Low birth weight

Maternal exposure to air pollutants led to low birth weight

Posted by

0


The association between maternal exposure to chemicals and low birth weight has been explored in recent literature. After conducting an international study, researchers at the University of California in San Francisco suggest that women exposed to particulate air pollution tend to influence their infants’ low birth weight.

“What’s significant is that these are air pollution levels to which practically everyone in the world is commonly exposed,” study researcher Tracey J. Woodruff, PhD, MPH, professor of obstetrics and gynecology and reproductive sciences at UCSF, said in a press release. “These microscopic particles, which are smaller than the width of a human hair, are in the air that we all breathe.”

Woodruff and colleagues utilized data from International Collaboration on Air Pollution and Pregnancy Outcomes (ICAPPO) centers at 14 sites in North America, South America, Europe, Asia and Australia. They examined effect estimates for term low birth weight (LBW) and continuous birth weight related to particulate matter with aerodynamic diameter less than 10 mcm (PM10) and particulate matter with aerodynamic diameter less than 2.5 mcm (PM2.5).

According to researchers, other measurements were conducted on estimates of effect across the centers through meta-analysis. Additionally, meta-regression was completed to evaluate the influence of characteristics and exposure assessment methods based on between-center heterogeneity in other reported estimates.

They found that term LBW was associated with a 10 mcg/m3 increase in PM10 (OR=1.03; 95% CI, 1.01-1.05) and PM2.5 (OR=1.10; 95% CI, 1.03-1.18) exposure throughout the duration of the pregnancy, according to data.

Regarding the fully adjusted random effects meta-analysis, the researchers reported a negative association between the 10 mcg/m3 increase in PM10 with term birth weight as a continuous outcome (–8.9 g; 95% CI, –13.2 to –4.6).

Despite the small associations, the researchers wrote that these findings could be of public health importance due to long-term effects of LBW.

Study supports link between air pollution, adverse birth outcomes

Posted by

0


Maternal exposure to air pollution during pregnancy increased neonates’ odds of low birth weight and being born small for gestational age, according to data in Environmental Research.

The findings expanded upon those reported in a University of California, San Francisco, study published in 2013, which used data on global pollution.

Data derived from Ahmad WA, et al. Environ Res. 2022;doi:10.1016/j.envres.2022.112974.
Data derived from Ahmad WA, et al. Environ Res. 2022;doi:10.1016/j.envres.2022.112974.

Researchers conducted a population-based study of an Israeli cohort to address “concern regarding the impact of particulate matter air pollution of the growth and development of fetuses,” Hagai Levine, MD, MPH, postdoctoral researcher in reproductive epidemiology at Mount Sinai and professor of epidemiology at Hebrew University-Hadassah School of Public Health in Jerusalem, told Healio.

Creating a study cohort

Using data from Maccabi Healthcare Services, Levine and colleagues identified 381,265 singleton neonates born to 223,780 mothers (mean births per mother, 2.3; standard deviation, 1.3) from 2004 to 2015. Babies were born between 24- and 42-weeks’ gestation and weighed between 500 g and 5,000 g.

Researchers assessed maternal exposure to fine particulate matter (PM2.5) by linking satellite data on a spatiotemporal air pollution model with the neonates’ date of birth and maternal residence. They used these data to calculate mean PM2.5 exposure for the duration of the pregnancy.

Of note, siblings were included for analysis if they fit the study criteria, which helped mediate variability attributable to mothers.

Air pollution increases poor birth outcomes

The mean PM2.5 level during pregnancy was 21.8 µg/m3, with the highest values among summer births and lowest in low socioeconomic areas.

Adjusted modeling revealed that a 10 µg/m3 increase in PM2.5 during pregnancy increased the odds of low birth weight (OR = 1.25; 95% CI, 1.09-1.43) and increased the odds of being born small for gestational age (OR = 1.15; 95% CI, 1.06-1.26).

Although maternal air pollution exposure in any trimester affected birth outcomes, the analysis revealed that exposure during the second and third trimesters more strongly correlated with adverse birth outcomes than exposure during the first trimester.

