(Reuters Health) – Among pregnant women at high risk of preterm birth, those who eat fish a few times a week may be less likely to deliver early, a new study finds.
Whether fish itself helps prevent preterm delivery is not clear, the researchers stress. But, they say, the finding is in line with the general advice that pregnant women eat up to two fish meals per week.
The study, reported in the journal Obstetrics & Gynecology, included 852 pregnant women who were at higher than average risk of preterm delivery because they had delivered early before.
Overall, 70 percent said they had averaged at least a half-serving of fish per week during the first 4 to 5 months of pregnancy. Of those women, 36 percent went on to have a preterm birth.
In contrast, that rate was 49 percent among women who ate fish no more than once a month.
In general, the researchers found, women who ate two or three servings of fish per week were about 40 percent less likely to deliver early than women who ate fish less than monthly.
There was no evidence, however, that a higher fish intake was related to any further cuts in preterm-birth risk.
“It wasn’t that the more fish you ate, the better,” said lead researcher Dr. Mark A. Klebanoff, of Nationwide Children’s Hospital in Columbus, Ohio.
In fact, he said, the benefit may not come from fish at all.
The researchers tried to account for factors that could make fish-eaters different from other women — like their weight, race, education levels and smoking habits.