Fetal Survival Improving in Norway

NEW YORK (Reuters Health) Jan 19 - Fetal death rates have dropped considerably in recent decades, Norwegian researchers report in a December 23rd online paper in BJOG.

As Dr. Aahshi A. Sarfraz told Reuters Health by email, "Fetal mortality rates have decreased substantially over the last forty years, in particular fetal deaths at term. We believe the reduction of fetal deaths in term pregnancies can be explained by improved antenatal and obstetric care."

Dr. Sarfraz of Akershus University Hospital, Lorenskog, and colleagues studied national data on the more than 2.18 million pregnancies with births after at least 16 weeks' gestation. The period covered was 1967 to 2006.

In all pregnancies lasting longer than 22 weeks, the fetal death rate decreased. In term pregnancies (37 to 43 weeks) the drop was from 10.8 to 3.3 fetal deaths per 1000 at risk.

For those of 30 to 36 weeks, the rate declined from 4.5 to 1.1 per 1000. The corresponding drop at 23 to 29 weeks was from 2.8 to 1.3 per 1000.

However, there was an increase in mortality in early gestation (16 to 22 weeks). The figure rose from 1.7 to 3.4 fetal deaths per 1000 ongoing pregnancies. This remained the case after adjustments for factors including maternal and paternal age and parity.

The overall improvement, continued Dr. Sarfraz, "may have been facilitated by introduction of modern technology in the 1980s, to estimate pregnancy duration and to diagnose fetal distress. In a public health care setting, as in Norway, such technology is routinely used in all pregnancies."

"The increase in fetal deaths in very early pregnancy is more difficult to explain. Our study reveals a possible new trend, and we hope future research will provide explanations so that also these very early fetal deaths may be prevented." he added.

One possible cause, the researchers conclude, is "an increase in early delivery caused by the increased proportion of women being treated with cervical cone excision before pregnancy."