitivity of preterm preterm preterm preterm preterm preterm preterm was 100 %, the specificity was 81 %, the positive prediction value was 55 %, and the negative prediction value was 100 %.

宫颈过短和过宽，是宫颈机能不全的表现，陈凤林的孕前腹腔镜下宫颈埋箍术，可以有效狙击晚期流产。

The cervix is too short and too wide, is the performance of cervical insufficiency, Chenfenglin's pre-pregnancy laparoscopic cervix implantation, can effectively attack late miscarriage.