Tag: Pregnancy

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Disorders of hypertensive pregnancy associated with subsequent cardiac events

Washington [US], August 13 (ANI): According to new research, women who experienced complications related to developing high blood pressure, or hypertension, during pregnancy had a 63 per cent increased risk for developing cardiovascular disease later in life.

While hypertensive pregnancy complications previously have been linked to increased cardiovascular risks, the current study controlled for pre-pregnancy shared risk factors for these types of complications and cardiovascular disease. Researchers also found that high blood pressure, high cholesterol, type 2 diabetes, or being overweight or obese after pregnancy accounted for most of the increased risk between pregnancy complications and future cardiovascular events.

The findings, published in the Journal of the American College of Cardiology, could support healthcare providers in developing personalized heart disease prevention and monitoring strategies for women who had hypertension during pregnancy. The information could also help bridge the gap that often occurs after a woman ends obstetric care and resumes or starts care with another provider.

Using health data shared by more than 60,000 participants in the Nurses’ Health Study II, the research represents one of the most comprehensive reviews evaluating links between future cardiovascular events in women who have had preeclampsia or gestational hypertension. Gestational hypertension is characterized by an increase in blood pressure during pregnancy. Preeclampsia is a more severe complication marked by a sudden rise in blood pressure that can affect the organs and be dangerous for both mother and baby. Both conditions are often diagnosed after 20 weeks of pregnancy.

“Women with a history of gestational hypertension or preeclampsia should be informed that they have an increased risk for cardiovascular disease,” said Jennifer J. Stuart, Sc.D., a study author and associate epidemiologist in the Division of Women’s Health at Brigham and Women’s Hospital and Harvard Medical School, Boston. “While the American Heart Association and American College of Cardiology recognize these conditions as cardiovascular risk factors, women and their providers have lacked clear direction on what to do in the intervening years between delivery of a hypertensive pregnancy and the onset of cardiovascular disease.”

The researchers’ analysis showed that early screening and monitoring in four targeted areas — blood pressure, cholesterol and glucose levels, and body mass index — could provide even more personalized targets to help delay or possibly prevent future cardiovascular events among these women.

In this study, almost 10% of women developed hypertension during their first pregnancy. Among these women, 3,834 (6.4%) developed preeclampsia and 1,789 (3%) developed gestational hypertension. Women who were obese before pregnancy were three times more likely to experience a hypertensive pregnancy disorder, and those with a family history of heart disease or stroke also shared increased risks. In their analysis, the researchers controlled for these and other important pre-pregnancy factors that could increase the risk of developing hypertension during pregnancy and having a heart attack or stroke later in life.

After about 30 years, when the average age of women in the study was 61 years, approximately 1,074 (1.8%) of study participants had experienced a cardiovascular event, such as a heart attack or stroke. The type of event women had — and when they had it — often overlapped with specific pregnancy complications.

For example, compared to women with normal blood pressure in pregnancy, women with gestational hypertension, which was associated with a 41% increased risk for cardiovascular disease, were more likely to have a stroke about 30 years after their first pregnancy. Women with preeclampsia, which was associated with a 72% increased cardiovascular risk, were more likely to have a coronary artery event, such as a heart attack, as early as 10 years after their first pregnancy.

Post-pregnancy cardiometabolic risk factors, such as obesity, type 2 diabetes, and chronic hypertension, explained most of the increased cardiovascular risk observed among women with gestational hypertension or preeclampsia. Chronic hypertension was the largest contributor of all, accounting for 81% of increased cardiovascular disease risks among women who had gestational hypertension and for 48% of increased risks among women who had preeclampsia. Most women who experienced a hypertensive pregnancy disorder developed chronic hypertension in the years or decades after they gave birth.

“This study reinforces how important it is for women and their healthcare providers to address known cardiovascular disease risk factors, such as obesity or having high blood pressure, while thinking about starting a family and then during and after during pregnancy,” said Victoria Pemberton, R.N.C., a program officer at NHLBI.

For future research, Stuart said diversity is key. Most women in the Nurses’ Health Study II were white, which means the percentage of women affected by different risk factors may vary. The study also provides a foundation to expand on emerging associations, such as studying links between gestational hypertension and stroke and between preeclampsia and coronary artery disease.

Additionally, while over 80% of the increased risk for cardiovascular disease among women with a history of gestational hypertension appears to be jointly accounted for by established cardiovascular risk factors, nearly 40% of the risk for cardiovascular disease following preeclampsia remains unexplained.

