“I’d never really gone through labor ’cause both my babies before were c-sections because of complications with my pregnancies,” says Sims, who gave birth to son Grey Douglas on Jan. 10, in a clip from a video recorded in partnership with Awestruck, a digital network for millennial moms.
“And so I thought, for sure, this was gonna be a c-section, no problem,” continues the actress and model, 43. “You have in your mind, ‘Here’s the date, here’s the plan, it’s gonna be 1-11-17.’ And I know it sounds weird to say that, but as a mom, you just get focused — like lasered in on it.”
Want all the latest pregnancy and birth announcements, plus celebrity mom blogs? Click here to get those and more in the PEOPLE Babies newsletter.
Sims says she and husband Scott Stuber weren’t quite on the same page when Sims first thought she was going into labor in the middle of the night.
“I finally woke my husband about 3:00 and I’m like, ‘I’m not feeling well. My back is hurting, I’m having really bad cramps.’ And he was like, ‘Yeah, yeah,’ ” she recalls. “And I’m like, ‘No no, I’m serious.’ ”
She says she started timing her contractions at 23 minutes, then noticed the intervals were 15 minutes, then 12. At at 4:30 a.m., she finally called her doctor.
“I think my husband knew I was in labor when I went to take a shower … he was like, ‘Okay, game on,’ ” Sims says. “I kept pacing. I’m like, ‘Is this labor? Is this not labor?’ It was very confusing, but I was in so much pain.”
RELATED VIDEO: Molly Sims Expecting Third Child
“She was like, ‘If it gets to nine minutes, go to the hospital,’ ” Sims explains of what her doctor told her over the phone. “Literally, like 10 minutes later, I was at nine minutes apart.”
She continues, “We rushed to call someone to come stay with the kids. I finished packing the bag — I’d had it packed from the video so I had most of it done, but I can’t tell you how stressed I was.”
“I was trying to make my husband go through red lights on Sunset, because we live quite far now from [Cedars-Sinai Medical Center],” she adds. “And we got into an argument because he wouldn’t run a red light because I was having contractions.”
Once Sims and Stuber arrived at the hospital, Grey’s birth was pretty much out of their hands — though Sims did try and get her doctors to agree to her idea that a next-day delivery was the right one.
“I was still trying to convince them that ‘I’m not having this baby until tomorrow, I can hold off,’ ” she says. “Nevertheless, I was in full-on labor.”
Sims goes on to give gratitude to her childbirth team at the hospital. “Thank you, Megan Palermo, for teaching this girl to breathe and knowing what contractions are,” she says. “It was so great. I have to say, I was scared to death … and then when they finally said it was a go, I was like, ‘Oh my gosh.’ ”
For the full video — and how they settled on Grey’s name — tune in to Molly Sims’ YouTube channel Thursday.