For a study, researchers sought to determine if the placenta accreta spectrum developed more commonly in twin pregnancies than in singleton pregnancies. From 2016 to 2017, all live births were tracked down using previously connected records of birth certificates and hospitalization discharges. The placenta accreta spectrum (which encompasses placenta accreta, increta, and percreta) was discovered using the International Classification of Diseases, Tenth Revision, Clinical Modification codes (O43.2x) for placenta accreta, increta, and percreta as the major result. Researchers used multivariable logistic regression to investigate the link between twin gestation and placenta accreta spectrum, and they used a previously validated International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)–based technique to see if the findings were repeated.

The Placenta accreta spectrum was identified in 1,126 of 918,452 live births. The placenta accreta spectrum was found in 11.8 out of 10,000 singleton births and 41.6 out of 10,000 twin pregnancies. Twin pregnancy was linked to a greater relative risk of placenta accreta spectrum in the unadjusted regression analysis (RR 3.41, 95% CI 2.57–4.52). The link with an increased relative risk of placenta accreta spectrum remained after correcting the regression model for maternal age, prior cesarean delivery, and sociodemographic variables (aRR 2.96, 95% CI 2.23–3.93). Women with twin gestations were less likely to have placenta previa than women with singleton gestations with placenta accreta spectrum. The placenta accreta spectrum was shown to be more common in twins than in singletons when analyzed using ICD-9-CM codes, with an increase in the relative risk of the placenta accreta spectrum (aRR 2.45, 95% CI 2.33–3.25).

Independent of assessed risk variables, twin gestation was associated with an elevated risk of placenta accreta spectrum, which led to greater maternal morbidity in twin gestation compared to singleton gestation. Clinicians should be aware of the elevated risk of the placenta accreta spectrum in twin pregnancies and factor it into their ultrasonographic screening.