Embryo transfer (ET) is the technique of removing (flushing) an embryo from the uterus of one mare — the biological dam — and placing it in the uterus of a recipient mare.

The recipient carries the foetus, delivers the foal and nurses it until weaning. This allows high-class mares to continue their competitive careers while producing foals, or breed more than one foal from a mare each season.

ET first emerged in the 1970s and has become increasingly popular over the past 10 years.

The Gloucestershire-based Beaufort Embryo Transfer centre, one of the leaders in the field, handled 90 ET pregnancies in 2012.

Costs vary hugely, depending on whether you hire a recipient mare and how much veterinary influence or livery at the ET facility you require.

You can choose an all-in package, or separate “extras”, such as the insemination and scans. A minimum of two potential surrogate mares is required, as they have to synchronise oestrus cycles with the donor mare.

Currently, there is typically around a 45% chance of a successful pregnancy from a single oestrus cycle, meaning two or three attempts are often required.

Centres generally quote figures of around £1,900 (before VAT) for up to three cycles, if you supply the recipient mare and pay the cost of semen used. This includes veterinary examinations, drugs, insemination, flushing and transfer of embryos, but not livery for the donor and recipient mares.

Many centres hire out recipient mares for around £1,400 for the period from conception to weaning.

This article was first published in the current sport horse special (part two) of H&H (11 April 2013), where we look at why purchasers are still shopping abroad, changing trends in showing breeding and the success of the Algotsson family