Change in paternity and recurrence of hyperemesis gravidarum

Systematic evidence map of evidence addressing the top 10 priority research questions for hyperemesis gravidarum

OBJECTIVE

Knowledge gaps regarding hyperemesis gravidarum (HG) are substantial. We aimed to systematically identify and map recent evidence addressing the top 10 priority questions for HG, as published in 2021 in a James Lind Alliance Priority Setting Partnership.

DESIGN

Systematic evidence map.

METHODS

We searched MEDLINE and EMBASE on 12 January 2021 and CINAHL on 22 February 2021 with search terms hyperemesis gravidarum, pernicious vomiting in pregnancy and their synonyms. Results were limited to 2009 onwards. Two reviewers independently screened titles and abstracts to assess whether the studies addressed a top 10 priority questions for HG. Differences were discussed until consensus was reached. Publications were allocated to one or more top 10 research questions. Study design was noted, as was patient or public involvement. Two reviewers extracted data synchronously and both cross-checked 10%. Extracted data were imported into EPPI-Reviewer software to create an evidence map.

OUTCOME MEASURES

The number and design of studies in the search yield, displayed per the published 10 priority questions.

RESULTS

Searches returned 4338 results for screening; 406 publications were included in the evidence map. 136 publications addressed multiple questions. Numerous studies address the immediate and long-term outcomes or possible markers for HG (question 8 and 9, respectively 164 and 82 studies). Very few studies seek a possible cure for HG (question 1, 8 studies), preventative treatment (question 4, 2 studies) or how to achieve nutritional requirements of pregnancy (question 10, 17 studies). Case reports/series were most numerous with 125 (30.7%) included. Few qualitative studies (9, 2.2%) were identified. 25 (6.1%) systematic reviews addressed eight questions, or aspects of them. 31 (7.6%) studies included patient involvement.

CONCLUSIONS

There are significant gaps and overlap in the current HG literature addressing priority questions. Researchers and funders should direct their efforts at addressing the gaps in the top 10 questions.

Hyperemesis Gravidarum: Strategies to Improve Outcomes

Hyperemesis gravidarum (HG) is a debilitating and potentially life-threatening pregnancy disease marked by weight loss, malnutrition, and dehydration attributed to unrelenting nausea and/or vomiting; HG increases the risk of adverse outcomes for the mother and child(ren). The complexity of HG affects every aspect of a woman's life during and after pregnancy. Without methodical intervention by knowledgeable and proactive clinicians, life-threatening complications may develop. Effectively managing HG requires an understanding of both physical and psychosocial stressors, recognition of potential risks and complications, and proactive assessment and treatment strategies using innovative clinical tools.

The chance of recurrence of hyperemesis gravidarum: A systematic review

Around 1 % of pregnancies develop Hyperemesis Gravidarum (HG), causing high physical and psychological morbidity. Reports on HG recurrence rate in subsequent pregnancies vary widely. An accurate rate of recurrence is needed for informed reproductive decision making. Our objective is to systematically review and aggregate reported rates for HG subsequent to index pregnancies affected by HG. We searched databases from inception as per the protocol registered on PROSPERO. No language restrictions were applied. Inclusion was not restricted based on how HG was defined; reports of severe NVP were included where authors defined the condition as HG. We included descriptive epidemiological, case control and cohort study designs. Eligibility screening was performed in duplo. We extracted data on populations, study methods and outcomes of significance. A panel of patients reviewed the results and provided discussion and feedback. Quality was assessed with the JBI (2017) critical appraisal tool independently by two reviewers. We performed the searches on 1st November 2019. Our search yielded 4454 unique studies, of which five (n = 40,350 HG cases) matched eligibility criteria; One longitudinal and four population-based cohort studies from five countries. Follow-up ranged from 2 to 31 years. Definition of HG and data collection methods in all the studies created heterogeneity. Quality was low; studies lacked valid and reliable exposure, and/or follow-up was insufficient. Meta-analysis was not possible due to clinical and statistical heterogeneity. This systematic review found five heterogeneous studies reporting recurrence rates from 15 to 81%. Defining HG as hospital cases may have introduced detection bias and contribute to clinical heterogeneity. A prospective longitudinal cohort study using an internationally agreed definition of HG and outcomes meaningful to patients is required to establish the true recurrence rate of HG.

Nausea and vomiting of pregnancy and hyperemesis gravidarum

Nausea and vomiting of pregnancy (NVP) is a common condition that affects as many as 70% of pregnant women. Although no consensus definition is available for hyperemesis gravidarum (HG), it is typically viewed as the severe form of NVP and has been reported to occur in 0.3-10.8% of pregnant women. HG can be associated with poor maternal, fetal and child outcomes. The majority of women with NVP can be managed with dietary and lifestyle changes, but more than one-third of patients experience clinically relevant symptoms that may require fluid and vitamin supplementation and/or antiemetic therapy such as, for example, combined doxylamine/pyridoxine, which is not teratogenic and may be effective in treating NVP. Ondansetron is commonly used to treat HG, but studies are urgently needed to determine whether it is safer and more effective than using first-line antiemetics. Thiamine (vitamin B1) should be introduced following protocols to prevent refeeding syndrome and Wernicke encephalopathy. Recent advances in the genetic study of NVP and HG suggest a placental component to the aetiology by implicating common variants in genes encoding placental proteins (namely GDF15 and IGFBP7) and hormone receptors (namely GFRAL and PGR). New studies on aetiology, diagnosis, management and treatment are under way. In the next decade, progress in these areas may improve maternal quality of life and limit the adverse outcomes associated with HG.

