Brief Answer:
Detailed information given below.

Detailed Answer:
Hello,

Thanks for letting us know your health concern.

Here is the information you have asked for:

1. The length of the cervix during the non-pregnant state is 4-5 cm. on an average.

2. The length of the cervix decreases progressively as pregnancy advances.

3. During the first trimester, the length of the cervix is around 4.5 cm.

4. During the second trimester, the length of the cervix is around 4 to 3.5 cm.

5. If the length of the cervix at 22 weeks of gestation is less than 3 to 3.5 cm., it is considered short.

6. During the last trimester, the length of the cervix is around 3 cm.

Hope I have answered your query. Please feel free to contact for further clarifications. I will be happy to help.

regards,
Shanti.V.

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Brief Answer:
Chances of premature delivery increase.

Detailed Answer:
Hello,

Thanks for writing back.

If the length of the cervix is 2.5 cm. at 21 weeks, it is considered to be short. The chance of premature delivery is increased in the current scenario. However, if the uterus is not irritable and the length of the cervix is not further lowered, it is possible that the pregnancy may reach full term.

Management comprises of rest, regular monitoring, evaluation of the cervix periodically and contemplate the need for a cervical encirclage. The irritability of the uterus is enhanced when the encirclage is done later than 16 weeks. So, tocolytics are needed.

Use of antenatal steroids to enhance fetal lung function can be suggested in early last trimester.

Hope your query has been answered. Please get back if you need anything else.

regards,
Shanti.V.

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