title: A logistic model to predict early pregnancy loss following in vitro fertilization based on 2601 infertility patients.
abstract: BACKGROUND
  According to previous studies, even after embryonic cardiac activity is detected, the pregnancy loss rate remains 3-4 %. The objectives of this study were to investigate the differences in ultrasound parameters between a miscarriage group and an ongoing pregnancy group during the 1(st) trimester and to build a logistic model to predict early pregnancy loss (EPL) after the appearance of embryonic cardiac activity in patients who have undergone in vitro fertilization embryo transfer (IVF-ET) treatment.
  
  
  METHODS
  A total of 2601 patients with early singleton pregnancies with embryonic cardiac activity were retrospectively analyzed after IVF from January 2010 to June 2011. Transvaginal sonography (TVS) was performed at 6 to 10 weeks of gestational age (GA). The mean gestational sac diameter (MSD), crown-rump length (CRL), fetal heart rate (FHR), and yolk sac diameter (YSD) were measured by TVS.
  
  
  RESULTS
  A total of 2400 patients had an ongoing pregnancy and an additional 201 (7.7 %) patients miscarried during the first trimester after fetal cardiac activity had been established. The maternal age (MA) and infertility duration were much greater, and the MSD, CRL, and FHR were much lower in the miscarriage group than in the ongoing pregnancy group after IVF (P < 0.05). The prediction model utilized the following equation: the possibility of EPL = exp(z)/(1 + exp(z)), where z = -21.456 + (0.114 × MA) + (4.305 × × GA) - (0.043 × MSD) - (0.359 × CRL) - (0.091 × FHR) + 2.243 (fluid collection present around the gestational sac (GS)) + 2.519 (when YSD < 3) or - 0.347 (when YSD > 5.5).
  
  
  CONCLUSIONS
  The MA, MSD, CRL, YSD, FHR, infertility duration, and fluid collection around the GS were each correlated with EPL after IVF in infertile patients. A logistic model is a useful tool for predicting EPL after the appearance of embryonic cardiac activity (area under the curve [AUC] = 0.909).
authors.affiliation: Institute of Reproductive and Stem Cell Engineering, Central South University, Xiangya Road, Changsha, 410078, Hunan, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yi
authors.affiliation: Institute of Reproductive and Stem Cell Engineering, Central South University, Xiangya Road, Changsha, 410078, Hunan, P. R. China.|Reproductive and Genetic Hospital of CITIC-Xiangya, Xiangya Road, Changsha, 410078, Hunan, P. R. China.
authors.forename: Guangxiu
authors.initials: G
authors.lastname: Lu
authors.affiliation: Institute of Reproductive and Stem Cell Engineering, Central South University, Xiangya Road, Changsha, 410078, Hunan, P. R. China.|Reproductive and Genetic Hospital of CITIC-Xiangya, Xiangya Road, Changsha, 410078, Hunan, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ouyang
authors.affiliation: Institute of Reproductive and Stem Cell Engineering, Central South University, Xiangya Road, Changsha, 410078, Hunan, P. R. China.|Reproductive and Genetic Hospital of CITIC-Xiangya, Xiangya Road, Changsha, 410078, Hunan, P. R. China.
authors.forename: Ge
authors.initials: G
authors.lastname: lin
authors.affiliation: Institute of Reproductive and Stem Cell Engineering, Central South University, Xiangya Road, Changsha, 410078, Hunan, P. R. China.|Reproductive and Genetic Hospital of CITIC-Xiangya, Xiangya Road, Changsha, 410078, Hunan, P. R. China.
authors.forename: Fei
authors.initials: F
authors.lastname: Gong
authors.affiliation: Reproductive and Genetic Hospital of CITIC-Xiangya, Xiangya Road, Changsha, 410078, Hunan, P. R. China. xihongliyxk@163.com.
authors.forename: Xihong
authors.initials: X
authors.lastname: Li
mesh_terms: D000022:Abortion, Spontaneous / Q000000981:diagnostic imaging*; D018568:Crown-Rump Length; D004624:Embryo Transfer; D005260:Female; D006340:Heart Rate, Fetal; D006801:Humans; D016015:Logistic Models; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal; D015017:Yolk Sac / Q000000981:diagnostic imaging
keywords: Crown-rump length; Early pregnancy loss; Fetal heart rate; In vitro fertilization embryo transfer; Logistic model; Mean gestational sac diameter