Investigating these pathways may help clarify why some women who experienced preeclampsia are more likely to develop heart disease. By better understanding these connections, researchers may be able to contribute insight to help healthcare providers provide even more personalized recommendations and strategies for women at greatest risk.

The research was also supported by grants from the National Cancer Institute and the Eunice Kennedy Shriver National Institute of Child Health and Human Development. (ANI)

This report is auto-generated from ANI news service. ThePrint holds no responsibility for its content.

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Research sheds light on important events that may play a role in infertility

Research sheds light on important events that may play a role in infertility

Everyone considers sperm to be made exclusively by males. But did you know that females also make sperm? Well, it turns out that females also contribute to what makes a sperm a sperm.

Nearly 20 percent of couples in the United States fail to conceive naturally after one year of trying, according to the Centers for Disease Control and Prevention. In species with internal fertilization, such as humans, the ability for a female to become pregnant and carry a pregnancy to term is dependent upon effective interactions between sperm and the female reproductive tract (FRT). When those interactions are defective, the result can be a failed pregnancy. Therefore, understanding the factors that contribute to sperm viability between copulation and fertilization is crucial.

A research team from the Syracuse University College of Arts and Sciences’ Department of Biology and Cornell University, led by Steve Dorus, associate professor of biology at Syracuse University, have been studying the life history of fruit fly (Drosophila melanogaster) sperm to better understand molecular continuity between male and female reproductive tracts. In other words, how the male and female reproductive tracts provide support to keep the sperm viable before fertilization. Their results, published on March 7, 2022 in the journal Proceedings of the National Academy of Sciences USA (PNAS), shed light on important events that may play a role in infertility that up until now have been poorly understood.

The team, which includes members from Syracuse University’s Center for Reproductive Evolution, explored the compositional changes in fruit fly sperm, beginning shortly after they leave the testis, following insemination and finally after protracted storage within the FRT. Fruit flies are powerful model organisms for investigations such as this one because they are easy to culture in the laboratory, have a short generation time and their genetics are richly understood. In their study, the group uncovered that the proteome, or protein makeup, of the sperm undergoes substantial changes after being transferred to the FRT.

For species with internal fertilization, a sperm’s developmental ‘journey’ – on the way to its final destination of fertilizing an egg and beginning a new life – transcends both male and female reproductive tracts. After leaving the testis, sperm travel through the male’s seminal vesicles and descend through the ejaculatory duct, where they mix with seminal fluid proteins. The team found that many of these seminal proteins are progressively lost after sperm migrate beyond the site of insemination within the FRT. Conversely, female-derived proteins that may help the sperm with functions such as energy metabolism, begin to associate with the sperm immediately after mating, signifying a changing of the guard of proteins.

After several days of storage within the FRT, the research team was surprised to discover that nearly 20% of the sperm’s proteins had been replaced by female-derived proteins. The female contributions support sperm viability during the prolonged period between copulation and fertilization. This “hand-off” in the maintenance of sperm viability from males to females means that sperm are materially the product of both sexes, and this may be a crucial aspect of reproduction in all internally-fertilizing species, including humans.

By studying the intimate ways in which sperm interact with the FRT during the final stages of functional maturation, the team’s research advances understanding of animal fertility and the contributions of each sex to reproductive success.

In addition to Dorus and Pitnick, other co-authors from Syracuse University included former postdoctoral researcher Erin McCullough and doctoral graduate Emma Whittington. Co-authors from Cornell University were Professor Mariana Wolfner and postdoctoral researcher Akanksha Singh. The team’s research was funded by the National Science Foundation, the National Institutes of Health and a gift from Mike and Jane Weeden to Syracuse University.

Source:

Journal reference:

McCullough, E.L., et al. (2022) The life history of Drosophila sperm involves molecular continuity between male and female reproductive tracts. PNAS. doi.org/10.1073/pnas.2119899119.

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Health events amongst pregnant females after COVID-19 vaccination

Study: Safety of COVID-19 vaccines in pregnancy: a Canadian National Vaccine Safety (CANVAS) Network study. Image Credit: Huseyin Eren Obuz/Shutterstock

In a recent study posted to the medRxiv* preprint server, researchers evidenced that messenger ribonucleic acid (mRNA)-based coronavirus disease 2019 (COVID-19) vaccines are safe in pregnancy, with lower rates of significant adverse event following immunization (AEFIs) in pregnant women than non-pregnant females.

