Assistant Professor of Radiology, Department of Radiology, Poursina Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
Resident of Radiology, Reproductive Health Research Center, Student Research Committee, Guilan University of Medical Sciences, Rasht, Iran
Assistant Professor of Obstetrics and Gynecology, Reproductive Health Research Center, Department of Obstetrics &amp; Gynecology, Al-Zahra Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
Associate Professor, Department of Biostatistics, Social Determinants of Health Research Center, Guilan University of Medical Sciences, Rasht, Iran.
Background: The low level of pregnancy-associated plasma protein A (PAPP-A) has a close relationship with unfavorable outcomes in neonates. We conducted this study to evaluate the association between thickness and size of placenta in 18-23 weeks and PAPP-A level at gestational age in 11 to 14 weeks in singleton pregnant women referred to Al-Zahra Hospital, Guilan.
Materials and Methods: In this prospective cohort study, we investigated 102 women with singleton pregnancy between August 2017 to June 2018. Serum PAPP-A of pregnant women was measured in the first trimester of pregnancy. Patients who had PAPP-A ≤0.5 Multiple of the Median (MOM (were dedicated to exposed group and others to non-exposed group. Placental thickness and size were assessed during second trimester by ultrasound examination and described as abnormal high thickness if the thickness was > 4 cm or more than 50% of placental length and abnormally small size when the maximum length was < 10 cm. Placental thickness and size of the two groups were compared using the Mann-Whitney u test.
Results:The mean age of the patients was 28.2 (SD: 5.2) years and the means of gestational age in exposed and non-exposed groups was 20.38 and 20.84 weeks, respectively (P=0.203). Sixty-eight patients had PAPP-A >0.5 and 34 patients had PAPP-A ≤0.5. Women with low levels of PAPP-A in the first trimester had an increased incidence of abnormal placental thickness in 13 cases, and small placental size in 7 cases, whereas this number in another group was 12 and 7 cases, respectively (P=0.023). We found the sensitivity and specificity of PAPP-A<0.55 were 72.3% and 56% for abnormal placental thickness, respectively. Moreover, the sensitivity and specificity of PAPP-A< 0.55 were 69.3% and 57.1% in the assessment of abnormal placenta size, respectively.