Absent and Infrequent Periods: Karyotyping -checksum="50019" ends

There are normally 23 pairs of chromosomes (Q 2.5). It occurs in one in 2000 girls in the UK. Girls have two X chromosomes and there is one X and one Y chromosome in boys. Women with Turner's syndrome have only one sex chromosome X0 rather than XX. Intellectual capacity is normal. They are born without functional ovaries and they tend to be of short stature and have web-shaped necks. The endocrine picture is usually typical of the menopause so hormone replacement therapy is indicated probably from the mid-teens. This is likely to improve bone density in the long-term and improve femininity. Pregnancy can only occur using donated eggs and in vitro fertilisation (IVF27).

Sometimes, notably when only some cells have one chromosome only and others are normal, there may be periods although premature ovarian failure is likely. Spontaneous pregnancy is rare.