Failing to get a good night’s sleep may make it harder to have a baby, research shows.

London - Failing to get a good night’s sleep may make it harder to have a baby, research shows.

Researchers from the Hanabusa clinic in Kobe, Japan, asked 208 women who were having problems getting pregnant to fill in a survey known as the Pittsburgh Sleep Quality index.

This assesses factors including how long they slept for, whether they woke up in the night, their disturbances, use of sleeping pills, their subjective sleep quality and how much alcohol they drank.

Based on the results, the patients were divided into three groups: no sleep difficulties (65 percent), mild difficulties (26.8 percent) and severe difficulties (8.2 percent).

The chance of eggs fertilised in the laboratory successfully growing into embryos was then assessed. The eggs of women with no sleep problems were successfully fertilised 62.9 percent of the time, falling to 57.1 percent in those with mild sleep difficulties, and 48.4 percent in patients with severe difficulties.

The researchers said: "Good sleep patterns can be one of the important daily habits for patients to improve their response to fertility treatments and increase their chances of pregnancy."

Occasional or moderate alcohol consumption had a positive impact on fertilisation, they found. This may be due to the beneficial effects of a moderate amount of alcohol, such as relieving stress and inducing sleep.

Professor Matthew Walker, of the Sleep Research Centre at Berkeley University in California, who was not involved in the study, said the findings were consistent with other research.

He said: "For example, women sleeping less than six hours per night suffer a 20 percent reduction in a follicular-releasing hormone – a critical female reproductive element that peaks just prior to ovulation and is necessary for conception."