There is a curious pattern I have noticed, though it has no solid statistical foundation behind it. So it cannot be used to say, with any confidence, how often it happens or how much weight it deserves.
The question is simple enough: when is cheating most likely to happen? But the question itself is almost useless to society. Worse, it can easily deepen suspicion between two people in a relationship. It works a bit like those so-called relationship tests: if the other person gives the “wrong” answer, does that prove they will betray you? And if they pass every test perfectly, does that guarantee they will never cheat?
The more unserious a topic sounds on the surface, the more seriously it should be handled.

The interesting common thread I found, within a limited number of cases, is not a particular personality type, nor a fixed moral category, but a timing issue.
Search for phrases like “cheated that night,” and you will find that “that night” seems to carry a strange dramatic force: the night a wife gives birth, the wedding night, the night a couple reconciles after a huge fight, and so on.
In many real cases, after an intense argument, women appear more inclined to seek comfort through another intimate connection. This part is not especially difficult to understand. One of the fastest, and sometimes most effective, ways to soothe the pain created by a relationship is to use another relationship as emotional compensation. This becomes even more likely when there has already been a “comparison object” in the person’s emotional life. Whatever their partner does can be measured against this other person: good enough, not good enough, caring enough, not caring enough. The sharper the comparison, the easier it becomes for the hurt person to imagine that receiving affection from the other side can repair the wound.
The other side is harder to grasp. For example: the night his wife gives birth, a husband cheats with his first love. One can roughly reconstruct the twisted logic of such a man: “Starting tomorrow, I’ll be a father. I need to cut ties with my past, and having sex one last time is the best way to draw a clear line between my first love and me.” Or perhaps: “Tomorrow I stop being merely a husband and become a father. Tonight I need to grow up, so I’ll give myself one last ‘single night.’ In some absurd way, this proves I’m taking responsibility.”
There was also a particularly ridiculous real case: a couple went downstairs to eat barbecue after making peace following an argument. The boyfriend said he was going out to buy cigarettes. During that short interval, he was detained for soliciting prostitution. Before going to the police station, the girlfriend still suspected the police must have caught the wrong person—after all, the two of them had just reconciled and gone out for food together.
But the point here is not to discuss “the causes of cheating.” People who cheat often refuse to admit the real motive; and almost any supposed cause can be redefined through self-persuasion, evasive reasoning, or outright sophistry. What stands out across many cases is this: cheating often seems to occur when a relationship is entering its next “stage.” That may be pregnancy or childbirth, a couple returning to normal after a severe fight, or the moment when long-term pressure finally disappears. This “stage change” is not limited to the relationship between two people. It can also be a psychological or physical transition within one person.
That is why this kind of “research” has no real practical value. We should not avoid changes in a relationship just to prevent cheating. Nor should we try to block the natural psychological or physical shifts a person may experience. Even more sadly, if those changes were somehow prevented, would cheating disappear? Of course not. People who want to cheat would simply develop new reasons and new methods.
A direct example makes the problem clearer.
After Li Yifeng was detained for soliciting prostitution, some people produced a very “logical” reverse inference: My God, even male celebrities solicit prostitutes—Li Yundi, Li Yifeng. Then what about ordinary men?
Anyone with even a little sense of logic can see the problem. This is a classic combination of the slippery slope fallacy and hasty generalization. A may lead to B, B may lead to C, and C may lead to D; each step may have some probability of occurring. But slippery-slope reasoning erases all those probabilities in the middle, ignores the strength of causal links, and treats A as if it must inevitably produce D. At the same time, hasty generalization takes one man’s betrayal and spreads it over all men.
This is why the argument feels so emotionally powerful to many people: Yes, if male celebrities cheat, then ordinary men must be cheating hundreds or thousands of times more.
Once special cases are discussed without probability or causal strength, the conversation inevitably falls into the trap of slippery-slope thinking. If someone says men are likely to cheat while their partners are pregnant, people will naturally focus only on examples that confirm the claim. Then the statement quietly shifts from “some men do this” to “men will inevitably do this during pregnancy.”
Then the pregnancy period is abstracted even further into “certain special periods” in a heterosexual relationship: times when sex is not possible, or when the woman’s emotions are unstable during pregnancy, and so on. From there, the argument becomes even more dangerous. By reversing the slippery slope, the supposed cause of male cheating is thrown back onto the woman: she could not provide “sexual service,” or she was emotionally out of control because of pregnancy, so the man escaped through cheating.
This is how careless reasoning turns into gender hostility. Follow this so-called “research” to its extreme, and sooner or later it becomes an uncontrollable war between men and women.
Still, if we set aside the slippery-slope logic people often use, the claim remains strangely tempting. If someone tells you, “People in relationships are most likely to cheat when the relationship is entering a new stage,” you probably will not fully believe it. Yet you may still be drawn to the examples. The reason is simple: once a conclusion like this is offered, proving that it does not exist is far harder than proving that it does.
A few days ago, I encountered someone who refused to allow others to recommend a product he disliked, because he had personally run into problems while using it. I asked him under what conditions the problem appeared. Since I had not experienced it myself, I could not evaluate it without knowing how to reproduce it. Only if he could explain the conditions could I judge whether the “problem” truly existed in a meaningful way.
This is the difficulty of “proving that the devil does not exist.” Proving nonexistence is extremely hard, because as soon as someone produces one example of the devil’s existence, the claim that the devil does not exist collapses. By comparison, proving existence becomes much easier.
The person who opposed the product recommendation did not appreciate this. Instead, he felt that asking for reproduction conditions was an attack on the difficulty he had encountered. His answer was basically: “I experienced it, so I experienced it. I don’t need to prove anything to you.”
Now imagine I put forward a provocative new thesis: men are likely to cheat during the period when a relationship moves from conflict back into reconciliation. Some people will certainly stand up and deny it. But I can also produce a pile of cases showing that some men did cheat when their wives were pregnant, giving birth, or immediately after a major fight had just been resolved.
At that point, how should you refute me?
A hint: sometimes, the only thing that can defeat magic is magic.