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There’s a lot of mystique around the moon and how it affects humans — particularly pregnant humans.

You may have even heard that the full moon can trigger labor if you’re nearing your due date. After all, the gravitational pull of the moon is strong enough to shift ocean tides. It might also impact amniotic fluid, or so the story goes.

Here’s how to separate fact from fiction with this popular belief as well as what other natural forces might lead to early labor or delivery.

As you might suspect, there’s not a lot of study on the so-called lunar effect on pregnancy. In fact, the moon triggering labor falls better into the category of oral tradition than science.

In a 2005 survey of just over 100 people at an obstetric clinic in the Midwest, researchers discovered that around 60 percent of people had never heard about the moon influencing pregnancy and birth.

So, if you haven’t heard of this phenomenon, you’re not alone. Around 11 percent of those surveyed, though, did believe that a full moon could trigger labor.

Perhaps even more interesting is that another survey (reported in the same journal article) among medical staff produced the opposite result. Some 26 out of 38 nurses — roughly 70 percent — on the delivery floor said that labor was more likely to be triggered by a full moon. All nurses on the floor had at least heard of this idea, whether they agreed or disagreed.

Despite these anecdotal accounts, there’s not much hard data to support the moon having any influence on pregnancy or labor.

In one dedicated study on the matter (again, from 2005), researchers examined 564,039 births that happened over 62 different lunar cycles in North Carolina between 1997 and 2001.

The results were somewhat underwhelming, if you’re team full moon.

The study looked at things like the frequency of births, method of delivery, and pregnancy complications throughout all eight phases of the moon. No significant associations were found between the lunar cycle and births (for example, more women having babies during a full moon) or pregnancy complications over the 5-year period.

In the end, the researchers concluded that the lunar effect on labor is merely a “pervasive myth” lacking evidence to back it up.

On the other hand, a newer (but smaller) study found that over the course of a year at one facility and 8395 births, deliveries increased during the full moon by 14.7 percent.

Weather patterns are another force some believe may influence labor and delivery. Unlike moon cycles, there’s some data suggesting that barometric pressure changes with weather systems may actually have some impact on labor.

In one study from 2007, low barometric pressure was associated with the rupture of membranes (water breaking) and premature labor. You might see low pressure with hurricanes, blizzards, or other storms. A large change in barometric pressure — high to low, low to high — was also linked to an increase in births.

Other experts theorize that the influence weather systems have on pregnancy may be more psychological in nature. For example, you may feel anxious during or after a large storm or natural disaster like a hurricane. The added stress may lead to preterm labor or delivery.

The end of pregnancy can feel long and uncomfortable. You may be trying anything and everything to get your baby out and into your arms. But the full moon likely won’t help.

The good news is that you’re getting closer to meeting your baby with each passing day, regardless of where you find yourself in the lunar cycle.

If you’re feeling particularly impatient and have your doctor’s OK, you might consider trying other natural techniques to jumpstart your labor if you’re at least 39 weeks along.

For example, stimulating your nipples may produce oxytocin in the body and lead to uterine contractions. Exercising, having sex, and eating dates may also move things along, but be sure to chat with your doctor before overdoing it on any home methods.

As you approach your due date, you may have weekly or even more frequent prenatal appointments. Use them as an opportunity to ask questions or air concerns.

Your obstetrician or midwife can give you some clues for how things are going with you and baby, such as sharing how dilated you are or performing a nonstress test.

Beyond that, it’s a waiting game — but don’t put your trust in the moon.