Evaluation of prevalence of Thyroid Peroxidase Antibody and therapeutic effect of levothyroxine on pregnancy outcome in positive antibody pregnant women

Document Type : Original Article


1 Associate professor, Department of Obstetrics and Gynecology, School of Medicine, Kurdistan University of Medical Sciences, Kurdistan, Iran.

2 Resident of Obstetrics and Gynecology, School of Medicine, Kurdistan University of Medical Sciences, Kurdistan, Iran.

3 Assistant professor, Department of Obstetrics and Gynecology, School of Medicine, Kurdistan University of Medical Sciences, Kurdistan, Iran.


Introduction: Thyroid peroxides antibodies are associated with recognized complications during and after pregnancy like Abortion and postpartum depression, but other complications such as preterm labor, preterm rupture of membrane(PROM) and effect of antibodies on newborns weight and newborns Apgar score not be evaluated. Studies were demonstrated, treatment with levothyroxine in pregnant women with thyroid peroxides antibodies may prevent maternal and fetal complications. This study illustrated the prevalence of thyroid peroxides antibodies and induced pregnancy complications and then evaluates the effects of levothyroxine in reducing pregnancy complications among pregnant women having such antibodies.
Methods and materials: we designed single blind RCT study in 300 first trimester pregnant women attending Prenatal Clinic in Sanandaj from September 2009 to January 2011. of 266 pregnant women without clinical hypothyroidism, 32 women were thyroid peroxides antibody positive. This 32 thyroid peroxides antibody positive women were divided in two groups via simple randomized allocation. Intervention group received a daily dose of 50 microgram levothyroxine in the pregnancy period. Control group did not receive any treatment. Participants were observed until the end of pregnancy period and outcome was assessed. Then data was analyzed by SPSS 11.5 software and Chi square, Fisher and Kruskal-Wallis test. P-values less than 0.05 were considered statistically significant.
Results: of 266 pregnant women, 32 women (12%) were thyroid peroxides antibody positive. There were no significant statistical differences between delivery type and delivery time. (p=0.37) Though premature delivery and premature rupture of membrane in treated group was lower than non-treated group and the average of newborns weight and newborns Apgar score was higher than non-treated group, this difference was not statistically significant. (p=0.22, p=0.34 and p=0.16)
Conclusion: Add tests for thyroid peroxidase antibodies to pregnancy care and treatment with levothyroxine in pregnant women with thyroid peroxides antibodies can reduce premature delivery and premature rupture of membrane and increase the average of newborns weight and newborns Apgar score.


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