She said they want to "wait until Vaeda is a little older, like, 6 months to a year," before they try to get pregnant again.
In addition to Vaeda, Lowell and Baltierra, 27, are also parents to daughter Novalee, 4. They placed their first daughter, Carly, now 9, for an adoption in 2009.
Lowell suffered a miscarriage in 2017 and said they weren't expecting to get pregnant with Vaeda.
“This baby is our rainbow after the storm,” she told the magazine last year. “We were using protection and everything. This baby just wanted to be here. It was very unexpected.”
Lowell and Baltierra initially announced that they were going to name their new bundle of joy Tezlee, but ultimately decided against it.
"Every time someone would say Tezlee, we would bring! It just wasn't sitting with us like it did at first," the MTV star said. "Tyler told me about the name Vaeda and I fell in love with it! It's from the movie My Girl, which is a movie that Tyler showed me years ago."
The character Vada, spelled without the "E," was played by Anna Chlumsky in the 1991 film.
Earlier this month, after Vaeda's arrival in February, Lowell told Us Weekly that Vaeda is "such a good baby — very chill and easy going... so far."
Lowell suffered from postpartum depression after giving birth to Nova in 2015, but worked with a psychologist who specializes in trauma during her third pregnancy.
“I’m not anxious. I’m not depressed,” Lowell said in September 2018. “I’m actually in a good mental state with this [pregnancy].”
But toward the middle of Lowell's pregnancy, the couple announced that they were taking a bit of a break.
"Am I jumping for joy for it? No. Things that I've been through, when when people separate and say they want to leave, it seriously feels like somebody died. It’s bringing up the old wounds from the miscarriage, and that's traumatic," Lowell said during an episode of Teen Mom OG.0comments
"I think me and Cate got together super young, and we used each other as survival to drive through this life," Baltierra added later, speaking about the split on the Teen Mom OG season 8 reunion. "You just kind of lose who you are as an individual. Who am I if I'm not Catelynn's husband?”
But as of late, the two appear to have reunited in the midst of their newest child's arrival.