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Preterm Births, USA, 2007

Infant Deaths — United States, 2000–2007

Unborn Twins Interact With Each Other As Early as 14 Weeks

Pulmonary Hypertension and Pregnancy




Preterm Births, USA, 2007
Preterm infants (those born at <37 completed weeks of gestation) are less likely to survive to their first birthday than infants delivered at higher gestational ages, and those who do survive, especially those born at the earlier end of the preterm spectrum, are more likely to suffer long-term disabilities than infants born at term (1,2).

During 1981–2006, the U.S. preterm birth rate increased >30%, from 9.4% to 12.8% of all live births (3). Although lower during 2007 and 2008, the U.S. preterm birth rate remains higher than any year during 1981–2002 (3,4).

Substantial differences in preterm birth rates across racial/ethnic groups have long been noted (5). However, trends in preterm birth rates among the larger racial/ethnic groups often have differed, (3,6). During 1981–2006, rates rose steadily among births to non-Hispanic white mothers, increased modestly among births to Hispanics, and declined slightly for non-Hispanic black births (3). Declines were noted in preterm birth rates in 2007 and 2008 for each of these groups (3,4).

To examine differences in the risk for preterm birth by race/ethnicity, CDC analyzed final 2007 birth certificate data from the National Vital Statistics System (NVSS).

For 2007, a total 4,316,211 births were reported, of which 546,602 (12.7%) were preterm (3).

For the purposes of this study, gestational age was defined as the interval between the date of the last normal menses and the date of birth; the preterm birth rate is the number of preterm births per 100 total births in a given category. Racial/ethnic origin of the mother are self-reported. National gestational age data according to such attributes as educational attainment, income, and disability status are not available or not collected consistently in NVSS and therefore were not analyzed for this report. Comparable gestational age trend data were not available before the 1981 data year.

In 2007, approximately one of every five infants born to non-Hispanic black mothers was born preterm, compared with one of every eight to nine births to non-Hispanic white and Hispanic women.

The 2007 preterm birth rate for non-Hispanic black infants (18.3%) was 59% higher than the rate for non-Hispanic white infants (11.5%) and 49% higher than the rate for Hispanic infants (12.3%) (Table). Among Hispanic groups, 2007 preterm rates ranged from 11.9% of infants born to mothers of Mexican origin to 14.5% of infants born to mothers of Puerto Rican origin…

…Although the gap between non-Hispanic whites and non-Hispanic blacks in preterm birth risk has narrowed somewhat during the past two decades, this change is attributable primarily to increases in preterm births among non-Hispanic white infants and not to substantial reductions in short gestations among non-Hispanic blacks (4). Demonstrated causes for the wide disparities in preterm risk by race/ethnicity include differences in socioeconomic status, prenatal care, maternal risk behaviors, infection, nutrition, stress, and genetics (1)…
[ED. …AND ABORTION] [CDC, MMWR Supplements, January 14, 2011 / 60(01);78-79,]



Infant Deaths — United States, 2000–2007
Infant mortality rates are an important indicator of the health of a nation because they are associated with maternal health, quality of and access to medical care, socioeconomic conditions, and public health practices (1,2). The U.S. infant mortality rate (the number of deaths among infants aged <1 year per 1,000 live births) declined from approximately 100 deaths per 1,000 births in 1900 (3) to 6.89 in 2000 (4). However, the rate did not decline substantially from 2000 to 2005. The infant mortality rate declined slightly but significantly from 6.86 in 2005 to 6.68 in 2006. The 2007 rate (6.75) was not significantly different from the 2006 rate (6.68) (4–6). In addition, considerable differences in infant mortality rates among racial/ethnic groups have persisted and even increased, demonstrating that not all racial/ethnic groups have benefited equally from social and medical advances (5,7)…

During 2007, a total of 29,138 infant deaths occurred in the United States, with a U.S. infant mortality rate of 6.75 deaths per 1,000 live births (6), compared with 6.89 during 2000 (5).

