Anti-thyroid peroxidase antibody positivity and other obstetric complications in women with recurrent miscarriage

Abstract

INTRODUCTIONMiscarriage is defined as any pregnancy ending spontaneously prior the fetus can survive. Recurrent miscarriage, defined as loss of 3 or more consecutive pregnancies affects 1% of couples trying to conceive. The etiology of recurrent spontaneous miscarriage includes epidemiological factors such as maternal age and number of previous miscarriages, anti-phospholipids syndrome, genetic factors, anatomical factors, endocrine factors, immune factors; inherited thrombophillic defects. 1 Women with RPL can be classified into three separate groups, as primary, secondary and tertiary aborters. Primary aborters are women with no previous live birth, secondary aborters if there was a live birth followed by pregnancy losses, and tertiary aborters are women who had pregnancy losses followed by a live birth. ABSTRACTBackground: Thyroid dysfunction and autoimmunity are relatively common in women of reproductive age group and has been associated with various adverse pregnancy outcomes such as recurrent miscarriage, preeclampsia and preterm labour. The aim of this study was to find out association between anti-tpo antibody and recurrent miscarriage and to evaluate obstetric complications such as preeclampsia and preterm labour in them. Methods: This case control observational study was carried out from July 2014 to June2015 on 110 pregnant mothers out which 55 with history of recurrent miscarriage were cases and 55 without such history were controls. Results: The mean age of the cases were 24.18 yrs. Majority of pregnancy losses occurred between 9-14wks.The prevalence of anti-tpo antibody positivity in the study population was 15.45%.out of 55 cases 12 were positive for anti-tpo antibody(21.8%).Positive anti-tpo antibody was associated with high TSH level than the negative anti tpo antibody(p<.000).The prevalence of preeclampsia and preterm labour in recurrent miscarriage patients were 9.09% and 5.45% respectively which was not significantly higher than background risk.1 out of 5 patients with preeclampsia had anti-tpo positive and none with preterm labour had anti-tpo antibody positivity. Conclusions: The prevalence of thyroid autoimmunity was higher in patients with history recurrent miscarriage history than the control population. Even in women with biochemically normal thyroid function there was relationship between recurrent miscarriage and thyroid autoimmunity. Thus anti-tpo antibody could be risk marker for RSM. Screening for subclinical hypothyroidism (TSH >2.5 but<10) and anti-tpo antibody can be suggested as these identify women with increased risk of miscarriage.