Miscarriage rates following IVF appear to increase when the clocks go forward in the spring, according to a study.
The results were particularly marked among patients who had suffered a previous pregnancy loss, but no change was noted when the clocks were turned back in the autumn.
'To our knowledge, there are no other studies looking at the effects of daylight savings time and fertility outcomes,' said Dr Constance Liu of the department of obstetrics and gynaecology at Massachusetts General Hospital.
'We knew that we were researching an uncharted field, and it was important for us to understand the effect a one-hour change had on patients undergoing IVF,' she added.
The study looked at 1654 cycles of IVF from 2009 to 2012. Miscarriage rates were similar across the seasons – 15.5 percent in the spring and 17.1 percent in the autumn.
But the rates jumped when embryo transfers were carried out 21 days after Daylight Savings Time (DST) to 24.3 percent. Among women who had previously had a miscarriage, the rate soared to 60.5 percent.
The health effects of DST have been noted in other areas – the one-hour time difference has been linked to an increase in heart attacks. It is thought that it is caused by the disruption of the circadian rhythm, which governs our biological clocks.
'While our findings on the impact of DST on pregnancy loss among IVF pregnancies are intriguing, they need to be replicated in larger IVF cohorts in different parts of the world that observe DST,' said Dr Wendy Kuohung, director of the Division of Reproductive Endocrinology and Infertility at Boston Medical Centre and senior author of the paper.
The study was published in the journal Chronobiology International.