Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Delay in cutting the cord helps premature babies

18.10.2004


Waiting 30 seconds to two minutes after birth to cut the umbilical cord of a premature baby appears to lessen chances of bleeding in the newborn’s brain and reduce the need for transfusions, according to a new review of research.

Standard practice for preterm babies is to cut the cord as soon as possible, often within 10 to 15 seconds. A systematic review finds that delaying the clamping rather than doing it immediately also reduces anemia and increases blood pressure and blood volume, helping preterm infants off to a healthier start in life, says lead study author Heike Rabe, M.D., Ph.D. of Brighton and Sussex University Hospitals in Brighton, England. "If the cord is left unclamped for a short time after the birth, some of the baby’s blood from the placenta passes to the baby to help the flow of blood to the baby’s lungs," Rabe explains. "Delaying cord clamping for just a very short time helped the babies to adjust to their new surroundings better."

The review appears in the October issue of the Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.



Medical staff ordinarily clamp the umbilical cord in two places after the baby is delivered, then cut the cord between the two clamps. "I’m comfortable with the 30-second delay, but there are so many things that can happen with a preterm infant that doctors have to use their judgment in each case," says neonatologist Tonse N. K. Raju, M.D., D.C.H., of the National Institute of Child Health and Development in Bethesda, Md. The seven studies in Rabe’s systematic review covered 297 infants. The studies measured blood pressure, red blood cell counts, blood volume, bleeding within the brain and the need for transfusions.

Since 60 percent to 80 percent of preterm infants less than 32 completed weeks’ gestation require transfusion, strategies that might reduce this without risk would be desirable, says Rabe. Decreasing the need for transfusion would be especially valuable in developing countries, where transfusion carries a high risk of transmitting infection.

No formal guidelines currently set the time for clamping the cord. The American College of Obstetricians and Gynecologists says it does not take a position on the timing of cord clamping, citing "insufficient evidence." However, pre-term infants (those born at 24 to 37 weeks) often have trouble breathing, so physicians prefer moving them immediately to intensive care units where they are helped to breathe. Moving the baby requires clamping and cutting the umbilical cord quickly. "The acceptable range of red blood cell levels or blood pressure in preterm infants is so narrow that even seconds can make an important difference," Raju says. Despite this importance, evidence is sparse. "Clamping time is seen as so unimportant that it’s not even recorded on hospital charts, which makes it hard to do even retrospective studies," says Judith Mercer, C.N.M., D.N.Sc., of the University of Rhode Island, who has studied the issue.

Despite concerns for the baby’s respiratory status, the trials covered in the review offered little guidance about how breathing is affected by cord clamping time, Rabe says. "At least there was no negative effect on babies’ breathing after delaying the clamping of the cord." Practices vary with who is delivering the baby and where, says Mercer. "In the United States, it’s more common to cut the cord immediately, while in Europe it’s more common to delay." Nurse-midwives favor delaying, compared to physicians, she says. They prefer clamping at between one and three minutes (35 percent) or even later (33 percent), she found after surveying 303 midwives.

Arguments exist for both early and delayed clamping. Clamping too soon prevents blood from returning through the umbilical cord to the baby’s body. "A little extra blood can help restore blood pressure," says Raju. Low blood pressure may require transfusions of blood or fluids, which can be tricky to accomplish safely in a preterm baby.

On the other hand, delaying clamping too long can actually pack too many red blood cells into the baby’s system. That can make the blood too thick, stressing the heart and respiration, and possibly triggering jaundice or brain damage. Such a delay may also prevent adequate resuscitation or unnecessarily expose the baby to cold. Mercer notes that few long-term studies have examined what happens to these babies as they grow up.

She is conducting a randomized controlled trial funded by the National Institutes of Health of early versus later clamping times in 74 preterm babies. In this study, the infants will be followed until they are 7 months old when developmental testing will be done. Eventually, she hopes to track them up to age 5. Although the study is not complete, she says that the data safety checks show no harm from a delay of 30 to 45 seconds at birth.

While expectant mothers should not have to think about the details of cord-clamping time, physicians and midwives should familiarize themselves with the review’s conclusions, Raju says. The Cochrane Collaboration has a systematic review of cord-clamping times in full-term infants in process and plans to publish it soon.

Heike Rabe | EurekAlert!
Further information:
http://www.bsuh.nhs.uk

More articles from Health and Medicine:

nachricht Using fragment-based approaches to discover new antibiotics
21.06.2018 | SLAS (Society for Laboratory Automation and Screening)

nachricht Scientists learn more about how gene linked to autism affects brain
19.06.2018 | Cincinnati Children's Hospital Medical Center

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Graphene assembled film shows higher thermal conductivity than graphite film

22.06.2018 | Materials Sciences

Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle

22.06.2018 | Earth Sciences

Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View

22.06.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>