The infant mortality rate in the United States was higher than the rate for the majority of other developed countries, in part because of a substantially higher percentage of preterm births, a critical risk factor for infant mortality (10).

During 2006, the latest year for which reliable race/ethnicity data are available, the overall U.S. infant mortality rate was 6.68 infant deaths per 1,000 live births, with considerable disparities by race and Hispanic origin (Table).

The highest infant mortality rate was for non-Hispanic black women (13.35), with a rate 2.4 times that for non-Hispanic white women (5.58).

Compared with non-Hispanic white women (5.58), infant mortality rates were 48% higher for American Indian/Alaska Native (AI/AN) women (8.28) and 44% higher for Puerto Rican women (8.01). Compared with non-Hispanic white women (5.58), infant mortality rates were 4% lower for Mexican (5.34) women and 18% and 19% lower for Asian/Pacific Islander (A/PI) (4.55) and Central or South American women (4.52), respectively. Cuban mothers also had a low rate (5.08). Percentage changes from 2000 to 2006 in infant mortality rates for each racial/ethnic group were not statistically significant…

…Risk factors associated with infant mortality rates are also risk factors for preterm or low birth-weight delivery and can affect infant mortality either directly or through the mechanism of preterm or low birth-weight delivery.

In 2006, the percentage of infants born preterm (<37 completed weeks' gestation) was substantially higher for non-Hispanic black (18.5%), Puerto Rican (14.4%), and AI/AN (14.2%) mothers than for non-Hispanic white mothers (11.7%) (13). Infant mortality rates are substantially higher for preterm and low birth-weight infants, and even limited changes in the percentages of preterm or low birth-weight births can have a major impact on infant mortality rates (5)… 

…The recent plateau in the U.S. infant mortality rate and the longstanding racial/ethnic disparities continue to generate concern among researchers and policymakers.

For example, the difference in the infant mortality rate for non-Hispanic whites and non-Hispanic blacks was 138.4% in 2000 and 139.2% in 2006 (Table). Prevention of preterm birth is critical to lowering the overall infant mortality rate and reducing racial/ethnic disparities (21)…  [14 Jan 2011, CDC, MMWR Supplements, 60(01);49-51,]



Unborn Twins Interact With Each Other As Early as 14 Weeks: Unborn twin babies socialize as early as week 14 of gestation, a new study has shown.

Italian researcher Dr. Umberto Castiello of the University of Padova and associates used an advanced method of ultrasonography, which enables the movements of the babies to be recorded over time in 3D, to study five pairs of twins from a sample of low-risk pregnant women attending the Institute of Child Health I.R.C.C.S. Burlo Garofolo.

The purpose of the study was to see how twins interacted with each other in their mothers’ wombs and to determine if the interaction was intentional or accidental.

“Newborns come into the world wired to socially interact,” Dr. Castiello states in the preamble to the study report, then poses the question, “Is a propensity to socially oriented action already present before birth?”

Twin pregnancies provided the research team with a unique opportunity to investigate the social pre-wiring hypothesis.

“Unlike ordinary siblings, twins share a most important environment – the uterus. If a predisposition towards social interaction is present before birth, one may expect twin foetuses to engage in some form of interaction,” the researchers say.

“Although various types of inter-twins contact have been demonstrated starting from the 11th week of gestation,” Dr. Castiello said, “no study has so far investigated the critical question whether intra-pair contact is the result of motor planning rather then the accidental outcome of spatial proximity.”

The five pairs of twins were studied during two separate recording sessions carried out at the 14th and 18th week of gestation.

The first 20-minute recording sessions showed the unborn twins touching each other as well as themselves, and the uterine wall.

During the second recording, four weeks later, their interest in their twin was approximately three times higher, with almost 30 per cent of movements directed towards the sibling. Those movements were also more accurate and of longer duration then self-directed ones, the researchers reported.

“We demonstrate that by the 14th week of gestation twin foetuses do not only display movements directed towards the uterine wall and self-directed movements, but also movements specifically aimed at the co-twin, the proportion of which increases between the 14th and 18th gestational week,” the scientists stated.

