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Recently, assisted reproductive techniques have been used to prevent further miscarriages in women with recurrent miscarriage. One approach uses either screening or diagnosis of embryonic chromosomes prior to embryo replacement [preimplantation genetic screening (PGS)/preimplantation genetic diagnosis (PGD)]. The second approach involves surrogacy. However, PGS/PGD assumes that the embryo is chromosomally abnormal, and that the mother should receive a chromosomally normal embryo. Surrogacy assumes that the embryo is normal and that the maternal environment needs to be substituted. This article examines the place of both techniques in different types of recurrent miscarriage, and tries to give guidelines as to which technique is preferable depending on the likelihood of an embryonic chromosome aberration. In repeated fetal aneuploidy or in the older patient, PGS or PGD are preferable. However, with high numbers of miscarriages, or in autoimmune pregnancy loss, surrogacy is preferable. In the light of recent work, it is uncertain which treatment mode is indicated in balanced parental chromosome aberrations. In conclusion, both techniques have a place, but probably only in those patients with a poor prognosis in whom assisted reproductive techniques will be shown to improve the subsequent live birth rate above the spontaneous rate.