en Midwifery Orginal research <strong><em>Background:</em></strong> Hypothyroidism is common during pregnancy. This disorder is associated with adverse maternal and neonatal outcomes.<br> <strong><em>Objectives: </em></strong>The study of the prevalence and different consequences of hypothyroidism in pregnancy in each region is the special importance in determining prevention and management strategies. Therefore, the aim of this study was to determine the prevalence of hypothyroidism and pregnancy outcomes in women referred to Ayatollah Mousavi Hospital in Zanjan.<br> <strong><em>Methods:</em></strong> This cross-sectional-analytical study was performed on all pregnant women who gave birth in Ayatollah Mousavi Hospital in Zanjan in 2018-2019. Data were collected through census and using Chi-square, Fisher&#39;s exact and independent t-tests and with SPSS software version 22, pregnancy outcomes between the two groups were calculated.<br> <strong><em>Results</em></strong><strong>:</strong> The prevalence of hypothyroidism in pregnant women in the present study was estimated at 8.59%. Hypothyroidism was found to double the chance of gestational diabetes (p<0.02) (CI=1.1-3.8). The rate of cesarean delivery was significantly higher in patients (p<0.001). The rate of fetal heart rate drop, placental abruption, and placental adhesion was higher in the affected group, but this difference was not significant (p>0.05). There was no significant difference between the two groups in terms of preeclampsia, preterm delivery, first minute Apgar score, height, weight and head circumference of the newborn (p>0.05).<br> <strong><em>Conclusion:</em></strong> Considering the adverse maternal and neonatal outcomes of hypothyroidism, it seems that more clinical studies in this field are needed to manage and evaluate the outcomes in pregnant women with hypothyroidism prevalence, hypothyroidism, pregnancy outcomes, neonatal outcomes 48 54 http://nmcjournal.zums.ac.ir/browse.php?a_code=A-10-750-1&slc_lang=en&sid=1 Fatemeh Bayat f.bayat680@gmail.com 0000-0002-1811-3738 No Ph.D student, Instructor, Department of Midwifery, School of Nursing and Midwifery, Zanjan University of Medical Sciences, Zanjan, Iran Monireh Rezaee Moradali monir.rezaee@yahoo.co.uk 0000-0002-6450-7578 No Ph.D student of reproductive health, Student Research Committee, Midwifery and Reproductive Health Research Center, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran Sahar Roozbahani s.roozbahani1217@gmail.com 0000-0002-2426-2115 No Ph.D student of reproductive health, Student Research Committee, Midwifery and Reproductive Health Research Center, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran Shabnam Towfighi shabnam_towfighi61@yahoo.com 0000-0001-8117-5176 No Assistant Professor of Obstetrics and Gynecology, Department of Obstetrics and Gynecology, School of Medicine, Ayatollah Mousavi Hospital, Zanjan University of Medical Sciences Maryam Shami mshami@razi.tums.ac.ir 0000-0002-7824-457X Yes master student, Tehran university of medical sciences, school of nursing and midwifery, Tehran, Iran