Health and Fitness News and Notes

Women whose blood pressure is high before they are pregnant may be at increased risk for miscarriage, a new study has found.

Researchers used data from a study of 1,228 women attempting pregnancy after having previously lost a baby. Of the 797 who achieved pregnancy, 188, or almost a quarter, lost the baby again.

The study, in Hypertension, found no association of blood pressure with the ability to get pregnant. But after adjusting for smoking, body mass index, marital status, education, race and other factors, they found that for each 10-point increase in pre-pregnancy diastolic blood pressure — the bottom number in a blood pressure reading — there was a 17 percent increase in the risk of pregnancy loss.

There are many reasons for miscarriage, and often the cause is unknown. But inflammation and blood vessel impairment, which are characteristic of hypertension, are also known to be involved in pregnancy loss.

“Our study is observational and cannot be used to show cause and effect,” said the lead author, Carrie J. Nobles, an epidemiologist with the National Institutes of Health. Still, she pointed out that in addition to its potential effects on pregnancy, high blood pressure can raise the risk for cardiovascular disease. “Maintaining good blood pressure is important even beyond reproductive health,” she said.

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April 20 has become known as a day to celebrate the pleasures of marijuana consumption with parties that traditionally begin at 4:20 p.m.

But a study in JAMA Internal Medicine has found that the high spirits may have a price: a significant increase in fatal car wrecks after the “4/20” party ends.

Researchers used 25 years of data on car crashes in the United States in which at least one person died. They compared the number of fatal accidents between 4:20 p.m. and midnight on April 20 each year with accidents during the same hours one week before and one week after that date.

Before 4:20 p.m. there was no difference between the number of fatalities on April 20 and the number on the nearby dates. But from 4:20 p.m. to midnight, there was a 12 percent increased risk of a fatal car crash on April 20 compared with the control dates. The increased risk was particularly large in drivers 20 and younger.

“These crashes really don’t have to happen,” said the senior author, Dr. Donald A. Redelmeier, a professor of medicine at the University of Toronto. “In the Netherlands, they’ve had legalized marijuana for years, but they have many more interventions — speed cameras, radar, sobriety checkpoints. The roads in the Netherlands are now much safer than those in the U.S.”

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Babies given antibiotics or antacids in infancy may be at increased risk for allergies in childhood.

Researchers retrospectively studied 792,130 infants covered by a health insurance program. Of these, 131,708 received antibiotics, 60,209 got histamine-2 receptor antagonists and 13,687 were given proton pump inhibitors. Both H2 blockers and PPIs are prescribed for gastroesophageal reflex, or GERD.

The study, in JAMA Pediatrics, followed the children for an average of 4 1/2 years. It found that infants given H2 blockers or PPIs were more than twice as likely to have a food allergy as those who were not; the risk was especially high for allergy to cow’s milk. Those given antibiotics were at a 14 percent increased risk for food allergy, a 51 percent increased risk for anaphylaxis (a potentially fatal type of allergic reaction), and more than double the risk for asthma.

The authors suggest that both antacids and antibiotics disrupt the normal intestinal bacteria and that this may explain the association.

“Let’s not prescribe these medicines for things that are very common in babies,” said the senior author, Dr. Cade M. Nylund, an associate professor of pediatrics at the Uniformed Services University. “Just because a baby spits up doesn’t mean that it’s a disease that requires treatment with a PPI. And we have to avoid overprescribing antibiotics for upper respiratory infections and other viral illnesses.”