January 28th, 2010 
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.”
Related
- Probiotics during Pregnancy can Reduce Risk of Eczema
Treating pregnant mothers, and then their infants, with select strains of probiotics — bacteria present naturally in the body and sometimes added to food or dietary supplements to boost immune function — may help prevent a skin condition known as eczema in children with a family history of allergies, particularly during the first 3 months of life, Dutch researchers report.
Eczema is an inflammatory skin condition thought to be related to allergies. Researchers gave more than 150 pregnant women with a family history of allergic diseases either a mixture of three probiotic bacteria or a placebo – inactive pill – during the last six weeks of pregnancy. They also gave the same treatment to the women’s children for 12 months.
Neither the women nor their doctors knew whether they were receiving the probiotics or inactive pills.
They were able to follow up with 102 of the children born to the mothers who took part in the study. During the first 3 months of life, the parents of six in 50 of the subjects who received probiotics reported eczema in their children, compared to 15 or 52 of the placebo group, according to a report of the study in the journal Allergy.
Although the rate of eczema in the two groups became more similar, there was still some benefit after for up to two years.
Put another way, it would be necessary to treat approximately 6 mothers and children to prevent one case of eczema at the age of three months and 12 months, and closer to 7 children at two years.
One of the paper’s 9 authors is employed by Winclove Bio Industries B.V., Amsterdam, which manufactures the probiotic supplements used in the study.
- 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.
- Antidepressants Raise Risk of Pre-Term Birth: Study
Danish women who took antidepressants during pregnancy had twice the risk of pre-term delivery as other women, and their babies were more likely to be admitted to an intensive care unit than those of women who did not take the drugs, researchers reported on Monday.
They said antidepressants, known as selective serotonin reuptake inhibitors or SSRIs, which affect a message-carrying brain chemical called serotonin, may raise the risk of pre-term delivery and affect a baby’s health at birth.
Some prior studies have found that drugs in this class can cross the placenta and appear in the umbilical cord blood of babies whose mothers have taken them.
“The study justifies increased awareness to the possible effects of intrauterine exposure to antidepressants,” Dr. Najaaraq Lund of the Bandim Health Project in Guinea-Bissau, and colleagues wrote in the Archives of Pediatrics and Adolescent Medicine.
About one in 10 pregnant women experience depression during pregnancy. Because depression can jeopardize a pregnant woman’s health, doctors often prescribe antidepressants, but it is not yet clear how these drugs affect a baby’s health.
To study this, Lund and colleagues analyzed data on 57,000 pregnancies and deliveries at Aarhus University Hospital in Skejby, Denmark, between 1989 to 2006.
They identified 329 pregnancies in which the mothers took an SSRI medication, another 4,902 with a history of psychiatric illness not treated with an antidepressant, and 51,700 with no history of psychiatric illness.
Women who took antidepressants while pregnant delivered their babies five days earlier than other women in the study, and had twice the risk of pre-term delivery than women with no history of psychiatric illness.
Babies exposed to antidepressants during pregnancy were far more likely than those in the other two groups to have a five-minute Apgar score — a measure of a newborn’s health — of seven or below. Seven is typically an indicator of a healthy baby.
They were also more likely to be admitted to the neonatal intensive care unit, and some of these babies showed signs of withdrawal, such as jitters, seizures, respiratory problems, infections and jaundice.
The team found no differences in the babies’ head size or birth weight among the three groups.
Antidepressants used by women in the study included Pfizer Inc’s Zoloft, known generically as sertraline; Forest Laboratories Inc’s Celexa, or citalopram, and Lexapro, or escitalopram; Eli Lilly and Co’s Prozac or fluoxetine; and GlaxoSmithKline’s Paxil or paroxetine.
- Migraine drugs don’t up birth defect risk: study
A study in nearly 70,000 pregnant women has found no link between migraine drugs called triptans and the risk of birth defects.
However, the researchers did find a “slight increase” in the risk of excessive bleeding during labor, and the failure of the uterus to contract normally after delivery, for women who used the drugs while pregnant.
Triptans are among the most powerful drugs used for migraine; others include aspirin, Excedrin, and ibuprofen.
While as many as three in 10 women may develop migraines during their childbearing years, women often shy away from using such drugs during pregnancy because of safety concerns, according to study co-author Katerina Nezvalova-Henriksen of the University of Oslo in Norway and her colleagues.
However, the authors of the study in Headache note, untreated migraine may itself carry risks for mother and child; some studies have linked it to pre-eclampsia, a potentially deadly pregnancy complication.
“While it is important to exert caution when using any medications during pregnancy, this study indicates” that pregnant women can either start or continue taking triptans without “any major risk” of miscarriage, premature delivery, or other bad outcomes, the authors conclude.
Nezvalova-Henriksen and her team studied nearly 70,000 women. Two percent, or 1,535, had used sumatriptan (Imitrex), rizatriptan (Maxalt), zolmitriptan (Zomig), or eletriptan (Relpax) in pregnancy.
Less than one percent — 373 women — had used the drugs before getting pregnant but not during pregnancy.
The overall birth defect rate, which encompasses everything from large birthmarks to serious heart problems, was the same among women who had taken triptans during pregnancy and those who didn’t have migraines: 5 percent. Among those who had used triptans in the past but not during pregnancy, it was slightly higher: 6 percent.
The women who used triptans were also more likely than non-triptan users to take other drugs during pregnancy, including acetaminophen (Tylenol) with codeine and non-steroidal anti-inflammatory drugs such as ibuprofen.
However, the rate of major birth defects – such as serious problems of the limbs or internal organs — was 3 percent for all three groups. That rate – about one in 33 births – is about what would be expected for all birth defects in the general population.
The researchers did find that women who used triptans in their second or third trimester were more likely to develop a condition called atonic uterus, in which the uterus fails to contract back to its normal size after delivery. This is the leading cause of excessive bleeding after delivery. They were also more likely to lose significant amounts of blood during labor and delivery.
And during pregnancy, they were more likely to suffer from vomiting than women who had never used the drug; they were also more likely to develop pre-eclampsia or eclampsia, and more likely to have deficiencies in the B-vitamin folate.
While many women who suffer migraines will experience improvements in their symptoms after their first trimester, Nezvalova-Henriksen and her team note, those whose symptoms don’t improve by then aren’t likely to get better.
- Smoking pregnant increases baby’s asthma risk: study
Smoking during pregancy increases the risk of a baby developing asthma up to sixfold, said a Swedish study published at the European Respiratory Society’s annual congress on Monday.
The study by Professeur Anders Bjerg of the Sunderby central hospital in Norrbotten and his specialists showed that smoking leads to babies being born underweight, a fact that has an impact on the development of asthma.
The Swedish doctors studied asthma in about 3,400 children between 1996 and 2008.
The study found that babies of smoking mothers had an average weight of 211 grammes (7.44 ounces) less than those of mothers who do not smoke.
Nearly a quarter (24.3 percent) of smoking mothers’ babies weighed less than 2.5 kilogrammes at birth against 4.1 percent for those of non-smoking women.
In underweight children of women who smoked throughout their pregnancy the asthma risk was at 23.5 percent, against 7.7 percent in children of non-smoking mothers who were born with an average weight.
