September 2nd, 2009 
It’s been suggested that gum disease raises the risk of preterm birth in pregnant women and it was thought that getting rid of gum disease may potentially reduce the risk of preterm delivery.
Not so, according to a new study.
“(Our) study,” lead investigator Dr. Steven Offenbacher told Reuters Health, “showed that a standard dental visit to provide periodontal care during pregnancy did not impact pregnancy outcomes, nor did it stop maternal gum problems during pregnancy.”
Offenbacher of the North Carolina Oral Health Institute, Durham and colleagues draw their conclusion from a study involving 1806 pregnant women with periodontal (gum) disease, all of whom were receiving standard obstetric care.
The women were randomized to receive up to four sessions of gum care before the 24th week of pregnancy or after delivery.
According to the investigators, rates of preterm delivery were no different in the two groups. Preterm delivery rates were roughly 13 percent in the women who made the four trips to the dentist and nearly 12 percent in those that did not.
That’s not to say pregnant women should not get their teeth cleaned and treated as needed; they should, the researchers emphasize, noting that treating gum disease during pregnancy is safe.
Worsening of gum disease occurs in about 25 percent of pregnancies. The bacterial infection attacks the teeth-supporting tissues below the gum line. Left untreated, it can lead to tooth loss as well as a host of other problems.
Related
- Infertility treatments may raise preterm birth risk
Couples who conceive through certain types of infertility treatment may have a higher-than-normal likelihood of having a premature baby, a new study suggests.
Danish researchers found that among more than 20,000 women who gave birth at their hospital between 1989 and 2006, those who had conceived through in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) had a higher risk of preterm delivery.
Of the 730 babies born to women who underwent IVF or ICSI, nearly 8 percent were premature and 1.5 percent were very premature — born before the 32nd week of pregnancy. A normal pregnancy lasts 40 weeks.
In comparison, roughly 5 percent of babies born to fertile mothers were premature, and 0.6 percent were born very preterm, the researchers report in the journal Fertility and Sterility.
When the researchers accounted for factors like the mother’s age, weight and exposure to cigarette smoking, the IVF and ICSI procedures were still linked to a 53 percent greater risk of preterm delivery and a doubling in the odds of very premature birth.
Other forms of fertility treatment — namely, fertility drugs and insemination — were not related to the risk of preterm delivery.
Nor was the higher risk with IVF and ICSI explained by elevated rates of twin or higher-order births. The study included only singleton births.
Together, the researchers say, the findings suggest that something about the IVF and ICSI procedures themselves might raise the odds of preterm birth.
Both IVF and ICSI involve joining a woman’s egg and a man’s sperm in a lab dish, then — if fertilization is successful — transferring one or more embryos to the woman’s uterus. ICSI is typically used for male fertility problems, including a low sperm count or poor sperm quality. It involves isolating a single sperm and injecting it directly into the egg.
“The IVF/ICSI procedures include hormone stimulation and mechanical procedures. Both of these factors may influence the risk of preterm delivery,” lead researcher Dr. Kirsten Wisborg, of Aarhus University Hospital in Denmark, told Reuters Health in an email.
The fact that other forms of fertility treatment were not linked to preterm delivery suggests that infertility itself is not to blame, according to Wisborg. However, she pointed out, couples who undergo IVF or ICSI may have a different “reproductive pathology” than those who conceive via fertility drugs or insemination, as they frequently have been infertile for a longer period and have failed to conceive through those “low-tech” fertility treatments.
There may also be other factors, unmeasured in this study, that put women who undergo IVF or ICSI at greater risk of preterm delivery, Wisborg said.
Another possibility, Wisborg said, has to do with the “vanishing twin” phenomenon. Some of the singleton births to women who underwent IVF or ICSI may have begun as a twin pregnancy, with only one fetus surviving beyond the early stages. Research suggests that these surviving fetuses are at increased risk of preterm delivery and low birth weight.
The most important factor in reducing preterm birth risk with IVF or ICSI is to avoid higher-order pregnancies, according to Wisborg. But women can also lower the risk, she said, by not smoking and avoiding alcohol during pregnancy.
