Kanda Takashi, Ogawa Masanobu, Sato Kazuo
Department of Pediatrics, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan.
AJP Rep. 2013 May;3(1):33-6. doi: 10.1055/s-0032-1331377. Epub 2013 Jan 2.
Traditionally, monochorionicity has been regarded as synonymous with monozygosity. However, several recent cases of monochorionic dizygotic twins have shown that monochorionic twins can be dizygous. We report a rare case of monochorionic diamnionic, gender-discordant twins who were conceived spontaneously. Initially, a monochorionic placenta was diagnosed by ultrasonography at 8 weeks of gestation and then confirmed by pathology after delivery. The twins had different genders. A comparison of cytogenetic analyses using peripheral blood lymphocytes and skin fibroblasts revealed that chimerism was confined to blood cells. We have experienced two cases of monochorionic dizygotic twins since 2003. These cases suggest that monochorionic dizygotic twins are not as rare as previously thought.
传统上，单绒毛膜性一直被视为与单合子性同义。然而，最近几例单绒毛膜双卵双胎的病例表明，单绒毛膜双胎也可能是双卵的。我们报告一例罕见的单绒毛膜双羊膜囊、性别不一致的自然受孕双胎。最初，在妊娠8周时通过超声诊断为单绒毛膜胎盘，分娩后经病理证实。这对双胎性别不同。使用外周血淋巴细胞和皮肤成纤维细胞进行的细胞遗传学分析比较显示，嵌合体仅限于血细胞。自2003年以来，我们已遇到两例单绒毛膜双卵双胎病例。这些病例表明，单绒毛膜双卵双胎并不像以前认为的那么罕见。
