Fetal trisomy 16 is considered uniformly lethal early in gestation. It has been reported to be associated with the variability of clinical features and outcomes. Mosaic trisomy 16 leads to a high risk of abnormality in prenatal cases. Intrauterine growth retardation (IUGR) is a common outcome of mosaic trisomy 16. Herein, we report on the case of Thai male IUGR fetus with trisomy 16 mosaicism. The fetal body was too small. Postmortem investigation of placenta revealed the abnormality including small placenta with furcated cord insertion and single umbilical cord artery. Cytogenetic study demonstrated trisomy 16 that was found 100% in placenta and only 16% in the fetal heart while other organs had normal karyotype. In addition, cardiac and other internal organs examination revealed normal morphology.

Reported cases of female hemophilia are rare. The possible causes include homozygous female (1-2) resulting from a hemophiliac father and a carrier mother, heterozygous female with extreme lyonization (3) or abnormal chromosome such as Turner's or functional Turner's Syndrome possessing a defective factor VIII gene (4). The molecular basis of severe hemophilia A in a girl resulting from two de novo factor VIII mutations of maternal X chromosome deletion and paternal factor VIII mutation of inversion of intron 22 was reported by Windsor in 1995 (5). The complete genetic evaluation of a female patient who manifests X linked disease is essential. We report here a one-year and 7-month-old girl with severe hemophilia A. She had two elder brothers who succumbed to excessive bleeding in early childhood. No other relatives with bleeding disorder or consanguineous marriage were know. The patient started to have excessive bruising since one year of age. She also experienced excessive gum bleeding and hemarthrosis at the knee after minor trauma. The physical examination revealed the body weight of 8.5 kg, height 75 cm, multiple bruises at the extremities, webbing of the neck, low hairline, cubitus valgus and broad-spaced nipples. The laboratory findings included APTT 120 sec (N 30-38sec), factor VIII clotting activity, < 1%, von Willebrand factor antigen, 98% and ristocetin cofactor, 105% while both parents had normal hematological studies. The chromosome study by the short term lymphocyte culture showed 45, XO. The linkage analysis of restriction fragment length polymorphisms of Bcl I at the intron 18 and variable dinucleotide tandem repeats at the intron 22 of the factor VIII gene was performed by polymerase chain reaction. The results showed that the patient inherited only the maternal X chromosome without the paternal X chromosome. Additionally, Southern blot analysis for the inversion of intron 22 on factor VIII gene, which is commonly found in severe hemophilia A patients (6), was performed in the patient and her parents. The results demonstrated that the patient had an inversion of intron 22 and her mother was a carrier. Therefore, the reported female hemophiliac patient had Turner's Syndrome and inherited the hemophiliac gene of inversion of intron 22 from her carrier mother (Fig. 1).

Abortion is a common pregnancy complication. Fetuses with several types of chromosomal abnormalities are aborted during the first trimester, while others have a better chance of surviving. This research aims to study and compare the incidence and types of fetal chromosomal abnormalities during the first trimester of Thai pregnant women between miscarriages and intrauterine survivals. Cytogenetic and BACs-on-Beads™ assays were assessed from 2010 to 2020 in Ramathibodi Hospital using first trimester samples of 265 chorionic villi as a retrospective study. Chromosomal abnormalities were observed in 135 cases (50.94%) including 38.11% miscarriages and 12.83% intrauterine survivals. In total, 75.56% single autosomal trisomies, 18.52% sex chromosome aneuploidies, 5.19% double aneuploidies, and 0.74% structural abnormalities were detected. In miscarriages, all chromosomes were involved in abnormalities except chromosomes 1, 5, 8, 9, 11, and 17, while survivals had only trisomy 13, 18, 21, and sex chromosome aneuploidy. Trisomy 16 and 18 were the most common abnormalities in miscarriages and intrauterine survivals, respectively. The highest rate of chromosomal aberrations was demonstrated in 8–9⁺⁶ and 12–13⁺⁶ weeks of gestation in miscarriages and intrauterine survivals, respectively. Correlation between chromosomal abnormalities and maternal age &#x3c;35 years and ≥35 years was significant (<i>p</i> &#x3c; 0.05) in intrauterine survival and first trimester groups.