Study protocol: E-freeze - freezing of embryos in assisted conception: a randomised controlled trial evaluating the clinical and cost effectiveness of a policy of freezing embryos followed by thawed frozen embryo transfer compared with a policy of fresh embryo transfer, in women undergoing in vitro fertilisation.

Background: Infertility affects one in seven couples; many of these need in vitro fertilisation (IVF). IVF involves external hormones to stimulate a woman's ovaries to produce eggs which are harvested surgically. Embryos, created in the laboratory by mixing eggs with sperm, are grown in culture for a few days before being replaced within the uterus (fresh embryo transfer).

Adjuncts in the IVF laboratory: where is the evidence for 'add-on' interventions?

Globally, IVF patients are routinely offered and charged for a selection of adjunct treatments and tests or 'add-ons' that they are told may improve their chance of a live birth, despite there being no clinical evidence supporting the efficacy of the add-on. Any new IVF technology claiming to improve live birth rates (LBR) should, in most cases, first be tested in an appropriate animal model, then in clinical trials, to ensure safety, and finally in a randomized controlled trial (RCT) to provide high-quality evidence that the procedure is safe and effective. Only then should the technique be considered as 'routine' and only when applied to the similar patient population as those studied in the RCT.

Elective Single Embryo Transfer: an update to UK Best Practice Guidelines.

A significant number of multiple pregnancies and births worldwide continue to occur following treatment with Assisted Reproductive Technologies (ARTs). Whilst efforts have been made to increase the proportion of elective single embryo transfer (eSET) cycles, the multiple pregnancy rate or MPR remains at a level that most consider unacceptable given the associated clinical risks to mothers and babies, and the additional costs associated with neonatal care of premature and low birth weight babies. Northern Europe, Australia and Japan have continued to lead the way in the adoption of eSET.

How should we choose the 'best' embryo? A commentary on behalf of the British Fertility Society and the Association of Clinical Embryologists.

Embryo selection to improve pregnancy rates remains a significant challenge in IVF. Non-invasive and invasive methods of embryo selection include morphological assessment, metabolomics, time-lapse imaging and preimplantation genetic screening. To date, none has been shown conclusively to yield improved implantation and live birth rates.