Predictive factors of Hyperemesis Gravidarum: A systematic review

PURPOSE

Hyperemesis gravidarum (HG) is the main cause of hospitalization during the first trimester of pregnancy. Although it has been associated with serious complications, little is known about its predictive factors. The aim of this systematic review was to search for and critically appraise the studies that investigate the predictive factors for HG.

METHODS

Search strategy included PubMed, CENTRAL and EMBASE databases (till December 2017). All studies examining risk factors for HG were included. Screening of available studies was carried out by two reviewers, as well as the quality assessment of the included studies, based on the Newcastle-Ottawa Scale for observational studies.

RESULTS

The search located 308 articles, of which 14 observational studies (four low-, eight medium- and two high-quality), involving 1400 women who met the eligibility criteria. In four studies, there was no association between Helicobacter (H.) Pylori infection and HG, in contrast to two studies which demonstrated such an association. Pre-pregnancy body mass index (BMI), adipose tissue, maternal age, leptin, ghrelin, beta-chorionic gonadotropin (β-hCG), total (T₄) and free thyroxine (fT₄) correlated with HG in various studies, and could be considered as predictive markers. Regarding the high-quality evidence, a cohort study associated leptin and nephatin-1 with HG, whereas a cross-sectional study found no association between H. pylori infection and HG.

CONCLUSIONS

More studies of high quality and adequate sample size have to be carried out to identify the predictive factors for HG.

Recurrence patterns of hyperemesis gravidarum

BACKGROUND

Hyperemesis gravidarum, excessive vomiting in pregnancy, affects approximately 0.3-3.0% of all pregnancies, but the risk is considerably higher in pregnancies following a hyperemetic pregnancy. The reported recurrence rate of hyperemesis gravidarum is wide, ranging from 15-81%, depending on study settings. Factors affecting recurrence of hyperemesis gravidarum are as yet insufficiently studied.

OBJECTIVE

We sought to evaluate the recurrence rate of hyperemesis gravidarum in subsequent pregnancies, to elucidate chronological patterns of recurrence of the condition, and to analyze maternal, environmental, and pregnancy-related factors associated with recurring hyperemesis gravidarum.

STUDY DESIGN

Out of all pregnancies ending in delivery in Finland from 2004 through 2011, data of women who had at least 1 pregnancy ending in delivery following a pregnancy diagnosed with hyperemesis gravidarum were retrieved from hospital discharge register and medical birth register (1836 women, 4103 pregnancies; 1836 index pregnancies and 2267 subsequent pregnancies). The first pregnancy with hyperemesis gravidarum diagnosis was chosen as the index pregnancy, and recurrence rate was calculated by comparing the number of hyperemetic pregnancies that followed the index pregnancy to the total number of pregnancies that followed the index pregnancy. Recurrence patterns of hyperemesis gravidarum were illustrated by presenting the chronological order of the women's pregnancies beginning from the index pregnancy to the end of the follow-up period. The associations between recurring hyperemesis and age, parity, prepregnancy body mass index, smoking, marital and socioeconomic status, domicile, month of delivery, assisted reproductive technology, sex, and number of fetuses were analyzed in both the index pregnancies and in pregnancies following the index pregnancy.

RESULTS

There were 544 pregnancies with a hyperemesis diagnosis and 1723 pregnancies without a hyperemesis diagnosis following the index pregnancies. The overall recurrence rate of hyperemesis gravidarum in pregnancies following the index pregnancy was 24%. In case of >1 subsequent pregnancy, 11% of women were diagnosed with hyperemesis in all of their pregnancies. In the index pregnancies, recurrence of hyperemesis gravidarum was more common among women with parity of 2 than parity of 1 (adjusted odds ratio, 1.33, P = .046). Overweight women (adjusted odds ratio, 0.58, P = .036) or women who smoked after the first trimester (adjusted odds ratio, 0.27, P < .001) had lower recurrence of hyperemesis. In the comparison of the subsequent pregnancies, quitting smoking in the first trimester (adjusted odds ratio, 0.32, P = .010) and smoking continued after the first trimester (adjusted odds ratio, 0.38, P = .002) were associated with lower odds of recurring hyperemesis. Female sex of the fetus was associated with higher odds of recurring hyperemesis (adjusted odds ratio, 1.29, P = .012).

CONCLUSION

In the majority of pregnancies following an earlier hyperemetic pregnancy, hyperemesis gravidarum does not recur, but hyperemetic pregnancies occur in the next pregnancies with little predictability. Only few factors associated with recurring hyperemesis could be identified. Although estimating the probability of recurrence of hyperemesis gravidarum in a subsequent pregnancy based on a woman's first hyperemetic pregnancy turned out not to be feasible, it is reassuring to know that hyperemesis does not appear to become more likely with each pregnancy and that after 1 pregnancy with hyperemesis, the following pregnancy may be different.

Hyperemesis gravidarum: current perspectives

Hyperemesis gravidarum is a complex condition with a multifactorial etiology characterized by severe intractable nausea and vomiting. Despite a high prevalence, studies exploring underlying etiology and treatments are limited. We performed a literature review, focusing on articles published over the last 10 years, to examine current perspectives and recent developments in hyperemesis gravidarum.