Abstract
Abstract
Study question
In this study, we evaluated the pregnancy, delivery and neonatal outcomes among women with an arcuate uterus.
Summary answer
The arcuate uterus is associated with multiple adverse pregnancy outcomes, particularly, increased risk for; cesarean delivery (CS), venous thromboembolism (VTE) and pulmonary embolism (PE).
What is known already
Congenital uterine anomalies (CUAs) have been associated with poor reproductive outcomes. The arcuate uterus is one of the most common CUAs, however, it is believed to be a variation of normal and should as such have minimal adverse effects on pregnancies. However, the published studies evaluating the effects of arcuate uteri on pregnancy outcomes, involved only small numbers of participants, and were not powered to detect differences, while reporting conflicting results.
Study design, size, duration
A retrospective population-based study was conducted using data from the Health Care Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS). Unique in-hospital births occurring between 2010 and 2014 were included. Cases of arcuate uterus were identified using the ICD code 752.36. A total of 3,840,147 control births and 754 in women with an arcuate uterus occurred during the study period. Pregnancies in women with an arcuate uterus were compared to those without CUAs.
Participants/materials, setting, methods
We assessed hypertensive disorders, gestational diabetes and placenta previa, preterm premature rupture of membranes (PPROM), preterm delivery, placental abruption, chorioamnionitis, delivery mode, bleeding, clotting and wound complications, maternal infections or death. Selected neonatal outcomes included small for gestational age(SGA), intrauterine fetal demise and congenital anomalies. A multivariate logistic regression was used to adjust for confounding effects. IRB approval was not required since the study included only publicly available anonymized data.
Main results and the role of chance
Women with an arcuate uteri were more likely to be older, Caucasian, with a higher income, and private insurance (P-value < 0.0001 all). They were also more likely to have had a Cesarean in the past, to have pre-gestational diabetes, thyroid disorders, an in-vitro pregnancy and multiple gestations (P-value <0.01 all). Pregnancies associated with the arcuate uterus had higher rates of pregnancy-induced hypertension (PIH) (aOR 1.32, 95% CI 1.03-1.70), preeclampsia (aOR 1.63, 95% CI 1.18-2.24), premature preterm rupture of membranes (PPROM) (aOR 2.86, 95% CI 1.86-4.40), preterm delivery (aOR 1.86, 95% CI 1.45-2.37) and placental abruption (aOR 3.08, 95% CI 1.99-4.77). They also had 10.88 times the odds of delivering via Cesarean (95% CI 8.90-13.30), 4.81 times the odds of suffering from a VTE (95% CI 1.20-19.30) and 15.14 times the odds of having a PE (95% CI 3.76-60.91). Small for gestational age (SGA) neonates were also more common (aOR 2.21, 95% CI 1.58-3.10).
Limitations, reasons for caution
The database may be affected by recall bias and coding issues. Information on the method of diagnosing arcuate uteri was lacking. However, to our knowledge, this is the largest study looking at the reproductive outcomes with the arcuate uterus. We were powered to adjust results to identified confounding factors.
Wider implications of the findings
Our study demonstrates that women with an arcuate uterus are at increased risk for certain undesirable pregnancy outcomes. Physicians following these women should be prepared to manage these complications. Since our results differ from those of some smaller cohorts, additional large studies should be undertaken to confirm the results.
Trial registration number
Not applicable