Counseling parents before prenatal diagnosis: Do we need to say more about the sex chromosome aneuploidies?

Abstract

Sex chromosome trisomies (SCT), an extra X chromosome in females (triple X, XXX), males with an extra X chromosome (Klinefelter syndrome, XXY) or an extra Y chromosome (XYY) occur because of errors during meiosis and are relatively frequent in humans. Their identification has never been the goal of prenatal diagnosis (PD) but they almost never escape detection by any of the methods commonly in use. Despite recommendations and guide‐lines which emphasize the importance of structured counseling before and after PD, most women remain unaware that testing for serious genetic abnormalities is more likely to uncover these trisomies. With the increasing use of PD more and more prospective parents receive a diagnosis of sex chromosome trisomies and are faced with the dilemma of whether to terminate the pregnancy or to carry it to term. Despite the dramatic and emotionally devastating consequences of having to make such a decision, they have little opportunity to consider in advance the possible outcomes of such a pregnancy and, rather than relying on their own feelings and judgements, are forced to depend on the advice of counseling professionals who may or may not themselves be fully aware of what having an extra sex chromosome can mean to the development of a child. We address here the principles of reproductive autonomy together with an analysis of the major issues that ought to be discussed with the parents before a PD is carried out in order to minimize detrimental effects caused by this unexpected finding. © 2013 Wiley Periodicals, Inc.

The Impact of Living with Klinefelter Syndrome: A Qualitative Exploration of Adolescents and Adults

“…In many instances, families are unaware of the possibility of a sex chromosome aneuploidy diagnosis until they are faced with a decision about a pregnancy that is no longer “normal,” but often associated with a mild phenotype (Lalatta and Tint 2013; Petrucelli et al 1998). A postnatal diagnosis of XXY is often delayed, if made at all, leaving families searching for answers to their son’s physical and neurodevelopmental concerns for years (Visootsak et al 2013).…”

“…A prenatal diagnosis of XXY is often considered incidental and some providers even dread it, as XXY is generally viewed as having mild clinical consequences, especially relative to the other trisomies routinely tested in the prenatal period. In many instances, families are unaware of the possibility of a sex chromosome aneuploidy diagnosis until they are faced with a decision about a pregnancy that is no longer Bnormal,^but often associated with a mild phenotype (Lalatta and Tint 2013;Petrucelli et al 1998). A postnatal diagnosis of XXY is often delayed, if made at all, leaving families searching for answers to their son's physical and neurodevelopmental concerns for years (Visootsak et al 2013).…”

Prenatal and Preimplantation Diagnosis

“…With contemporary and longitudinal data on outcomes of children born with SCA, more accurate phenotype information is available for parents now (Lalatta and Tint 2013 ). Only 45,X (Turner syndrome) is consistently associated with structural abnormalities, and is associated with a relatively consistent phenotype.…”

“…The reader is referred to review articles that describe these generally mild phenotypes (Lalatta and Tint 2013 ). Counseling based on this updated information has generally led to a diminished rate of TOP for these SCAs.…”

Pregnancy outcomes in prenatally diagnosed 47, XXX and 47, XYY syndromes: a 30‐year French, retrospective, multicentre study

“…Sex chromosome aneuploidies (SCAs) are the most frequent chromosomal abnormalities encountered in prenatal diagnosis. Although the large part of 45, X karyotype (associated with Turner syndrome) is diagnosed after abnormal ultrasound features are observed, other SCAs (such as 47, XXY, defined as Klinefelter syndromes (KS), 47, XXX and 47, XYY) are diagnosed fortuitously, and the finding is considered as uneventful . Indeed, most karyotyping is performed to exclude trisomy 21, the indications of which are typically advanced maternal age (AMA), abnormal serum markers, previous fetal chromosome abnormalities or a family history of genetic disease requiring prenatal diagnosis.…”