(Ivanhoe Newswire) -- Fetal death, or intrauterine fetal demise (IUFD),
caused by an under-sized placenta, affects 30,000 women in the U.S. each
year.
Technological limits currently prevent doctors from monitoring the growth of
the placenta, the source of nourishment for the fetus. “The placenta can be
so small that the fetus literally runs out of food and oxygen and dies,”
lead author Harvey J. Kliman, M.D., a research scientist in the Yale
University Medical School Department of Obstetrics, Gynecology and
Reproductive Sciences was quoted as saying.
Kliman noted that many late-term pregnancy losses were associated with very
small placentas. He theorized that the growth of the placenta could be
monitored in much the same way an obstetrician uses ultrasound to follow the
growth of the fetus.
When Kliman asked perinatologists why they did not measure the placenta when
performing routine ultrasounds, the answer was always the same: the placenta
is a curved structure and is too difficult to measure. Measuring placental
volume would require very expensive machinery, specialized training and more
time.
With the help of his father, mathematician and electrical engineer Merwin
Kliman, Harvey Kliman developed an equation to compute the maximal width,
height and thickness of the placenta. Kliman and his team then validated the
method by comparing the volume predicted by the Estimated Placenta Volume (EPV)
equation taken just before delivery to the actual weight of the placenta at
the time of delivery.
“In this study, we showed that the equation predicted the actual placental
weight with an accuracy of up to 89 percent,” said Kliman. “The method works
best during the second and early third trimesters, just when routine
ultrasound screening is done on many women in the U.S.”
In addition to validating the equation, the team is also collecting EPV data
from centers around the world to create normative curves doctors can use to
determine if the placenta is normal, too small or even too big. Kliman
expressed his hope that “. . . the EPV test becomes routine for pregnant
women.”
SOURCE: American Journal of Perinatology, August 3, 2009
