Foreword

In 1980 in the United States, that is before in vitro fertilization (IVF) or the widespread use of ovulatory drugs, some 1.8% of all births were multiple – mostly twins. By the mid first decade of the twenty-first century, this figure has doubled and many of the births have been of triplets or more. Other nations have had a similar experience. This is no trivial matter. Fortunately, most neonate twins and triplets are normal, but multiples have problems – even twins – and these problems can be serious, such as mental retardation. Many reproductive endocrinologists and other users of ovulatory drugs are really not focused on the plight of multiples for the simple reason that in this age of specialization they do not participate in the obstetrical or pediatric care of their successful patients. In this twenty-first century, it is truly time that those called upon to overcome infertility strive to produce not a baby, but a normal healthy baby. If these observations have merit, every reproductive endocrinologist or other user of ovulatory drugs would benefit his or her patients by reading the first chapter of Single Embryo Transfer. This chapter by Wennerholm titled, “The risks associated with multiple pregnancies” spells out the reasons to do everything possible to avoid multiples. For those who use ovulatory drugs, one of the things possible is elective single embryo transfer (eSET) by those who use IVF and have a patient to which it can be applied.