The study was conducted by Dr. William Gibbons, director of The Family Fertility Program at Texas Children's Hospital and professor of obstetrics and gynecology at Baylor College of Medicine, along with colleagues at the Society for Assisted Reproductive Technologies (SART) Marcelle Cedars, MD and Roberta Ness, MD.
They reviewed three years of data that compared average birth weight and gestational time for single births born as a result of standard IVF, IVF with donor eggs and IVF with a surrogate. While the ability to achieve a pregnancy is tied to egg/embryo quality, the obstetrical outcomes of birth weight and length of pregnancy are more significantly tied to the uterine environment that is affected by the reason the woman is infertile.
There were more than 300,000 IVF cycles during the time of the study producing more than 70,000 singleton pregnancies.
"This is the first time that a study demonstrated that the health of a women's uterus is a key determinant for a fetus to obtain normal birth weight and normal length of gestation," said Dr. Gibbons. "While obvious issues of uterine fibroids or conditions that alter the shape of the uterus are suspected to affect pregnancy rates, conditions that result in poorer ovarian function to the point of needing donor eggs are not known. Further research is needed to fully understand this complex issue."
As assisted reproductive technologies (ART) in the U.S. mature, increasing attention is directed not just to pregnancy rates but also to the obstetrical outcomes of those resulting pregnancies – meaning the newborn's birth weight, health and gestational age. Currently, about one percent of U.S. births are the result of ART therapies such as IVF, donor eggs, intracytoplasmic sperm injection, embryo cryopreservation, embryo donation, preimplanation genetic diagnosis, and male infertility surgery and medical therapy.
The study explored several scenarios and found that the birth weight associated with standard IVF – in which the patient carried the embryo created with her own egg – was greater than that associated with donor egg cycles, and less than that in gestational carrier cycles. This finding held true even when other factors were considered showing that the woman's own uterus may be a determining factor.
Gibbons said the study also determined that a diagnosis of male infertility did not affect birth weight or gestational age, yet every female infertility diagnosis was associated with lower birth weight and a reduced gestational age.
Patients diagnosed with a uterine health issue, such as fibroids or other factors, had babies with the lowest birth weights and gestational ages. This led the researchers to examine the uterine environment as it relates to the type of therapy being considered.
Gibbons explains that in standard IVF, an embryo is transferred to a woman who has just undergone controlled ovarian hyperstimulation, while in donor egg IVF and gestational carrier IVF, the embryo is transferred to a "natural" or unstimulated uterus. Then, the researchers looked at IVF utilizing frozen embryo transfer in which an embryo created with a patient's own egg is transferred to her own unstimulated uterus. They found that babies born of frozen embryo transfer cycles had markedly greater birth weights than those born as a result of standard IVF.
"That finding may help women seeking pregnancy and their physicians to consider frozen embryo transfer as a possible option if the uterine health is not a consideration," said Gibbons. "This study shows us how so many factors are related to a successful outcome and we continue to learn where further research may be needed."
The complete study, called "Toward understanding obstetrical outcome in advanced assisted reproduction: varying sperm, oocyte and uterine source and diagnosis," can be found at Fertility and Sterility at www.fertstert.org.
About Texas Children's Hospital
Texas Children's Hospital is committed to a community of healthy children by providing the finest pediatric patient care, education and research. Renowned worldwide for its expertise and breakthrough developments in clinical care and research, Texas Children's is nationally ranked in all ten subspecialties in U.S. News & World Report's list of America's Best Children's Hospitals. Texas Children's also operates the nation's largest primary pediatric care network, with more than 40 offices throughout the greater Houston community. Texas Children's has embarked on a $1.5 billion expansion, Vision 2010, which includes the Jan and Dan Duncan Neurological Research Institute, a comprehensive obstetrics facility focusing on high-risk births and a community hospital in suburban West Houston. For more information on Texas Children's Hospital, go to www.texaschildrens.org. Get the latest news from Texas Children's Hospital by visiting the online newsroom and on Twitter at twitter.com/texaschildrens.
Christy Brunton | EurekAlert!
Scientists Create New Map of Brain’s Immune System
18.02.2019 | Universitätsklinikum Freiburg
Forest Bird Community is endangered in South America
12.02.2019 | Humboldt-Universität zu Berlin
Up to now, OLEDs have been used exclusively as a novel lighting technology for use in luminaires and lamps. However, flexible organic technology can offer much more: as an active lighting surface, it can be combined with a wide variety of materials, not just to modify but to revolutionize the functionality and design of countless existing products. To exemplify this, the Fraunhofer FEP together with the company EMDE development of light GmbH will be presenting hybrid flexible OLEDs integrated into textile designs within the EU-funded project PI-SCALE for the first time at LOPEC (March 19-21, 2019 in Munich, Germany) as examples of some of the many possible applications.
The Fraunhofer FEP, a provider of research and development services in the field of organic electronics, has long been involved in the development of...
For the first time, an international team of scientists based in Regensburg, Germany, has recorded the orbitals of single molecules in different charge states in a novel type of microscopy. The research findings are published under the title “Mapping orbital changes upon electron transfer with tunneling microscopy on insulators” in the prestigious journal “Nature”.
The building blocks of matter surrounding us are atoms and molecules. The properties of that matter, however, are often not set by these building blocks...
Scientists at the University of Konstanz identify fierce competition between the human immune system and bacterial pathogens
Cell biologists from the University of Konstanz shed light on a recent evolutionary process in the human immune system and publish their findings in the...
Laser physicists have taken snapshots of carbon molecules C₆₀ showing how they transform in intense infrared light
When carbon molecules C₆₀ are exposed to an intense infrared light, they change their ball-like structure to a more elongated version. This has now been...
The so-called Abelian sandpile model has been studied by scientists for more than 30 years to better understand a physical phenomenon called self-organized...
11.02.2019 | Event News
30.01.2019 | Event News
16.01.2019 | Event News
20.02.2019 | Life Sciences
20.02.2019 | Medical Engineering
20.02.2019 | Power and Electrical Engineering