- Drugs for depression, anxiety tied to preterm birth
Pregnant women who take certain drugs for depression or anxiety may have heightened risks of preterm delivery or other birth complications, according to a new study.
Researchers found that among nearly 3,000 women who gave birth in Washington State, those who started taking antidepressants known as selective serotonin reuptake inhibitors (SSRIs) in the second or third trimester had a higher risk of preterm birth.
Compared with their counterparts not on the medications, these women were nearly five times more likely to deliver prematurely.
The same risk was not seen, however, among women who started on an SSRI before pregnancy or during the first trimester. SSRIs include drugs like sertraline (Zoloft), paroxetine (Paxil) and fluoxetine (Prozac).
The researchers also found a higher risk of preterm delivery among women who took anti-anxiety drugs known as benzodiazepines, regardless of when they began treatment.
Those drugs, which include medications like lorazepam (Ativan) and alprazolam (Xanax), were linked to higher risks of other complications as well – including low birth weight, newborn respiratory distress and a low Apgar score, a standard measure of newborn health.
The findings of the study are published in the American Journal of Obstetrics & Gynecology.
Exactly what the study means for women on SSRIs or benzodiazepines is not entirely clear. A major limitation is that it could not estimate the benefits of treatment, lead researcher Dr. Ronit Calderon-Margalit, of the Hebrew University-Hadassah School of Public Health in Jerusalem, noted in an email to Reuters Health.
Any risks of using the medications during pregnancy need to be balanced against the risks of leaving depression and anxiety disorders untreated.
“It is very important to have other studies of the risks associated with (these) drugs, but also of benefits associated with treating mothers,” said Calderon-Margalit, who was at the University of Washington in Seattle at the time of the study.
In addition, SSRIs did not appear to present equal risks for all women. Calderon-Margalit described the antidepressant findings as “mostly reassuring” for women who start the drugs before pregnancy or in the first trimester — as most SSRI users in the study had.
The study included 2,793 pregnant women, 11 percent of whom used a psychiatric medication during pregnancy. Of these, 138 were on an SSRI, while 85 used a benzodiazepine.
Among women who were not on any medication, 9 percent gave birth prematurely, versus nearly half of women on benzodiazepines.
Meanwhile, 14 percent of women on SSRIs had a preterm birth, but the elevated risk turned out to be concentrated among those who started an antidepressant after the first trimester. Of those 21 women, 16 delivered prematurely.
Several other birth complications, often related to preterm birth, were also higher-than-average among women on benzodiazepines.
Seventeen percent of their newborns suffered respiratory distress syndrome and one-third ended up in the neonatal intensive care unit. Those figures were 3 percent and 6 percent, respectively, among newborns whose mothers had not used psychiatric medications during pregnancy.
Calderon-Margalit pointed out that most women on benzodiazepines used lorazepam (Ativan), so it is possible that the risks are associated mainly with that drug. However, further research is needed to determine whether any particular medications carry particular risks.
- Natural Delivery OK in Cases of Intrauterine Growth Restriction
Waiting for natural birth is as effective as inducing labor in pregnant women with intrauterine growth restriction (IUGR), a new study shows.
IUGR, which affects about 10 percent of pregnant women, means that the fetus is much smaller than normal. At birth, these babies are more likely to have low blood sugar, an abnormally high red blood cell count and trouble maintaining their body temperature. These babies are also at increased risk for jaundice, infections and cerebral palsy.
Later in life, people who were restricted-growth babies may be more prone to behavioral disorders, obesity, heart disease, type 2 diabetes and high blood pressure.
Currently, doctors have two main approaches for women with suspected IUGR who are nearing delivery. Some doctors induce labor because they’re concerned about complications, while others await natural delivery.
This study compared the effectiveness of the two strategies among 650 women in The Netherlands. The researchers found that median birth weight was significantly lower among babies born after induced labor (2,420 grams) than among those in the spontaneous delivery group (2,560 grams). Both groups of babies had similar rates of adverse post-delivery outcomes.
The findings show that waiting for birth is equally as effective as inducing labor, the researchers concluded.
