Evaluation of the effect of metformin and aspirin on utero placental circulation of pregnant women with PCOS

Background: Women with polycystic ovary syndrome (PCOS) often are infertile and even if they become pregnant, there are complications with some adverse outcomes. It has been reported that aspirin and metformin improve uteroplacental circulation and reduce pregnancy complications.
Objective: To determine and compare uteroplacental circulation and obstetrics complications in pregnant women with PCOS treated with metformin, aspirin and control group.
Materials and Methods: 105 pregnant women with PCOS were enrolled in this study after assessing uterine artery pulsatility index (PI) with Doppler ultrasonography at 12 weeks of gestation. The patients were divided into three groups and received metformin 2000 mg or aspirin 80 mg daily, or no intervention until the end of pregnancy. PI was assessed for the patients at 20 week of gestation and groups were followed up till delivery. PI and obstetrics complications such as gestational diabetes, preterm labor, preeclampsia and IUGR were compared among groups.
Results: All groups had significant reduction in the mean uterine artery PI at 20 weeks measurement (p <0.05), but this reduction was more in metformin and aspirin groups than control group (p=0.002). There was a significant difference in mean uterine artery PI 20 week of gestation in three groups (p=0.005). Adverse outcomes have seen 4 out of 35 in metformin group, 7 out of 35 in aspirin group and 11 out of 35 in control group. There weren’t significant differences among groups (p=0.12).
Conclusion: Metformin and low dose aspirin reduced uterine artery impedance but there was not associated with reduced obstetrics complication in women with PCOS.