title: Impact of preoperative hormonal stimulation on postoperative complication rates after hypospadias repair: a meta-analysis.
abstract: BACKGROUND
  To improve the surgical outcome of hypospadias repair surgery, preoperative hormonal stimulation (PHS) has been proposed. We conducted a meta-analysis to evaluate the impact of preoperative hormonal stimulation (PHS) treatment on complication rates following hypospadias repair surgery.
  
  
  METHODS
  A comprehensive literature search up to June 1st, 2015 was carried out for relevant studies. After literature identification and data extraction, relative ratio (RR) was calculated to compare postoperative complication rates. Heterogeneity among individual studies was tested using the Cochran χ2 Q test and quantified by calculating the I2 index. Meta-regression was applied to find potential affective factors.
  
  
  RESULTS
  Overall, 428 patients from 6 studies had undergone primary hypospadias repair, of which 171 (39.95%) received some form of PHS with human chorionic gonadotropin (HCG), dihydrotestosterone (DHT) or testosterone (T). They underwent three different types of surgical techniques, including onlay island flap (N.=277), tubularized incised plate (N.=99) and Koyanagi urethroplasty (N.=52). These 6 studies classified the complication rates based on PHS. The relative ratio (RR) for a complication occurring following PHS use was 1.18 (95% CI: 0.70-2.00, Z=0.91, P=0.539). Significant heterogeneity (I2=47.1%, P=0.092) among various research literature was found and meta-regression was undertaken for the heterogeneity, but surgical technique, mean age of patients at time of surgery, types of PHS and the quality of studies were not the cause of heterogeneity.
  
  
  CONCLUSIONS
  Use of T, DHT and HCG prior to hypospadias repair does not appear to increase the incidence of postoperative complications, but further investigation is needed.
authors.affiliation: Department of Urology, Anhui Provincial Children's Hospital, Hefei, China.|Department of Urology, First Affiliated Hospital of Anhui Medical University, Hefei, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chao
authors.affiliation: Department of Urology, First Affiliated Hospital of Anhui Medical University, Hefei, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Urology, Anhui Provincial Children's Hospital, Hefei, China - liang_chaozhao@163.com.
authors.forename: Chaozhao
authors.initials: C
authors.lastname: Liang
mesh_terms: D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D013196:Dihydrotestosterone / Q000008:administration & dosage*; D006801:Humans; D007021:Hypospadias / Q000188:drug therapy* / Q000601:surgery*; D008297:Male; D011183:Postoperative Complications / Q000401:mortality / Q000517:prevention & control; D011300:Preoperative Care / Q000379:methods; D013739:Testosterone / Q000008:administration & dosage*
chemical_list: D006063:Chorionic Gonadotropin; D013196:Dihydrotestosterone; D013739:Testosterone