We appreciate the interest and comments by Yeh CC et al1 on our study.2They proposed some questions in different sections to improve the quality of the study.
In the “Results” section, we must mention that the mean of abortion was 2.75 in the recurrent miscarriage group and the mean of deliveries (parous) was 1.45 in the control group. Of course, we have excluded women with stillbirth and death child in the control group.
In the “Methods” section, it should be expressed that immune processes have a main effect in recurrent miscarriage.3 Recurrent pregnancy loss (RPL) is the most common form of fertility failure that is defined as loss of two or more pregnancy before the 20th week of pregnancy.4 Therefore, the implantation is done at this time. On the contrary, a study has shown that natural killer (NK) cells can also play a role in the continuation of pregnancy by binding to HLA-G and secretion of growth factors for the fetus.5 Therefore, the role of NK cells is essential in the continuation and maintenance of the pregnancy to the term. In this study, we have noticed this aspect of the role of NK cells. Also, our sampling was 8 weeks after the abortion and that there was no implantation at this time.
Finally, NK cells with up-regulated cytotoxic phenotypic are important in RPL. Also, the regulatory role of NK cells is important in maintaining and continuation of the pregnancy.6 In our study, the phenotypes mentioned may be important in this role (regulatory).
This study was supported by a research grant (9434919) from Babol University of Medical Sciences.
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