Common Myths of Pregnancy

When I was pregnant with my first daughter, I went to see the woman who had been described to me as the best OBGYN in San Francisco, Dr. Laurie Green. It seems that most people I know who have had a baby in San Francisco has gone to Dr. Green. Even so, through my two pregnancies, I have never felt that she was too busy for me. She always listened patiently to all of my questions and provided very straightforward and pragmatic answers. She often backed up her answers with supporting articles and documents, something my research-focused brain greatly appreciated. One article that stuck in my memory was about common myths of pregnancy. So while putting together this newsletter, I asked if I could share with you that list of myths. It's from a book by Michael Benson called Obstetrical Pearls. Here are a few of the most interesting myths:

Myth #1: Pregnant women should not sleep on their backs.

A particular persistent myth, its origins can probably be traced to the observation that labor in the supine position can compromise uterine blood flow. This is not relevant to non-laboring patients (and not terribly important for those in labor). Although many women are uncomfortable flat on their back and can even develop symptomatic hypotension, those who can tolerate this position will not cause fetal injury. (Those who cannot will simply avoid the position naturally.)

Myth #2: Hot baths can injure the fetus.

Although some data do link increase in maternal core temperatures with birth defects, it is nearly impossible to raise core body temperature from a hot bath. Total body immersion in warm water may raise body temperature, but as a practical matter, studies of this issue have found that people become very uncomfortable with rise of a single degree in their core temperature. Because significant increases in core heat can result in unconsciousness, the general precautions regarding body immersion in whirlpools also apply to pregnant women. Limit total time, and get out if dizziness or discomfort occurs.

Myth #3: The fetal heart rate is linked to gender.

The heart rate varies from instant to instant, so this idea falls apart under the briefest scrutiny.

Myth #4: Women are more likely to into labor during a full moon.

Scientifically studied, this is not true.