title: Prevalence and risk factors of inadequate cervical dilation following laminaria insertion in second-trimester abortion--case control study.
abstract: OBJECTIVE
  The objective was to explore the prevalence of and risk factors for inadequate cervical dilation following insertion of a single set of laminaria in women scheduled for dilation & evacuation (D&E) at 14-24 weeks' gestation.
  
  
  METHODS
  We retrospectively reviewed all cases of women who underwent pregnancy termination by D&E at 14-24 weeks' gestation between January 2003 and December 2013. All cases in which the surgical procedure was cancelled due to failure to achieve adequate cervical dilation after a single set of laminaria inadequate cervical dilation were included. The control group was women who underwent D&E following adequate cervical dilation after a single set of laminaria, and were matched according to gestational week in a ratio of 1:3.
  
  
  RESULTS
  The overall dilation failure rate was 3.2%, with 4.0% among the induced-abortion patients and 1.5% among the patients with fetal demise (p=.002). Patients who had inadequate cervical dilation had lower rates of gravidity (p=.002) and previous spontaneous vaginal delivery (p<.001), along with higher rates of primigravidity, nulliparity (p<.001), previous cesarean section/s (p=.041), previous abdominal surgeries (p=.001) and previous cervical procedures (p=.003), compared to controls. A multivariable logistic regression analysis revealed two risk factors for inadequate cervical dilation following laminaria insertion, namely, previous cesarean section (p=.002) and previous cervical procedure (p<.001), whereas increased gravidity was found to protect against inadequate cervical dilation (p=.002).
  
  
  CONCLUSIONS
  Previous cesarean section/s, cervical procedures and primigravidity were found to be risk factors for failure to achieve adequate cervical dilation after a single set of laminaria. Women who are scheduled for D&E, and in whom one of these risk factors exists, might benefit from additional interventions to achieve better cervical preparation.
authors.affiliation: Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin, Israel, affiliated with the Sackler School of Medicine, Tel-Aviv University. Electronic address: idorit@netvision.net.il.
authors.forename: Ido
authors.initials: I
authors.lastname: Ben-Ami
authors.affiliation: Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin, Israel, affiliated with the Sackler School of Medicine, Tel-Aviv University.
authors.forename: Sharon
authors.initials: S
authors.lastname: Stern
authors.affiliation: Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin, Israel, affiliated with the Sackler School of Medicine, Tel-Aviv University.
authors.forename: Zvi
authors.initials: Z
authors.lastname: Vaknin
authors.affiliation: Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin, Israel, affiliated with the Sackler School of Medicine, Tel-Aviv University.
authors.forename: Noam
authors.initials: N
authors.lastname: Smorgick
authors.affiliation: Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin, Israel, affiliated with the Sackler School of Medicine, Tel-Aviv University.
authors.forename: David
authors.initials: D
authors.lastname: Schneider
authors.affiliation: Department of Obstetrics and Gynecology, Assaf Harofe Medical Center, Zerifin, Israel, affiliated with the Sackler School of Medicine, Tel-Aviv University.
authors.forename: Reuvit
authors.initials: R
authors.lastname: Halperin
mesh_terms: D000028:Abortion, Induced / Q000379:methods*; D000030:Abortion, Missed / Q000601:surgery*; D000328:Adult; D016022:Case-Control Studies; D004106:Dilatation / Q000379:methods*; D005260:Female; D020073:Gravidity; D006801:Humans; D007795:Laminaria; D016015:Logistic Models; D008875:Middle Aged; D015999:Multivariate Analysis; D013513:Obstetric Surgical Procedures / Q000379:methods; D010298:Parity; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D017211:Treatment Failure
keywords: Abortion; Dilatation & evacuation; Inadequate cervical dilation; Laminaria; Risk factors