Mothers who were underweight before pregnancy were more susceptible to the impact of air pollution compared with women who were obese before pregnancy. Underweight mothers were also more likely to have babies who had a low birth weight (underweight OR = 1.86 vs. obese OR = 1.15) and who were small for gestational age (underweight OR = 1.6 vs. obese OR = 1.06).

The researchers also found that associations between PM2.5 and birth outcomes were strongest for the firstborn child and for girls.

Given these findings, Levine suggested implementing interventions that may prevent poor birth outcomes related to pollution.

Hagai Levine, MD, MPH

Hagai Levine

“We should instruct mothers how to avoid exposure on high pollution days,” Levine said. “We should improve ventilation. We should reduce exposure at the community, national and international level by better regulation.”

The researchers cautioned that data on pre-pregnancy BMI, alcohol intake and education were missing for some mothers, which may skew their findings. Also, they were unable to track whether a mother changed residence during pregnancy.

Moving forward, Levine highlighted the need for more research on the effect of climate change on birth outcomes.

“We would like to study [the impact of] the combination of exposure to air pollution and to air temperature … on fetal health, of special importance in light of climate change,” he said.

Untreated Depression in Pregnancy Linked to Low Birth Weight

Posted by

0


Untreated depression during pregnancy is associated with an increased risk for preterm birth and low birth weight ― two of the leading causes of mortality and morbidity in infants ― results of a new meta-analysis suggest.

“Although this does not mean that treating depression with antidepressants will reduce these risks, this is an important piece of information for clinicians and women to take into account in the decision-making process around management of depression,” said lead author Alexander Jarde, PhD, postdoctoral fellow, Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada.

Interestingly, the analysis showed that the odds of preterm birth reported in studies by authors receiving support from pharmaceutical companies were significantly higher than the odds reported in studies by authors who did not receive such support.

The study was published online June 8 in JAMA Psychiatry.

Researchers performed an exhaustive literature search for randomized and nonrandomized studies reporting adverse neonatal outcomes in pregnant women with untreated depression in comparison with pregnant women without depression. Studies assessed depression using either a clinical interview/diagnosis or a screening tool or scale.

The authors “rigorously” excluded the confounding effects of antidepressant use, said Dr Jarde.

Primary Outcomes

The primary outcomes were preterm birth before 37 weeks’ gestation or 32 weeks’ gestation, being small for gestational age (birth weight < 10th percentile for sex and gestation), being large for gestational age (birth weight > 90th percentile for sex and gestational age), low birth weight (< 2500 g), and admission to the neonatal intensive care unit.
The analysis included 23 studies. None of the studies reported preterm birth before 32 weeks’ gestation or being large for gestational age. Only one study reported being small for gestational age, and two reported admission to the neonatal intensive care.

The researchers found that in comparison with pregnant women who were without depression, those with untreated depression had a significantly increased risk for both birth before 37 weeks (odds ratio [OR], 1.56; 95% confidence interval [CI], 1.25 – 1.94; 14 studies) and low birth weight (OR, 1.96; 95% CI, 1.24 – 3.10; 8 studies).

A subgroup analysis did not find any significant differences for preterm births between studies assessing depression using a clinical diagnosis or interview (40% of studies) and those using self-reporting questionnaires. However, there was a trend to an increased risk among women with more severe depression.

For low birth weight, subgroup analyses showed a significant increased risk in term infants, which would be about the equivalent of being small for gestational age. For this outcome, analyses also suggested that there was a significant difference between the results of studies of high or acceptable quality (5 or more points on the modified Newcastle-Ottawa scale) and the results of studies of low quality (4 or less points on this scale).

Role of Funding

The researchers also looked at the role of the study authors’ conflicts of interest (COI) ― whether they had direct or indirect funding by, or links to, pharmaceutical companies.

 They found that the risk for preterm birth more than doubled in studies reporting COI (OR, 2.50; 95% CI, 1.70 – 3.65; five studies). These risks were more moderate in studies not reporting such conflicts (OR, 1.34; 95%, CI, 1.08 – 1.66; 9 studies.)

