Prevalence of chromosomal abnormalities in Sri Lankan women with primary amenorrhea

Abstract

Chromosomal abnormalities are implicated in the etiology of primary amenorrhea. The underlying chromosomal aberrations are varied and regional differences have been reported. The objective of this study is to describe the prevalence of various types of chromosomal abnormalities in Sri Lankan women with primary amenorrhea. Medical records of all patients diagnosed with primary amenorrhea referred for cytogenetic analysis to two genetic centers in Sri Lanka from January 2005 to December 2011 were reviewed. Chromosome culture and karyotyping was performed on peripheral blood samples obtained from each patient. Data were analyzed using standard descriptive statistics. Altogether 338 patients with primary amenorrhea were karyotyped and mean age at testing was 20.5 years. Numerical and structural chromosomal abnormalities were noted in 115 (34.0%) patients which included 45,X Turner syndrome (10.7%), Turner syndrome variants (13.9%), XY females (6.5%), 45,X/46,XY (0.9%), 46,XX/46,XY (0.6%), 47,XXX (0.3%), 47,XX,+ mar (0.3%), 46,X,i(X)(p10) (0.3%), 46,XX with SRY gene translocation on X chromosome (0.3%) and 46,XX,inv(7)(p10;q11.2) (0.3%). Short stature, absent secondary sexual characteristics, neck webbing, cubitus valgus and broad chest with widely spaced nipples were commonly seen in patients with Turner syndrome and variant forms. Neck webbing and absent secondary sexual characteristics were significantly associated with classical Turner syndrome than variant forms. A considerable proportion of women with primary amenorrhea had chromosomal abnormalities. Mean age at testing was late suggesting delay in referral for karyotyping. Early referral for cytogenetic evaluation is recommended for the identification of underlying chromosomal aberrations in women with primary amenorrhea.