- Omega-3 Supplements Don’t Reduce Risk of Preterm Birth
Omega-3 fatty acid supplements are believed to have many health benefits, but the one thing they can’t do is help women with a history of delivering their babies early carry their next child to full term, new research finds.
“The omega-3 did not add any benefit,” said study author Dr. Margaret Harper, an associate professor of obstetrics and gynecology at Wake Forest University School of Medicine, Winston-Salem, NC. The study appears in the February issue of Obstetrics & Gynecology.
Harper and her colleagues randomly assigned 852 pregnant women with a history of a preterm birth either to get a daily omega-3 supplement or a placebo beginning about week 16 to 22 and continuing through week 36 of gestation.
All women also received weekly intramuscular hormone injections of hydroxyprogesterone caproate, which has been shown to improve the chances of carrying a baby to term, Harper said.
Her team followed up to see which women delivered before 37 weeks. Full-term is defined as 37 weeks of completed gestation.
Delivery before 37 weeks occurred in 37.8 percent of those taking omega-3, and 41.6 percent of those in the placebo group, a small difference.
Prematurity is the leading cause of newborn death, the authors write in the report, and it is increasing in the United States. A woman who delivers one baby before term is more likely to deliver future babies early.
Harper’s team decided to study the value of the omega-3 supplements after conflicting findings about the value of the supplements for women at high risk of premature delivery. For those at low-risk, she said, the findings seem to agree that omega-3 supplements don’t further reduce the risk of preterm birth.
A recent large review of published studies found only one that showed benefit of the supplements in high-risk women, she said.
According to Harper, omega-3 fatty acids, when metabolized, are converted to much less potent biochemicals called prostaglandins, which make the uterus contract, than are omega-6 fatty acids — also essential fatty acids but typically over-eaten in Western diets. Adding omega-3s to an omega-6-heavy diet, so the thinking went, might result in better chances of carrying the baby to term.
Omega-3 supplements, in other research, have been found to help heart health, to lower blood pressure and to reduce the risk of abnormal heartbeats.
But in Harper’s study, she also noted that women getting omega-3 supplements were more likely to give birth to a baby with respiratory distress syndrome (RDS). While 59 babies (13.9 percent) of those in the omega-3 group had RDS, only 35 (8.7 percent) of those in the placebo group did. In other words, the omega-3 mothers’ babies were 1.6 times more likely to get RDS than infants born to mothers taking placebo. It’s the first time such a finding has been reported in clinical trials, the authors wrote.
“While the study’s results showed no difference, there is early evidence that omega-3 fatty acids are beneficial for fetal brain development, so women should still consider taking them, in conjunction with their doctor’s advice, despite what seems to be little benefit for the reduction of spontaneous preterm birth.”
- Osteopathic care may ease late-pregnancy back pain
Doctors in osteopathic medicine (DOs) are medical doctors additionally trained in gentle manipulative techniques to help restore function, range of motion, and lessen pain in bones and adjoining muscles supporting the neck, back, chest, shoulders, and hips.
Osteopathic manipulation may particularly benefit pregnant women seeking medication-free back pain relief, note Dr. John C. Licciardone and colleagues at University of Texas Health Science Center in Fort Worth.
The study, in the American Journal of Obstetrics and Gynecology, included 144 otherwise healthy pregnant women, about 24 years old on average, with moderate levels of back pain and related movement difficulties during late pregnancy.
The women were randomly assigned to one of three groups: usual obstetric care only, usual obstetric care plus weekly 30-minute osteopathic manipulation treatments from the 30th week of pregnancy through delivery, or usual obstetric care plus sham ultrasound skin stimulation sessions.
Over the course of the study, women in the osteopathic group reported improved back pain and related symptoms, Licciardone noted in an email to Reuters Health. The sham ultrasound group reported no pain improvement and those in the standard care group reported increased pain. However, none of these differences were statistically significant.
Late pregnancy back-related movement problems generally worsened until delivery, but did so to a lesser degree in the osteopathic manipulation group.
Overall, these results suggest osteopathic manipulation may compliment conventional obstetric care, Licciardone and colleagues conclude.
