all pregnancy and childbirth stories

Female lower back has evolved to accommodate strain of pregnancy

404132862 — Wed, 12 Dec 2007 11:12:52 -0500

According to a new study by researchers at Harvard and the University of Texas at Austin, women's lower spines evolved to be more flexible and supportive than men's to increase comfort and mobility during pregnancy, and to accommodate the special biology of carrying a baby for nine months while standing on two feet.

Weight gain between first and second pregnancies and sex ratio

404132862 — Thu, 04 Oct 2007 13:08:13 -0400

A new study from the Harvard School of Public Health (HSPH) and Karolinska Institutet in Stockholm, Sweden, found that mothers who experienced an increase in weight from the beginning of the first pregnancy to the beginning of the second pregnancy may be slightly more likely to give birth to a baby boy during their second pregnancy. The study appears online September 24, 2007 in the journal Fertility & Sterility.

Weight gain in pregnancy linked to overweight in kids

Tue, 10 Jul 2007 15:35:18 -0400

Pregnant women who gain excessive or even appropriate weight, according to current guidelines, are four times more likely than women who gain inadequate weight to have a baby who becomes overweight in early childhood. These findings are from a new study at the Department of Ambulatory Care and Prevention of Harvard Medical School (HMS) and Harvard Pilgrim Health Care, and are published in the April issue of the American Journal of Obstetrics and Gynecology.

Obesity begins in the womb

Thu, 12 Jul 2007 15:06:37 -0400

The obesity epidemic in the United States has spread to include children under 6 years old and particularly infants, according to a Harvard study.

The study of 120,680 kids is the largest to date to report on such young children. During the 22-year period covered, medical records reveal that the prevalence of overweight children less than 6 years old jumped 59 percent, from 6.3 to 10 percent.

The results show surprising increases in the number of overweight children up to 6 months old. From 1980 to 2001, the increase in overweight infants ballooned 74 percent.

"The obesity epidemic has spared no age group," says Matthew Gillman, an associate professor at Harvard Medical School. "These results show that efforts to prevent obesity must start even before birth."

X inactivation seen as contact sport

70652986 — Mon, 26 Mar 2007 06:25:59 -0400

At an early stage in a female embryo's development, one of the two X chromosomes in each of its cells becomes inactivated. In two recent papers, the lab of Jeannie Lee makes important breakthroughs in uncovering how the two X chromosomes decide their fate.

A study in the Jan. 20, 2006 Science shows that the chromosomes literally get together before one of them bows out.

The other, in the March 3, 2006 Molecular Cell, sheds light on the inactivating mechanism, how an RNA called Xist gets switched on in order to envelop the future inactive chromosome.

Moms who breastfeed may be protected from type 2 diabetes

70652986 — Mon, 26 Mar 2007 05:42:34 -0400

Researchers have demonstrated that breastfeeding a child for one year may reduce a woman's risk of developing type 2 diabetes by 15 percent. This study appeared in the Nov. 23, 2005 issue of the Journal of the American Medical Association.

"We've known for a long time that breastfeeding is good for babies," said lead author and Brigham and Women's Hospital researcher Alison Stuebe, MD. "In this study, we found that it's good for moms, too."

The production of milk requires a breastfeeding mother to use an average of 500 calories each day - the equivalent of running four to five miles. According to Stuebe, the additional energy required for lactation is associated with short-term changes in insulin, and glucose. Her study was among the first to look at the long-term association between breastfeeding and incidence of type 2 diabetes. "Our study supports the theory that breastfeeding may be associated with important metabolic changes that influence diabetes risk," she said. "However, more research is needed to determine what hormonal and biological factors are involved."

High blood glucose levels in early pregnancy may deprive embryo of oxygen

70652986 — Mon, 26 Mar 2007 06:22:16 -0400

Research appearing in the October 2005 issue of the American Journal of Physiology: Endocrinology and Metabolism suggests that high blood glucose levels early in pregnancy deprive the embryo of oxygen, interfering with its development.

"Until recently, it was not understood how diabetic pregnancy could cause birth defects. My laboratory wanted to explore this research because the more we know about the effects of the mother's diabetes on the embryo, the more tools we have to identify therapies that may prevent birth defects in diabetic pregnancy," said the study's lead investigator, Mary R. Loeken, an investigator in Joslin's Section on Developmental and Stem Cell Biology and assistant professor of Medicine at Harvard Medical School.

Poor prenatal nutrition permanently damages function of insulin-producing cells in the pancreas

70652986 — Mon, 26 Mar 2007 06:20:09 -0400

To understand the increased risk factor, the researchers mated ordinary mice and separated the mothers into a control group that ate as much chow as they wanted throughout their pregnancies and another group that was fully nourished during the first two weeks but undernourished during the third week. At birth, the second group's babies weighed 23 percent less than the control group.

After delivery, all babies nursed and all mothers ate a full diet and maintained a healthy weight; the previously undernourished mice appeared healthy.

As the young mice matured, their glucose levels began to rise. "By 6 months, these levels had spiked abnormally, to 500 mg/dl - the equivalent of serious, full-blown diabetes in humans," Dr. Mary-Elizabeth Patti said.

Their insulin levels provided a clue as to what caused these results in the mice. In the prenatally undernourished mice, the insulin secretion stayed about the same, regardless of the glucose level in the bloodstream. "The problem was not insulin resistance. It had something to do with insulin secretion," Patti said.

Cultures of the beta cells eventually revealed that the undernourished mice responded to glucose abnormally. "They were somehow 'programmed' to secrete a limited amount of insulin later in life, no matter what signal they got from glucose," Patti said.

Based on the study's results, Patti encouraged people to be aware of the importance of prenatal nutrition and of the importance of those born at a low weight to be sure to exercise and control their weight.

