Gestational Period Depends on Structure of Placenta:
WEDNESDAY, Nov. 17 (HealthDay News) -- The structure of the
placenta influences the relatively long nine-month pregnancy in
humans, researchers say.
In their study, the investigators found that babies grow twice
as fast in the wombs of some mammals compared to others and that
the difference in growth rate is due to the structure of the
placenta and the way it connects the mother and baby.
The more intimate the connection between the mother and the
fetus, the faster the baby grows and the shorter the pregnancy,
said the researchers at Durham and Reading universities in
Human placentas do not form the complex web-like structure seen
in animals such as dogs and leopards, which helps explain why
humans have longer pregnancies, the study authors explained.
The researchers looked at 109 mammal species and found that the
placenta in some species is "highly folded," resulting in a larger
surface area that increases the rate at which nutrients are passed
from the mother to the baby.
"This study shows that it is not necessarily the contact with maternal blood which determines speed of growth, but the extent to which the tissues of mother and baby are 'interlocked,' or folded, with one another," lead author Dr. Isabella Capellini said in a Durham University news release.
"In humans, the placenta has simple finger-like branches with a relatively limited connection between the mother's tissues and those of the fetus, whereas in leopards, for example, it forms a complex web of interconnections that create a larger surface area for the exchange of nutrients," she explained.
The study findings are published in the current issue of the
The U.S. National Library of Medicine outlines
Copyright © 2010
. All rights reserved.
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.