The proportional increase in contact with the twin was reported to be consistent among the ten babies studied.

The researchers conclude that performance of movements towards the co-twin is not accidental.

“Starting from the 14th week of gestation twin foetuses plan and execute movements specifically aimed at the co-twin,” the authors wrote, stating that “when the context enables it, as in the case of twin foetuses, other-directed actions are not only possible but predominant over self-directed actions.”

The findings provided quantitative empirical evidence that unborn babies are very much aware of their surroundings and of the presence of a twin with them in their mother’s womb, said the researchers.

The full text of the study, titled “Wired to Be Social: The Ontogeny of Human Interaction” is available here — [see Abstract below]

[12 Jan 2011,,
[12 Jan 2011, T. Baklinski, PADOVA, Italy,

Wired to Be Social: The Ontogeny of Human Interaction [see above]

Newborns come into the world wired to socially interact. Is a propensity to socially oriented action already present before birth? Twin pregnancies provide a unique opportunity to investigate the social pre-wiring hypothesis. Although various types of inter-twins contact have been demonstrated starting from the 11th week of gestation, no study has so far investigated the critical question whether intra-pair contact is the result of motor planning rather then the accidental outcome of spatial proximity.
Methodology/Principal Findings

Kinematic profiles of movements in five pairs of twin foetuses were studied by using four-dimensional ultrasonography during two separate recording sessions carried out at the 14th and 18th week of gestation. We demonstrate that by the 14th week of gestation twin foetuses do not only display movements directed towards the uterine wall and self-directed movements, but also movements specifically aimed at the co-twin, the proportion of which increases between the 14th and 18th gestational week.

Kinematic analysis revealed that movement duration was longer and deceleration time was prolonged for other-directed movements compared to movements directed towards the uterine wall. Similar kinematic profiles were observed for movements directed towards the co-twin and self-directed movements aimed at the eye-region, i.e. the most delicate region of the body.


We conclude that performance of movements towards the co-twin is not accidental: already starting from the 14th week of gestation twin foetuses execute movements specifically aimed at the co-twin.

Competing interests: The authors have declared that no competing interests exist.

Citation: Castiello U, Becchio C, Zoia S, Nelini C, Sartori L, et al. (2010) Wired to Be Social: The Ontogeny of Human Interaction. PLoS ONE 5(10): e13199. doi:10.1371/journal.pone.0013199
Received: July 15, 2010; Accepted: September 13, 2010; Published: October 7, 2010




Pulmonary Hypertension and Pregnancy

Pregnancy in PAH Is Potentially Manageable.

Dr. Dianne Zwicke, a Wisconsin cardiologist has devised a treatment regimen for managing pregnancy in patients with pulmonary arterial hypertension.

The treatment involves management of heart function during pregnancy, delivery of the baby at  36  to 37 weeks, and management of the mom’s condition in the ICU during the crucial period after delivery when maternal  mortality rate is highest.    Excess fluids  are dumped from the mother at a rate of three liters per day for 72 hours after delivery.

Dr Zwicke is not telling women with pulmonary hypertension that they should go get pregnant.  Her method, though very successful,  is not suff

iciently well  tested for that, and requires monitoring and cooperation that is not available everywhere.    She has been telling already pregnant patients that they don’t have to abort the baby.

Read a news feature on Zwicke’s  treatment regimen HERE:

Doctor Devises Strategy for Pulmonary Hypertension

It's a decision that an expectant mother should never have to make: Abort your unborn child and save your own life, or deliver the baby and face possible death a few days later.

Those were the awful choices facing Terrilyn Priessnitz a few weeks after she became pregnant with her first child earlier this year.

Priessnitz, 36, developed shortness of breath in March and a short time later was told she had pulmonary hypertension, an often fatal lung disorder.

Along with the diagnosis came a terrible statistic: Women with pulmonary hypertension who give birth face up to a 50% chance of dying shortly after the baby is born. The usual recommendation is to abort the pregnancy.