“This difference remained after removing low-quality studies from the analyses and does not seem to be explained by severity of depression,” noted Dr Jarde.

Although there was a trend toward a significant difference in low birth weight outcome between studies reporting and those not reporting COI, this disappeared when low-quality studies were removed.

The authors were unable to explain why COI seemed to affect preterm birth but not low birth weight.

A previous systematic review did not find the same increased risks for preterm birth and low birth weight as did the current study. “Unfortunately, although we did explore this contradiction, we have not found a satisfactory explanation for this yet,” said Dr Jarde.

Related Factors

How might untreated depression during pregnancy affect gestation and birth weight? According to Dr Jarde, it might not be the depression itself, but related factors.

“It’s challenging to isolate the effects of depression alone,” he said. “Depression can be accompanied by other risk factors for preterm birth and low birth weight, such as smoking, anxiety, and low socioeconomic status.”

From an obstetrics point of view, the results suggest that women with untreated depression might benefit from surveillance for preterm birth and small infant size, said Dr Jarde.

He stressed that when deciding on how to manage depression during pregnancy, many factors should be taken into consideration. Such factors, he said, should include each woman’s characteristics, for example, the severity of her depression, her treatment history, and her personal preference.

He also emphasized the need for more rigorous studies that carefully measure and report important risk factors to better understand the risks associated with depression during pregnancy.

The use of antidepressants during pregnancy has been increasing during the past few decades, with 3% to 8% of pregnant women being prescribed or having used antidepressants.

Important Counterpoint

For a comment, Medscape Medical News reached Nada Stotland, MD, professor of psychiatry, Rush University, Chicago, who is former president of the American Psychiatric Association.

She commended the authors for conducting such a study, because there is very little information available on the impact of untreated depression during pregnancy.

“All we ever hear about is the impact of medications in pregnancy,” said Dr Stotland.

Depression is “extremely painful,” she noted, and it is difficult for women and their physicians to know what to do when it occurs during a pregnancy. “While this study doesn’t give us the answers, it provides us with some counterpoint to the idea that taking medications is bad and harmful to the pregnancy.”

Some pregnant women feel guilty or selfish if they take a medication. “This is, again, a counterpoint to that,” said Dr Stotland.

It is important for women whose depression is effectively controlled by an antidepressant to not stop taking the medication during pregnancy, she said. “There’s a very strong likelihood that they’ll succumb to a recurrence or exacerbation of their depression, and it’s important for them to know that taking medication might be a good thing.”

Determining the impact of untreated depression during pregnancy is difficult, inasmuch as studies cannot randomly assign women to not receive treatment, said Dr Stotland. “So I give the authors all the more credit for that.”

That untreated depression causes problems during pregnancy makes sense, said Dr Stotland. “Depression causes you to lose your appetite, it causes you to not be able to sleep, it causes you either to be agitated and moving around too much or to be torpid and lying around, and none of these things, as we know, is good for pregnancy.”

As well, “Depression makes you feel helpless and hopeless,” she added, “so why go to the doctor? Why get checkups? Why take care of yourself?”

Dr Stotland noted that psychotherapy is “quite effective” for depression during pregnancy but that it is not as available as it should be.

A Closer Look at Chemotherapy for Breast Cancer During Pregnancy .

Posted by

0


Infants exposed in utero to chemotherapy have more adverse events than those whose mothers delay treatment until after delivery, but such complications are not clinically important, researchers conclude in the Lancet Oncology.

The study included 400 women diagnosed with early breast cancer during pregnancy, about half of whom received chemotherapy. None received chemotherapy in the first trimester.

Chemotherapy was associated with lower birth weight and an increase in obstetric complications (17% of treated women vs. 9% of the untreated) and neonatal events (31 vs. 7 events). However, the researchers say these outcomes were “not clinically significant” and were “most likely related to premature delivery.” Birth defects, Apgar scores, and blood disorders did not differ between the groups.

The authors conclude that if their results “are substantiated by other studies, breast cancer during pregnancy could be treated as it is in non-pregnant women without putting fetal and maternal outcome at substantially increased risk.”

Source:Lancet Oncology