Both of these uteruses were distinct and almost entirely separate.
Pregnancy with Double Uterus .-- Hollander describes the following anomaly of the uterus which he encountered during the performance of a celiotomy:-- "There were found two uteruses, the posterior one being a normal organ with its adnexa; connected with this uterus was another one, anterior to it.

The two uteruses had a common cervix; the anterior of the two organs had no adnexa, though there were lateral peritoneal ligaments; it had become pregnant." Hollander explains the anomaly by stating that probably the Mullerian ducts or one of them had grown excessively, leading to a folding off of a portion which developed into the anterior uterus.
Other cases of double uterus with pregnancy are mentioned on page 49.
When there is simultaneous pregnancy in each portion of a double uterus a complication of circumstances arises.

Debierre quotes an instance of a woman who bore one child on July 16, 1870, and another on October 31st of the same year, and both at full term.

She had only had three menstrual periods between the confinements.

The question as to whether a case like this would be one of superfetation in a normal uterus, or whether the uterus was double, would immediately arise.