Cervical Insufficiency & Cerclage- A Reason For Mid Term Pregnancy Loss & It’s Treatment
-Cervix is the lower part of the uterus which opens in the vagina.
-During the entire duration of 9 months of normal pregnancy it stays closed and when labour pains start it opens up and dilates and let the baby be born.
-You can say say that it is like a closed door .When fetus in uterus is increasing in size and weight , it is very important that this door stays closed else, baby will be born prematurely.
Cervical insufficiency is a distinct clinical entity
It is characterized by painless cervical dilatation in second trimester of pregnancy ( 13-28 weeks of pregnancy ). It is also associated with decreased length of cervix- Short Cervix
It results in prolapse (bulging out ) and ballooning of membranes around fetus (Amniotic Sac/Amniotic Membranes-these membranes make a sac around fetus and protect the pregnancy ) into vagina and ultimately expulsion of an immature fetus.
Unless effectively treated this sequence of events may get repeated in subsequent pregnancies.
1) Ultrasonography- Inadequate Cervical length is an indicator along with funneling of cervix which is ballooning of membranes into the dilated internal os but with a closed external os.
2) Clinical internal examination by the Gynaecologist
Previous cervical trauma caused by surgeries like
-D & C- Dilatation & Curettage
-Conization- Removal of a diseased tissue of cervix in manner of a cone
-Cauterization- Electric current application to cervical tissue for purpose burning the diseased tissue and stimulate generation of new and healthy tissue
-Amputation- Removal of protruding part of cervix
-Abnormal cervical development
Precautions before treatment of Cervical Incompetence
– Ultrasound is done to check for fetal well being.
-Sexual intercourse is prohibited one week before and after the surgery.
Contraindications to treatment
-Bleeding from vagina
-Uterine contractions and pain
-Rupture of bag of membranes- leaking of fluid
Treatment of Cervical Incompetence
Classic Cervical Incompetence is treated surgically with ‘Cerclage ‘ operation which reinforces a weak cervix by a purse string suture ( Stitching of mouth of uterus). The suture material used is strong, thick and non absorbent. These sutures will now provide strength to the cervix to stay closed even though the weight of the fetus will keep on increasing.
This procedure is done as prophylaxis ( prevention ).
At times ‘Rescue Cerclage’ is needed as patient presents with symptoms in emergency.
This suture is removed at a selected date when the pregnancy has attained a mature state and the newborn will be healthy.
At times the suture needs to be removed in emergency if the patient goes in labour prematurely.
When to do the Cervical Cerclage Surgery
-Most medical text books recommend surgery at 12-14 weeks of gestation- A sonography at this stage will rule out majority of congenital malformations ( Birth Defects )
-If there is previous loss of pregnancy, surgery should be done a couple of weeks prior to gestation age( pregnancy duration) at which the loss occurred.
– If pregnancy is at a later stage- there is risk that Cervical Cerclage operation might induce contractions of the uterus and in turn will lead to loss of pregnancy .
Success of Cerclage surgery
Many medical studies have been conducted and it is found out that the success of this surgery is unpredictable.
Many Gynaecologists will opt for alternative method of managing patients with cervical incompetence- like bed rest, abstinence, Progesterone hormone support , Tocolytics ( Uterine relaxants medicines)
After a thorough counselling of patient and relatives, a treatment option is chosen for that particular woman.The pros and cons of doing the surgery vs conservative approach is discussed.
Name of Cervical Cerclage Surgery
McDonald Cervical Cerclage ( Most commonly done surgery )
Procedure-How it is done
After giving anaesthesia , patient is put in lithotomy position ( Legs spread and supported, patients buttocks reaching the edge of the operation table )
It is a trans vaginal procedure
With the help of instruments ( Sim’s Speculum)- Cervix is exposed.
With the help of non traumatic instruments ( Sponge holder/ Ring forceps )- Cervix is held
Non-Traumatic needle ( Round body ) is used along with non absorbent , thick suture ( Thread ) and purse string sutures are placed as high as possible on Cervix.
Rupture of membranes
To summarize- Cervical Incompetence is one of the causes of recurrent pregnancy loss. Timely treatment may reduce further losses. It is very important that Gynaecologist and patient have a detailed conversation . Then only treatment protocol should be decided.