title: Recurrent ectopic pregnancy as a unique clinical sub group: a case control study.
abstract: BACKGROUND
  Women with recurrent ectopic pregnancy (EP) represent a unique cohort of patients in whom diagnostic expertise is paramount. We determined whether recurrent EP is associated with significant differences in patient demographics, clinical presentation, risk factors and surgical findings when compared with primary EP.
  
  
  METHODS
  A retrospective case-control study of all EPs diagnosed from 2003 to 2014, at Whipps Cross University Hospital, London.
  
  
  RESULTS
  In the above period 849 EPs were surgically managed (758 primary EPs and 91 recurrent EPs). Recurrent EPs were significantly older than primary EPs (32.2 ± 5.08 vs. 30.5 ± 5.83 years, p < 0.05). They presented at a significantly earlier gestation (5.99 ± 1.08 vs. 6.52 ± 1.81 weeks, p < 0.05) and with a significantly lower primary βHCG (3176 ± 7350 vs. 6243 ± 12,282, p < 0.05). Recurrent EPs were significantly more likely to have a positive history of tubal or pelvic surgery (61.5 % vs. 3.5 %, p < 0.05 and 53.8 vs. 14 %, p < 0.05). At surgery, primary EPs had a significantly greater volume of hemoperitoneum (592 ± 850 vs. 249 ± 391 ml, p < 0.05), whereas recurrent EPs were significantly more likely to have contralateral pathology (31.1 vs. 9.8 %, p < 0.05). Regression analysis showed that the parameters of age, gestational age at presentation, first βHCG level, positive history of previous tubal surgery and previous ectopic pregnancy differ in women at risk of a recurrent EP when compared to women not at risk of a recurrent ectopic (AUC, 0.844).
  
  
  CONCLUSIONS
  We conclude that recurrent EPs may represent a unique sub-group of patients with EP.
authors.affiliation: Department of Gynaecology, Whipps Cross University Hospital, Barts Health Trust, Whipps Cross Road, Leytonstone, London, E11 1NR UK.
authors.forename: Alice
authors.initials: A
authors.lastname: Hurrell
authors.affiliation: Department of Gynaecology, Whipps Cross University Hospital, Barts Health Trust, Whipps Cross Road, Leytonstone, London, E11 1NR UK.
authors.forename: Oliver
authors.initials: O
authors.lastname: Reeba
authors.affiliation: Department of Gynaecology, Whipps Cross University Hospital, Barts Health Trust, Whipps Cross Road, Leytonstone, London, E11 1NR UK.
authors.forename: Odejinmi
authors.initials: O
authors.lastname: Funlayo
keywords: Diagnosis; Ectopic pregnancy; Laparoscopy; Recurrent ectopic pregnancy