Trying to have a baby? Eating fish might help.

Researchers interviewed 501 couples who were trying to get pregnant without medical assistance. All kept diaries on their diet and other health and behavioral habits, including fish consumption and frequency of sexual intercourse. They followed the pairs for a year or until pregnancy.

They found that men who had two or more 4-ounce servings of fish a week had a 47 percent shorter time to pregnancy, and women a 60 percent shorter time, than those who ate one or fewer servings a week.

Partners who ate fish also had sexual intercourse, on average, 22 percent more frequently, but the association of eating fish with pregnancy persisted even after controlling for frequency of lovemaking.

By 12 months, 92 percent of couples who ate fish twice a week or more were pregnant, compared with 79 percent among those who ate less. The study was published in the Journal of Clinical Endocrinology & Metabolism.

HOW NIGHTTIME TABLET, PHONE USE DISTURBS SLEEP

Bedtime reading with a tablet or smartphone can interfere with a good night’s sleep, some studies and many anecdotal reports suggest. Now researchers have conducted a small experiment to test the idea.

Scientists had nine people spend 10 nights in a sleep laboratory. For five consecutive nights, they read before sleep with an iPad; then they read print for five nights. In both scenarios, they read in a dimly lit room until they felt ready to go to sleep.

The experiment, described in Physiological Reports, found that when people used iPads instead of reading print, they selected a later bedtime and had a later sleep onset. They also had suppressed levels of melatonin, the hormone that regulates sleep, and delayed time to melatonin secretion. Periods of REM sleep — the rapid eye movements of the dreaming stage of sleep — were reduced when they used the iPad rather than printed material.

The volunteers also reported feeling less sleepy in the evening, and less alert in the morning after using the electronic device.