title: National birth rate, IVF utilisation and multiple gestation trends: findings from a 6-year analysis in the Republic of Ireland.
abstract: OBJECTIVE
  The impact of the advanced reproductive technologies on multiple gestation has been well documented in several large populations, but only infrequently in smaller countries, where its effects may be different. This study estimated domestic in vitro fertilisation (IVF) use and multiple gestation rate in Ireland based on two data-reporting platforms.
  
  
  METHODS
  The number of IVF cycles completed in Ireland was extrapolated from statistics reported to the central European fertility registry (ESHRE) between 1999 and 2004. Multiple gestation data during this period were obtained from the National Perinatal Reporting System (NPRS). These datasets were interlocked to offer a method to track the impact of IVF activity on background multiple gestation rate in Ireland.
  
  
  RESULTS
  Total Irish births registered increased from 54,307 in 1999 to 62,406 in 2004, and multiple gestation rate (per 1,000) fluctuated non-linearly from 27.2 to 31.4 during this time. Reported IVF activity increased from 972 in 1999 to 1,705 in 2004. Annual incidence of multiple gestation appeared strongly correlated with annual number of ETs although statistical significance was not reached (unadjusted Spearman correlation coefficient = 0.6; p = 0.21).
  
  
  CONCLUSIONS
  Although IVF providers must continue to reduce multiple births by limiting the number of embryos transferred, this study places national IVF activity in the context of multiple gestations recorded in the general Irish population. These datasets suggest the number of patients undergoing IVF increased steadily in Ireland from 1999 to 2004, but a similar increase in multiple gestation was not observed in the overall Irish population during our study interval. While it is reassuring that increased use of IVF in Ireland did not significantly influence the multiple gestation rate, the absence of a formal data collection method hampers direct and comprehensive monitoring of this phenomenon here.
authors.affiliation: The Sims Institute/Sims International Fertility Clinic, Rosemount Hall, Dundrum Road, Dundrum, Dublin 14, Ireland. drscottsills@sims.ie
authors.forename: Eric Scott
authors.initials: ES
authors.lastname: Sills
authors.forename: David J
authors.initials: DJ
authors.lastname: Walsh
authors.forename: Ahmed B
authors.initials: AB
authors.lastname: Omar
authors.forename: Umme
authors.initials: U
authors.lastname: Salma
authors.forename: Anthony P H
authors.initials: AP
authors.lastname: Walsh
mesh_terms: D000328:Adult; D001723:Birth Rate / Q000639:trends*; D005260:Female; D005307:Fertilization in Vitro / Q000706:statistics & numerical data* / Q000639:trends*; D006801:Humans; D007494:Ireland / Q000453:epidemiology; D008423:Maternal Age; D009099:Multiple Birth Offspring / Q000706:statistics & numerical data*; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data*; D012042:Registries / Q000706:statistics & numerical data