Pregnant women are advised to be cautious of many things — sushi, Brie, hot tubs and kitty litter, to name a few — but I was surprised to receive a concerned phone call warning me about the dangers of an eclipse when I was expecting my first child.

Don’t use a pair of scissors or a knife during an eclipse, my mother said, or the baby could be born with facial birth defects. Unlike the risks posed by uncooked fish or soft cheese, there is no scientific or medical basis for this sort of alarm. But there are persistent superstitions and myths surrounding celestial events as dramatic as a solar eclipse, which much of the St. Louis region will experience Aug. 21.

In many cultures, including my parent’s South Asian background, pregnant women are told to stay indoors during an eclipse to prevent birth defects. The parenting advice website BabyCenter, in a section on traditional Hispanic beliefs and myths about pregnancy, also notes that an expectant mother is told to carry something metallic, such as a safety pin, during an eclipse to protect against cleft palate.

The site suggests the superstition traces back to an Aztec belief that an eclipse is a bite on the face of the moon.

David Baron, author of “American Eclipse,” says that there was a time in the 1970s that the Indonesian government advised pregnant women to stay indoors during a solar eclipse. (That’s no longer the case.)

“There’s nothing to fear but epic traffic,” he said about the cars expected to crowd highways to get a good view when the solar eclipse passes over an area.

The editorial team of BabyCenter India posted a list of common restrictions and beliefs aimed at keeping a pregnant woman safe during an eclipse:

• Not using any sharp object such as a knife, scissors or a needle for the duration of the eclipse.

• Not eating anything for the duration of the eclipse.

• Resting as much as possible during the eclipse.

• Covering the windows with newspaper or thick curtains so that no rays of the eclipse enter the home.

• Throwing away all cooked food from before the eclipse.

Get tips on free stuff and fun ideas delivered weekly to your inbox

• Taking a bath after the eclipse is over.

The article noted that there is no evidence to suggest an eclipse is harmful to a pregnant woman or her baby and also listed the dangers of pregnant women fasting during an eclipse, which is also a common practice in parts of India.

Dr. Shafia Bhutto, an obstetrician-gynecologist at Mercy Hospital in St. Louis, says expectant women in Pakistan might be told to lie straight in bed during an eclipse to prevent crooked joints in a baby.

“There’s nothing real about that,” she said. Her only medical advice applies to everyone: Don’t look at the sun directly because it can damage your retina.

“There is nothing that will happen to your unborn baby during an eclipse because they are in your uterus,” she said.

But superstitions are hard to shake. Bhutto remembers a woman from many years ago who was distraught throughout her pregnancy because she accidentally looked at a lunar eclipse. That woman’s baby was born with a cleft palate that was never picked up in the ultrasounds.

“Even though it was completely unrelated, the patient totally blamed herself,” she said.

Aisha Sultan • 314-340-8300

Home and family editor

@aishas on Twitter

asultan@post-dispatch.com