Perinatal outcomes with a copper intrauterine device in situ after 28 gestational weeks: A retrospective study of sole center in southeast China.

The purpose of this study was to investigate the pregnancy outcomes with a copper intrauterine device (IUD) in situ after 28 gestational weeks and the association between pregnancy with copper IUDs and neonatal congenital malformations. This retrospective study had compared the singleton pregnancies with the copper IUDs in situ and without after 28 gestational weeks in 1 delivery center of southeast China. The main exposure was a copper IUD in uterine cavity with pregnancy. The pregnant outcomes as preterm birth, premature rupture of membranes, infections were observed and compared. We had also compared neonatal congenital malformations in 2 groups. The statistical analysis was carried out using R (version 4.0.4; R Development Core Team) statistical software. Association between IUD use or duration of IUD use and adverse pregnancy outcomes were estimated using logistic model. Two-tailed P value < .05 was deemed statistically significant. A total of 148 pregnant women were included in our study, 74 with copper IUDs in situ were categorized into case group and 74 without IUDs during pregnancy into control group. No significant difference of maternal age, BMI, birth weight and gender were observed between 2 groups. In case group, the rates of preterm premature rupture of membranes (37.8%) and spontaneous preterm birth (23.0%) were significantly high compared to control group. Odds ratios of premature rupture of membranes and spontaneous preterm birth were 2.86 and 5.22 respectively. Women of elder age (≥35 years) in case group were more likely to experience premature rupture of membranes. The rates of neonatal congenital malformation were 10.8% (8/74) in case group and 1.4% (1/74) in control group respectively. We had found that pregnancy with copper IUD in situ increased the risk of premature rupture of membranes and spontaneous preterm birth after 28 gestation weeks, the risk of spontaneous preterm birth increased 5.22 times. Pregnancy with IUD in situ may be at increased risk of infection and neonatal malformation.