Summer heat increases risk of amniotic fluid level deficiency, study reveals

July 30, 2009

Pregnant women have a higher incidence of insufficient amniotic fluid levels (oligohydramnios) in the summer months due to dehydration, according to a study conducted by researchers at Ben-Gurion University of the Negev (BGU).

The retrospective population-based study was published in the July issue of Archives of Gynecology and Obstetrics. The main objective of the study was to determine whether the summer season is a risk factor for oligohydramnios, by comparing the frequency of amniotic fluid loss during the summer months versus its frequency during the rest of the year.

In the study at Soroka University Medical Center in Beer-Sheva, Israel, the researchers evaluated pregnancies of patients with oligohydramnios that delivered from May to August during the years 1988-2007.

After excluding other causes of fluid loss, such as premature rupture of membranes, intra-uterine growth restriction or malformations, the study determined that higher rates of oligohydramnios were found in the summer months as compared to the rest of the year.

During the study period, there were 191,558 deliveries of which 4,335 were diagnosed with idiopathic oligohydramnios. Of these, a proportionally higher number, 1,553 deliveries (36 percent), occurred during these four summer months, while 2,782 deliveries occurred during the other eight months of the year (64 percent).

"It is important for pregnant women to drink appropriate amounts of water specifically in the summer -- about 10 glasses per day -- and avoid direct sun, not only for the health of the mother, but also in order to avoid fetal dehydration," explains Prof. Eyal Sheiner of the Faculty of Health and Sciences at Ben-Gurion University of the Negev.

Amniotic fluid is the nourishing and protecting liquid contained by the amnion of a pregnant woman. It protects the developing baby by cushioning the mother's abdomen, promotes muscular and skeletal development, and helps to protect the fetus from heat loss.

More information: "Is Oligohydramnios More Common During the Summer Season?" Archives of Gynecology and Obstetrics 280.1 (2009): 3-6.

Source: American Associates, Ben-Gurion University of the Negev (news : web)