Protein in urine may warn of preeclampsia risk in pregnant women

70652986 — Mon, 26 Mar 2007 07:09:58 -0400

Preeclampsia, or toxemia, develops during pregnancy. In severe cases, it can rapidly escalate to eclampsia, a condition in which the mother suffers a series of potentially fatal complications.

Ananth Karumanchi, MD, a nephrologist in the Department of Medicine at BIDMC and assistant professor of medicine, obstetrics and gynecology at Harvard Medical School, explains that while in a healthy pregnancy, the mother's blood vessels widen to nourish the fetus, the blood vessels narrow in preeclamptic women. "Our discovery suggested this was happening because the anti-angiogenic protein sFlt1 was attaching to and absorbing two pro-angiogenic proteins, PIGF and VEGF."

Appetite hormone restores fertility

70652986 — Mon, 26 Mar 2007 05:35:50 -0400

A hormone called leptin has been trumpeted as an appetite suppressor and a possible treatment for obesity. New research shows that "a clear connection also exists between fat, or energy storage, and the ability to reproduce," says Corrine Welt, an assistant professor of medicine who works at Massachusetts General Hospital, a Harvard affiliate. The women whose fertility was boosted by leptin injections had stopped menstruating as a result of losing an abnormal amount of fat, mainly by overexercising. In their 20s and early 30s, they pared themselves down to carrying about 40 percent less fat than is average for women their age. Such loss of menses, or amenorrhea, is also associated with abnormal levels of thyroid hormones and a loss of bone mass, which can lead to brittle, easily fractured bones. The findings thus raise the possibilities of new treatments for exercise-induced bone loss and for eating disorders, as well as for certain cases of infertility.

Pregnant women carrying boys eat more than those carrying girls

70652986 — Mon, 26 Mar 2007 05:31:33 -0400

Researchers looked at the diets of 244 pregnant American women via a food frequency questionnaire during the second trimester. They found that women expecting a boy had an eight percent higher intake of protein, a nine percent higher intake of carbohydrates, an 11 percent higher intake of animal fats, and a 15 percent higher intake of vegetable fats than women who were carrying a female embryo. The gender of the newborn had no effect on maternal weight gain, even though weight gain is linked to birth weight.

Hospital length of stay may not affect a newborn's health

70652986 — Mon, 26 Mar 2007 05:27:52 -0400

Researcher Jeanne M. Madden and colleagues used seven-and-a-half years of data on 20,366 mother-infant pairs with normal vaginal deliveries within a large Massachusetts health maintenance organization to determine the effects of reductions by the HMO in the postpartum length of stay and a subsequent state law establishing a minimum stay. The investigators measured the effects on lengths of hospital stay, follow-up care for newborns, use of outpatient care and hospital-based services during the first 10 days of life, and expenditures for hospital and home-based maternity services. "Several studies have suggested that short stays are associated with an increased risk of death or readmission of the infant, whereas others have found no effect," Madden said. "In the setting we studied, we found neither policy appeared to affect the health outcomes of newborns. But after coverage for longer stays was guaranteed by law, newborns were less likely to be examined as recommended on day 3 or 4." Funding for this study was provided by the Agency for Healthcare Research and Quality, the Harvard Pilgrim Health Care Foundation, and the Maternal and Child Health Bureau.

Formin gene may explain a common cause of female infertility

70652986 — Mon, 26 Mar 2007 05:28:02 -0400

Harvard Medical School researchers Philip Leder and Benjamin Leader have discovered that oocytes from female mice without the formin gene Fmn2 cannot correctly position the metaphase I DNA-spindle. This produces daughter cells with an abnormal number of chromosomes, the leading cause of female infertility, birth defects, and embryo loss. Genes of the formin family, including Fmn2, are expressed in almost all organisms. The discovery may help explain recurrent pregnancy loss, a condition that affects millions of women throughout the world.

Genetic sonograms may reduce need for amniocentesis

70652986 — Mon, 26 Mar 2007 05:24:41 -0400

Radiologist Beryl Benacerraf is a Harvard Medical School clinical professor of obstetrics, gynecology and reproductive biology at Brigham and Women's Hospital. Benacerraf, a handful of like-minded maternal-fetal ultrasound specialists, and a growing number of older pregnant women believe in clarifying the risk of a genetic abnormality in a fetus by adding a detailed ultrasound known as a genetic sonogram. In skilled hands, the method may pick up about 80 percent of Down syndrome fetuses while reducing the risk for most high-risk women. Benacerraf says "there has to be a better way" than the amniocentesis test routinely used for pregnant women 35 and older.

HIV-1 positive mothers taking vitamin A increase risk of transmitting HIV to newborns

70652986 — Mon, 26 Mar 2007 05:23:32 -0400

In many regions of Africa, between 15 and 30 percent of women attending prenatal care clinics are HIV-1 positive. And 20 to 45 percent of children born to HIV-1 positive mothers become infected through breastfeeding or during intrauterine or labor and delivery periods. Mother-to-child transmission of HIV-1 has been attributed in part to poor maternal micronutrient levels. Multivitamin supplementation has been viewed as a low-cost alternative in areas where drugs are not available. However, researchers from the Harvard School of Public Health and the Muhimbili University College of Health Services in Dar es Salaam, Tanzania, found that women taking vitamin A increased the risk of transmission of HIV-1 to their newborn child compared to mothers who did not take vitamin A. The study results appeared in the Sept. 27, 2002, issue of the journal AIDS. "Our findings give little encouragement for the use of vitamin A supplements in HIV-1 positive pregnant women," said Wafaie Fawzi, lead author of the study and associate professor of nutrition and epidemiology. The study was supported in part by the National Institute of Child Health and Human Development and the Fogarty International Center at the National Institutes of Health.