Introduction

Turner's syndrome (TS) is the most common sex chromosome disorder among women, affecting 1 out of 2000 liveborn girls (Gravholt et al., 1996). The main characteristics of TS include short stature and failure to enter puberty; this resuts from an accelerated rate of atresia of ovarian follicles, causing gonadal insufficiency and infertility. There is also a wide range of additional morbidities associated with the syndrome, as many other organ systems and tissues may be affected to a lesser or greater extent. Therefore, the variability of amount and degree of medical and psychosocial problems between individuals is great and the effects on health and quality of life vary from slight to profound. The need for hormone replacement therapy (HRT) to promote growth and puberty gives the paediatric endocrinologist the most central role when caring for and treating girls with TS. Among women of adult age with TS, counselling on fertility problems puts the focus on the specialists in reproductive medicine and clinical genetics, who are important members of a multidisciplinary network of different specialists in the counselling team.

Genetics

TS is a combination of clinical features caused by complete or partial loss of the second sex chromosome, with or without cell line mosaicism. It is believed that over 50% of the women with TS have a complete loss of one X chromosome (i.e. monosomy 45,X), while 20% have one normal X chromosome together with a structurally altered X chromosome.