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Updated: Aug 23, 2026

Multiplexed Fluorescent Immunohistochemical Staining of Four Endometrial Immune Cell Types in Recurrent Miscarriage
Published on: August 4, 2021
Embryo loss pattern is predominant in miscarriages with normal chromosome karyotype among women with repeated
Mamoru Morikawa1, Hideto Yamada, Emi H Kato
1Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Kita-ku N15 W7, Sapporo 060-8638, Japan.
Objective:
The aim of this study was to assess pregnancy loss patterns in women with repeated miscarriage (RM), according to fetal chromosome karyotypes and aetiologies of RM.
Methods:
In this cohort study, 168 fetal chromosome karyotypes of miscarriages were investigated. The pregnancy loss patterns were compared between 75 miscarriages from RM women who had a history of two or more consecutive miscarriages and 93 miscarriages from control women whose previous pregnancies ended in live births without a history of RM. By serial ultrasonography, embryo loss (EL) was defined as miscarriage before fetal heat movement was identified and fetal loss (FL) as miscarriage after fetal heat movement was identified. The EL rate was calculated as EL/(EL+FL).
Results:
The EL rate (66.7%) in miscarriages with normal karyotypes among RM women (n=42) was higher (P<0.05) than that (45.7%) in controls (n=46), while the EL rate (30.3%) in miscarriages with abnormal karyotypes among RM women (n=33) did not differ from that (25.5%) in the controls (n=47). The EL rate (71.4%) in miscarriages with normal karyotypes among unexplained RM women (n=21) was much higher (P<0.05) than that in the controls.
Conclusions:
By evaluating fetal karyotypes, we demonstrated for the first time that EL was predominant in miscarriages with normal karyotype among RM women.
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