Cerclage Suture Type for an Insufficient Cervix and its effect on Health outcomes (C-STICH)

INTERVENTION: Participants will be randomly allocated to receive either a monofilament suture or a braided suture to place a cervical cerclage. Apart from the type of thread used, participants will receive identical medical treatment to those not taking part in the study. Information will be collected concerning the risk of losing a baby during pregnancy or within a week of birth, the number of weeks the pregnancy lasted prior to birth, whether the baby was admitted to a Neonatal Unit, the length of stay in the unit and any sign of vaginal or womb infection. CONDITION: Insufficient cervix ; Pregnancy and Childbirth PRIMARY OUTCOME: Pregnancy loss rate (i.e. miscarriage and perinatal mortality, defined as any stillbirth or neonatal death in the first week of life), collected from the medical records at 7 days after delivery INCLUSION CRITERIA: 1. Singleton pregnancy 2. Indication for cervical cerclage (any of the below): 2.1. A history of three or more previous midterm losses or premature births (= 28 weeks) 2.2. Insertion of cervical sutures in previous pregnancies 2.3. A history of midtrimester loss or premature birth with a shortened (= 25 mm) cervix 2.4. Women whom clinicians deem to be at risk of preterm birth either by history or the results of an ultrasound scan and in whom the placement of a cervical cerclage is considered the most appropriate treatment 3. Aged 18 and over SECONDARY OUTCOME: Current secondary outcome measures as of 22/09/2017:; ; Maternal outcomes, collected at discharge from hospital or 7 days, whichever is sooner:; 1. Time from conception to pregnancy end (any reason); 2. Miscarriage and pre viable neonatal death (defined as delivery < 24 weeks); 3. Stillbirth (defined as interuterine death >=24 weeks); 4. Gestation at delivery (in live births >= 24 weeks); 5. Gestational age <28/<32/<37 weeks at delivery (in live births >= 24 weeks); 6. Time from conception to onset of spontaneous vaginal delivery (in live births >= 24 weeks); 7. Sepsis (at any time in pregnancy and until 7 days postnatal); 8. Preterm pre labour rupture of membranes (PPROM); 9. Gestational age at PPROM; 10. Mode of initiation of labour (spontaneous or induced); 11. Mode of delivery (vaginal or operative vaginal or caesarean); 12. Cerclage placement complications (cervical laceration/bleeding from cervix/ruptured membranes/bladder injury); 13. Cerclage removal complications (cervical tears/need for anaesthetic/difficult to remove); 14. Other maternal complications: vaginal bleeding/steroid use/chorioamnionitis/maternal pyrexia of 38°C (intrapartum/postnatal)/systemic infection requiring antibiotics (intrapartum/postnatal)/admission to HDU or ITU (pre/post‐delivery); 15. Serious adverse events; ; Neonatal outcomes, collected from the medical records at 28 days for babies born at term and at the estimated delivery date for babies born preterm:; 1. Early neonatal death (defined as a death within 7 days after delivery); 2. Late neonatal death (defined as a death beyond 7 days and before 28 days after delivery); 3. Birth weight adjusted for gestational age and sex (in live births >= 24 weeks); 4. Small for gestational age and sex (<10th centile; in live births >= 24 weeks); 5. Resuscitation at birth/additional care required (SCBU/NICU/HDU/transitional)/length of stay in additional care; 6. Antibiotics within 72 hours/sepsis (clinically diagnosed/proven); 7. Early neurodevelopmental morbidity (severe abnormality on cranial ultrasound scan); 8. Respiratory support (ventilation/CPAP)/days on respiratory support/supplementary oxygen requirements at 36 weeks post menstrual age ; 9. Necrotising enterocolitis (Bell’s stage 2 or 3); 10. Retinopathy of prematurity requiring laser treatment/disabilities/congenital abnormalities; 11. Serious adverse events; ; Microbiological outcomes, measured at cerclage placement and removal:; Full cultures will be undertaken to identify the complete range of potentially pathogenic bacteria isolated from the suture, and high vaginal area. The likely significance of microorganisms isolated from each clinical sample will be assessed in the context of clinical evidence of infection in the mother and her baby.; ; Previous secondary outcome measures:; ; Maternal:; 1. Gestation at delivery; 2. Mode of initiation of labour; 3. Mode of delivery ; 4. Adverse events: suture‐related cervical tears, chorioamnionitis, maternal pyrexia of 38C, systemic infection requiring antibiotics (infection parameters based on Centre for Disease Control/National Healthcare Safety Network [CDC/NHSN] guidance); ; Neonatal:; 1. Late neonatal death, defined as a death beyond 7 days and before 28 days after delivery; 2. Length of stay in neonatal unit (including level of care); 3. Severe abnormality on cranial ultrasound scan; 4. Oxygen dependency at 36 weeks corrected gestation; 5. Necrotising enterocolitis (Bell’s stage 2 or 3); 6. Retinopathy of prematurity requiring laser treatment; ; Microbiological:; Full cultures will be undertaken to identify the complete range of potentially pathogenic bacteria isolated from the suture and cervix. The likely significance of microorganisms isolated from each clinical sample will be assessed in the context of clinical evidence of infection in the mother and her baby.