Effects of iron metabolism on pregnancy outcomes in patients with polycystic ovary syndrome

Abstract

Objective To evaluate the effect of iron metabolism on pregnancy outcomes in patients with polycystic ovary syndrome (PCOS). Methods From March 2013 to January 2015, a total of 50 cases of PCOS pregnant women with less than 8 gestational weeks′ gestation in Yan′an University Affiliated Hospital were admitted into PCOS group (n=50). Besides, 50 cases of healthy pregnant women with less than 8 gestational weeks′ gestation without any evidence of high level of androgen or ovulatory dysfunction in the same hospital during the same period were enrolled as control group (n=50). When pregnant women in two groups were at 8 gestational weeks′ gestation, the levels of serum androstenedione, total testosterone, glucose, insulin and homeostasis model assessment for insulin resistance (HOMA-IR) in two groups were detected. Levels of seum hemoglobin (Hb), hematocrit (HCT), iron, and total iron-binding capacity (TIBC) as well as level of serum ferritin were also serially detected at 8, 12, 20, and 32 gestational weeks′ gestation. Pregnancy outcomes of pregnant women and the outcomes of their neonates were observed in both groups. The study protocol was approved by the Ethical Review Board of Yan′an University Affiliated Hospital. Informed consent was obtained from every patient. Results ①There were no significant differences between two groups in the age, gestational age, body weight, body mass index, systolic blood pressure and diastolic blood pressure (P>0.05). ②Compared with control group, levels of serum androstenedione, total testosterone, insulin and HOMA-IR at 8 gestational weeks′ gestation were significantly higher in PCOS group (t=5.10, 7.04, 4.58, 4.56; P 0.05). ③There were no significant differences between two groups in the levels of serum Hb and HCT at 8 and 12 gestational weeks′ gestation (P>0.05). While at 20 and 32 gestational weeks′ gestation, the levels of serum Hb and HCT in PCOS group were significantly lower than those in control group, and all the differences were statistically significant (level of serum Hb: t=2.32, 2.31; P=0.023, 0.023; HCT: t=2.05, 2.20; P=0.043, 0.030). There were no significant differences between groups in levels of serum iron and TIBC at 8, 12, 20 and 32 gestational weeks′ gestation (P>0.05), whereas levels of serum ferritin in PCOS group were significantly higher than those in control group (t=6.00, 6.56, 11.60, 9.82; P 0.05). The rate of spontaneous abortion in PCOS group was significantly higher than that in control group, and the difference was statistically significant (χ2=5.01, P=0.025). The proportion of normal gestational age infants in PCOS group was lower than that in control group, while the proportions of small for gestational age and large for gestational age infants in PCOS groups were higher than those in control group (χ2=7.67, 5.22, 4.05; P=0.006, 0.022, 0.044). There was no significant difference in the rate of fetal malformations between two groups (P>0.05). ⑤In PCOS group, the serum ferritin level at 32 gestational weeks′ gestation of PCOS pregnant women with spontaneous abortion was significantly higher than that of PCOS without spontaneous abortion (t=2.36, P=0.022). Conclusions Compared with health pregnant women, pregnant women with PCOS have higher serum ferritin levels and iron metabolism disorders, and more adverse events occurred in neonates. Key words: Polycystic ovary syndrome; Iron metabolism; Serum ferritin; Pregnancy outcome; Pregnant women