Photo: Tim Clayton/Corbis

Just in time for Meaghan O’Connell’s extremely good (and extremely difficult to read) account of getting an epidural comes a new study in Psychological Science on the question of how women remember their experiences of giving birth. According to a popular theory, the press release explains, when it comes to remembering experiences “we tend to recall the moment of peak intensity and the final moments, which we average and use to form an overall memory of the experience … [while] the duration of an experience is not all that important to memories — a phenomenon called ‘duration neglect.’” The authors of the study wanted to know whether this applies to childbirth as well.

So they dispatched researchers to sit with more than 300 women at an Israeli hospital and ask them to rate their pain every 20 minutes. They then followed up with the women two days and two months after they gave birth to ask them to rate the overall painfulness of the experience.

Here’s what they found:

The women’s recollections of pain, at two days and two months after birth, were skewed by just two moments of the 6 ½ hour experience, the moment of peak intensity and the moment of birth. These two moments of pain were a better predictor of pain memories than was the average of all pain ratings. In contrast, the duration of each mother’s experience played little role in shaping memories of the event. The scientists compared first-time mothers with experienced mothers, with interesting results. The peak-end rule was not as good a predictor of long-term pain memories for mothers who had given birth previously. This suggests that experience and previous knowledge can dilute the effect of the peak-end bias over time, even with such a unique and rare experience as childbirth.

In other words, all things being equal, a really short labor with a couple of moments of terrible pain will be remembered as more arduous than a very, very long labor with only moderate pain.

The science of how people perceive pleasant and unpleasant events and subsequently remember them is really tricky, of course — there’s no such thing as an “objective” measurement of pleasure or pain. But studies like this can help us plan events in a way to maximize our pleasurable (or minimize our painful) memories.

For example, one psychologist — I can’t remember who — said that whenever he plans a family vacation, he makes sure the very last bit of it is as relaxing as possible, since he knows that given how long-term memories are formed, if the final few hours are a frantic, stressful race to the airport, that will drape the entire vacation in a negative light. It’s a helpful tip, even if it won’t be much use to a woman in the throes of labor.