Jay Leonard Rodriguez, 49, was detained on Saturday and charged with two counts of second-degree murder in the deaths of the woman and the baby. The name of the woman has not been released in court documents.
On Monday, prosecutors in the case filed a motion to have Rodriguez held in jail without bail until the trial.
Included in the motion and the arrest report was a witness account from Jessica Gonzalez, a woman who tried to help the pregnant woman and was also threatened by Rodriguez.