Home-based monitoring prior to frozen embryo transfer: the new gold standard?

In medically assisted reproduction, the proportion of frozen embryo transfer (FET) cycles is steadily increasing and has amounted to 35·5% of all treatment cycles in 2018. 1 Wyns C De Geyter C Calhaz-Jorge C et al. ART in Europe, 2018: results generated from European registries by ESHRE. Hum Reprod Open. 2022; 2022hoac022 PubMed Google Scholar Although no single specific preparation protocol results in better pregnancy rates, 2 Glujovsky D Pesce R Sueldo C Quinteiro Retamar AM Hart RJ Ciapponi A Endometrial preparation for women undergoing embryo transfer with frozen embryos or embryos derived from donor oocytes. Cochrane Database Syst Rev. 2020; 10CD006359 PubMed Google Scholar recent insights promote the natural cycle over the artificial cycle, because of the lower risk of obstetrical complications. 3 Zaat TR Kostova EB Korsen P Showell MG Mol F van Wely M Obstetric and neonatal outcomes after natural versus artificial cycle frozen embryo transfer and the role of luteal phase support: a systematic review and meta-analysis. Hum Reprod Update. 2023; dmad011 Crossref Google Scholar In The Lancet, Tjitske Zaat and colleagues reported results of Antarctica-2, their multicentre, randomised controlled trial conducted in the Netherlands, investigating whether home-based monitoring of ovulation to time natural cycle FET (NC-FET) was non-inferior to hospital-controlled monitoring. 4 Zaat T de Bruin JP Goddijn M et al. Home-based monitoring of ovulation to time frozen embryo transfers (Antarctica-2): an open-label, nationwide, randomised, non-inferiority trial. Lancet. 2023; (published online Sept 1.)https://doi.org/10.1016/S0140-6736(23)01312-0 Summary Full Text Full Text PDF Google Scholar The authors deserve recognition for this ambitious trial, including 1464 women over a 4-year period to explore a practical, patient-friendly, environmentally sustainable, and less costly approach to assisted reproduction. Women aged 18–44 years who had an ovulatory cycle were randomly allocated in a 1:1 ratio to perform one NC-FET cycle following either home-based monitoring or hospital-controlled monitoring, with ongoing pregnancy rate as the primary outcome. According to the results, home-based ovulation monitoring can be a valid instrument in a reproductive clinic's toolbox: non-inferiority was confirmed with an ongoing pregnancy rate of 152 (20·8%) of 732 in the home-based monitoring group and 153 (20·9%) of 732 in the hospital-based monitoring group (risk ratio 0·99 [90% CI 0·81 to 1·22] and risk difference –0·14 [90% CI –3·63 to 3·36]). The authors are planning to perform a cost-effectiveness analysis in the future. Although this important study could imply a change in clinical practice, the following considerations call for reflection before cancelling all hospital visits to monitor NC-FET. Home-based monitoring of ovulation to time frozen embryo transfers in the Netherlands (Antarctica-2): an open-label, nationwide, randomised, non-inferiority trialHome-based monitoring of ovulation is non-inferior to hospital-controlled monitoring of ovulation to time FET. Full-Text PDF