Pregnancy outcomes of women with a congenital unicornuate uterus after IVF-embryo transfer.

Unicornuate uteri are caused by non-development of one Müllerian duct. The objective of this study was to investigate pregnancy outcomes of singleton and/or twin pregnancies in women with unicornuate uterus after IVF-embryo transfer (IVF-ET). The study group comprised 238 patients with a unicornuate uterus and the control group 818 patients with normal uterus. Compared with pregnancies with normal uterine morphology, a unicornuate uterus was associated with an increased risk of early pregnancy loss [adjusted odds ratio (aOR) 1.88, 95% confidence interval (CI) 1.25-2.83; P = 0.002], premature delivery (aOR 2.11, 95% CI 1.45-3.07; P < 0.001), perinatal mortality (aOR 3.35, 95% CI 1.89-5.94; P < 0.001), low birthweight (LBW, aOR 1.43, 95% CI 1.04-1.79; P = 0.005) and very low birthweight (VLBW, aOR 2.58, 95% CI 1.53-4.34; P < 0.001). Additionally, significantly lower rates of term delivery (aOR 0.43, 95% CI 0.31-0.58; P < 0.001) and live birth (aOR 0.53, 95% CI 0.37-0.76; P < 0.001) were observed. These findings indicate that the presence of unicornuate uterus is associated with significantly increased risk of some adverse pregnancy outcomes compared with pregnancies with a normal uterus in women who undergo IVF-ET.