Study: Safety of COVID-19 vaccines in pregnancy: a Canadian National Vaccine Safety (CANVAS) Network study. Image Credit: Huseyin Eren Obuz/Shutterstock
Study: Safety of COVID-19 vaccines in pregnancy: a Canadian National Vaccine Safety (CANVAS) Network study. Image Credit: Huseyin Eren Obuz/Shutterstock

Background

Multiple research works have published positive recommendations for mRNA-based COVID-19 vaccines in pregnancy, based on the evidence of high efficacy in pre-authorization clinical trials. However, in the absence of a contemporaneous control group to enable comparison with background rates of AEFIs and comparisons based solely on historical rates of AEFIs, apprehensions surrounding the safety of mRNA vaccines during pregnancy are still lurking around.

The Canadian National Vaccine Safety (CANVAS) Network, established during the 2009 influenza pandemic, has been monitoring COVID-19 vaccine safety in Canada since the vaccine rollout in December 2020 to provide rapid, real-time safety data.

The CANVAS actively follow-up individuals with significant health events and actively enrolls control group(s) to enable comparisons with unvaccinated individuals in a similar time frame.

About the study

In the present study, researchers recruited pregnant and non-pregnant females aged 15-49 years, as of 4 November 2021, under the ‘vaccinated’ and ‘control’ cohorts in Canada to evaluate the safety profile of mRNA-based COVID-19 vaccines.

The females in the vaccinated cohort had received the first dose of a vaccine within seven days before enrolling for the study. They had an active email address and telephone number and could communicate in English or French. They reported the occurrence of AEFIs over an email after seven days following each dose of the COVID-19 vaccine and at seven months after their first vaccine dose. The control group participants were unvaccinated and reported significant health events that occurred seven days, 28 days, and six months after enrolling in the study.

All the participants had to report injection site reactions; however, only those who indicated having a significant health event had to provide further details.

The researchers analyzed two types of exposures for the study analysis:

  1. vaccination status among pregnant people;

  2. pregnancy status among vaccinated people.

Two endpoints were analyzed, including ‘significant’ and ‘serious’ health events, including common and uncommon symptoms following the first and second doses of COVID-19 vaccines. The former is defined as a new or worsening of a health event sufficient to cause work/school absenteeism or medical consultation in the previous seven days, and the latter describes any event resulting in hospitalization.

Likewise, they analyzed three vaccine groups:

  1. BNT162b2,

  2. mRNA-1273, and

  3. any mRNA vaccine.

They also examined associations between the outcomes and the exposures, using two sets of univariate/multivariate (MV) logistic regression models. When fitting MV models, they adjusted known or expected covariates such as age group, prior COVID-19 infection, and trimester of pregnancy, as appropriate.

Lastly, they conducted two sensitivity analyses to evaluate the robustness of the findings.

Study findings

Significant health events were lower in pregnant people than in age-matched non-pregnant vaccine recipients. Among pregnant females, AEFI was higher in those who received the second dose of the mRNA-1273 vaccine. However, there was no difference in AEFIs after either dose of the BNT162b2 vaccine.

Initial clinical trials of the mRNA-1273 and BNT162b2 vaccines have reported relatively high rates of AEFIs compared with most routinely used vaccines, including higher rates for dose two than dose one.

The current study analysis revealed similar patterns among pregnant females. Although the analysis specifically quantified the significant and serious AEFI rates in this population for each of the mRNA vaccines, the lower rate of significant AEFIs among pregnant people, compared with vaccinated non-pregnant females, revealed interesting insights.

During pregnancy, dynamic immunologic adaptations occur, for instance, a skewed response towards a T helper cell 2 (Th2)-dominant state. Since mRNA vaccines have specifically elicited a Th1-biased immune response, the Th2-bias during pregnancy may be partially responsible for this lower rate of significant AEFIs.

Conclusions

Considering the high rate of complications related to COVID-19 in pregnancy, it is crucial to maximize vaccine coverage in this at-high risk population for the protection of both the pregnant female and her young infant. Immunized mothers pass on antigen-specific immunoglobulin G (IgG) antibodies against SARS-CoV-2 via placenta or breast milk.

Overall, the study data appropriately informed about the reactogenicity of COVID-19 vaccines during pregnancy. This information should be considered alongside effectiveness and immunogenicity data to make appropriate recommendations about the best use of COVID-19 vaccines in pregnancy. The long-term data from this cohort following a six-month follow-up, when available, could also prove quite useful.  Similar data from countries where the ChAdOx-S vaccines are used could provide a complete overview of the safety of COVID-19 vaccines in pregnancy.

In the future, research studies should identify whether the observed reduced reactogenicity of non-COVID-19 mRNA vaccines in pregnant people in this study is a feature of the vaccine platform or these specific vaccines.

*Important notice

medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.