The woman, who is in her 20s, remains hospitalized in extremely critical condition Wednesday morning, police said.
Police were called to a home in the 600-block of West Nippersink Road around 2 p.m. where officers discovered a pregnant woman wounded in the head.
Police announced charges against Alvin L. Quinn, 30, of Zion Wednesday afternoon. Police said Quinn used to live at the residence where the shooting occurred and is married to the victim. Police said the couple drove to the home on Nippersink Road to retrieve property they left behind after moving.
When they arrived, police said Quinn - who was armed with a gun - got into an argument with someone inside the residence. During the argument, police said Quinn pulled out his gun and there was a struggle over the firearm. Police said the gun went off during the struggle and struck Quinn's wife in the head.
Quinn is charged with one count of Involuntary Manslaughter of a Child and one count of Reckless Discharge of a Firearm. Police said additional charges are likely.
Quinn is due in court Thursday morning.
The shooting left neighbors shaken.
"I moved to here because the town is quiet, and now it's scary," said Joel Garcia, Round Lake resident.
Police said there is no ongoing threat to the community.