"It was hard, the thought of ending it," Priessnitz said from her bed at Aurora Sinai Medical Center, a few days before she gave birth earlier this week. "Either I have this baby, or there are no babies."

Medical literature is replete with warnings about the combination of pulmonary hypertension and pregnancy.

The combination is so dangerous that women with the condition are advised to be sterilized.

Not found in the published annals of medicine is an aggressive treatment devised by a Milwaukee doctor that may allow women like Priessnitz to safely deliver their babies.

The protocol developed by cardiologist Dianne Zwicke, who practices at Aurora St. Luke's Medical Center, now has been used on 45 pregnant women with pulmonary hypertension, mostly in Milwaukee, all of whom survived along with their babies.

The treatment, which involves timing the delivery with the condition of the heart, could have worldwide implications for women with the disease. At least 100,000 people are known to have pulmonary hypertension in the United States, and women are more than twice as likely as men to have it.

The key to the protocol is to constantly use ultrasound to monitor the condition of the right ventricle, the chamber of the heart that pumps blood into the lungs. Those echocardiograms are used to determine when to induce birth, although Zwicke does not allow the women to go beyond 36 weeks.

The women also receive IV diuretics to drain excess fluids and are given other drugs. They are admitted to cardiac intensive care immediately after the baby is born and stay there for at least three days.

Doctors familiar with Zwicke's protocol warned that while it is promising, it is too preliminary to recommend it to women who are deciding whether to give birth.

"The risk is unacceptably high even if it (mortality) is only 10%," said Uri Elkayam, a professor of cardiology and obstetrics and gynecology at the University of Southern California School of Medicine. "If you continue the pregnancy and deliver, you can die."

Elkayam did successfully use Zwicke's approach on a couple of patients, but cautioned that Zwicke's research is unpublished and has not been rigorously reviewed. It addition, it represents a series of case reports mostly from one hospital, not the experience of several doctors with large numbers of patients from a variety of institutions.
Promising treatments

Pulmonary hypertension, which has several known causes but often develops for unknown reasons, is a condition in which the blood pressure is abnormally elevated in the pulmonary artery, the major vessel taking blood from the heart to the lungs.

Priessnitz's pulmonary hypertension was caused by an autoimmune disease that formed blood clots in her lungs. While most of the larger clots have been dissolved, Priessnitz will be on blood thinners for the rest of her life.

The condition makes the heart work harder, a workload that becomes even greater because of the demands of pregnancy and giving birth.

Published reports place the maternal death rate at 30% to 56%, usually within 10 days of delivery.

Even for those who don't become pregnant, the disease has no cure and the overall survival rate is poor, traditionally about three years from the onset of symptoms. However, several promising new treatments have become available in recent years, and some people now can live with the disorder for 15 to 20 years. A lung or heart-lung transplant may be the only option for some patients.

Zwicke said that in addition to the women she has treated here, she also has consulted on several cases in other countries, all 45 with the same outcome: survival of the mother and baby.Still, she said, her approach should not be used to assure women that they can safely deliver their babies. At the same time, she said she does not tell women they have to terminate their pregnancy."If you read the literature, it says you should abort," she said. "(But) what good am I to walk in and say, 'You have to abort?'"

Zwicke said she tells women what the established research shows – a 50% mortality rate – and what her own clinical experience has been with the 45 women who survived.

"We don't push them either way," she said. "They are intelligent adults. It comes down to how much risk they are willing to take. I lose sleep and get gray hair over this."
A good start

Zwicke's research represents a promising start that someday may change clinical practice and allow doctors to reasonably assure women that the odds of dying are low, said Tracy Stevens, a cardiologist and professor of medicine at the University of Missouri-Kansas City School of Medicine.

"Sadly, that will take years," she said.

One problem is that while the protocol used by Zwicke makes sense, it is very sophisticated and requires a variety of specialists. Many hospitals would not be able to offer it, she said.

More importantly, the research needs to be duplicated in controlled clinical trials involving large numbers of women treated at different hospitals, she said… [2 Oct 2009, John Fauber, Journal Sentinel,]