With Khloé and Tristan making headlines, we sought insight from a relationship expert.

Anthea Levi
April 12, 2018

Today in Kardashian news: Khloé gave birth to her baby girl this morning. But earlier this week, a troubling story swept the internet: Boyfriend and baby daddy Tristan Thompson allegedly cheated on Khloé during her pregnancy. The allegations arose after Thompson was seen getting close to another woman while partying in New York City over the weekend.

There's still no confirmation that the Cleveland Cavaliers player did cheat on Khloé. But the gossip spiral got us thinking. How common is it for people to cheat on their pregnant partners? And what would drive someone to do something so terrible at such a vulnerable time in a woman's life?

“You would think it would be the opposite, but the third trimester seems to be challenging for a lot of partners, and they may step outside the bounds of the relationship at this time,” says Holly Richmond, PhD, a Los Angeles–based sex and relationship therapist. Richmond tells Health that she's seen this happen with at least half a dozen of her clients.

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But why? One explanation is that a couple's sex life might change when a baby on the way. It’s not a very common reason, but if a woman is having health complications (the positioning of the baby is off, for example, or she’s bleeding), her doctor may advise against penis-in-vagina sex.

“Some women just feel sick for the whole nine months, and if you’re throwing up, you’re probably not going to feel super sexy,” says Richmond. A woman’s size during her third trimester may also make her less inclined to get it on, either because she's uncomfortable or doesn't feel attractive. If a lengthy dry spell ensues, there's potentially a greater risk of cheating by her partner (insert eye roll).

But a change in a couple's sex life is not the most common reason partners may be likely to stray when their wife or girlfriend is having a baby. Instead, it's cold feet about the next phase of life that tends to prompt some two-timing.

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“A man might feel like, ‘Oh my gosh, I’m about to become a father, I’m about to take on a huge responsibility, Can I do it? I’m scared,’” says Richmond. “A lot of it has to do with self-doubt and insecurity, but it’s also about losing his independence and sense of autonomy.”

According to Richmond, third trimester cheaters typically hook up with people they know, not strangers. “I’d say about 80% of the time, they already know the woman they’re cheating with. A lot of times there has been a relationship there, and even if it wasn’t sexual in the past, it then explodes into this sexual thing late in their partner’s pregnancy.”

In general, though, it’s highly uncommon for a significant other to cheat on a pregnant partner, and not every duo will encounter these challenges. Couples often become even closer at this time, and in fact, the majority of women actually enjoy sex more when they’re expecting.

“Most women I see that are pregnant are horny, they want that connection with their partner, and they’re loving their body, feel so womanly, and want to be in touch with everything sensual and sexual,” says Richmond. “To be honest, I typically see an uptick in sex among couples during pregnancy.” Now that’s something to look forward to.