Diabetes in pregnancy: maternal and infant outcome

A scientometric visualization analysis of the gut microbiota and gestational diabetes mellitus

Background

The prevalence of gestational diabetes mellitus (GDM), a condition that is widespread globally, is increasing. The relationship between the gut microbiota and GDM has been a subject of research for nearly two decades, yet there has been no bibliometric analysis of this correlation. This study aimed to use bibliometrics to explore the relationship between the gut microbiota and GDM, highlighting emerging trends and current research hotspots in this field.

Results

A total of 394 papers were included in the analysis. China emerged as the preeminent nation in terms of the number of publications on the subject, with 128 papers (32.49%), whereas the United States had the most significant impact, with 4,874 citations. The University of Queensland emerged as the most prolific institution, contributing 18 publications. Marloes Dekker Nitert was the most active author with 16 publications, and Omry Koren garnered the most citations, totaling 154. The journal Nutrients published the most studies (28 publications, 7.11%), whereas PLoS One was the most commonly co-cited journal, with a total of 805 citations. With respect to keywords, research focuses can be divided into 4 clusters, namely, "the interrelationship between the gut microbiota and pregnancy, childbirth," "the relationship between adverse metabolic outcomes and GDM," "the gut microbiota composition and metabolic mechanisms" and "microbiota and ecological imbalance." Key areas of focus include the interactions between the gut microbiota and individuals with GDM, as well as the formation and inheritance of the gut microbiota. Increasing attention has been given to the impact of probiotic supplementation on metabolism and pregnancy outcomes in GDM patients. Moreover, ongoing research is exploring the potential of the gut microbiota as a biomarker for GDM. These topics represent both current and future directions in this field.

Conclusion

This study provides a comprehensive knowledge map of the gut microbiota and GDM, highlights key research areas, and outlines potential future directions.

Fetal sex and maternal pregnancy outcomes: a systematic review and meta-analysis

Background

Since the placenta also has a sex, fetal sex–specific differences in the occurrence of placenta-mediated complications could exist.

Objective

To determine the association of fetal sex with multiple maternal pregnancy complications.

Search strategy

Six electronic databases Ovid MEDLINE, EMBASE, Cochrane Central, Web-of-Science, PubMed, and Google Scholar were systematically searched to identify eligible studies. Reference lists of the included studies and contact with experts were also used for identification of studies.

Selection criteria

Observational studies that assessed fetal sex and the presence of maternal pregnancy complications within singleton pregnancies.

Data collection and analyses

Data were extracted by 2 independent reviewers using a predesigned data collection form.

Main results

From 6522 original references, 74 studies were selected, including over 12,5 million women. Male fetal sex was associated with term pre-eclampsia (pooled OR 1.07 [95%CI 1.06 to 1.09]) and gestational diabetes (pooled OR 1.04 [1.02 to 1.07]). All other pregnancy complications (i.e., gestational hypertension, total pre-eclampsia, eclampsia, placental abruption, and post-partum hemorrhage) tended to be associated with male fetal sex, except for preterm pre-eclampsia, which was more associated with female fetal sex. Overall quality of the included studies was good. Between-study heterogeneity was high due to differences in study population and outcome definition.

Conclusion

This meta-analysis suggests that the occurrence of pregnancy complications differ according to fetal sex with a higher cardiovascular and metabolic load for the mother in the presence of a male fetus.

Funding

None.

Is there a connection between gestational diabetes mellitus, human immunodeficiency virus infection, and tuberculosis?

Pregnancy is associated with insulin resistance similar to that found in type 2 diabetes mellitus (DM). The prevalence of gestational diabetes mellitus (GDM) in key tuberculosis (TB) endemic countries, such as India and China, has been increasing rapidly in the last decade and may be higher in human immunodeficiency virus (HIV) infected women. Pregnancy is also an independent risk factor for developing active TB; however, little is known about the interaction of GDM, HIV and TB. We review the epidemiology and immunology of GDM, and significant research gaps in understanding the interactions between GDM, pregnancy, and TB in women living with and those without HIV.

Sex of the baby and risk of gestational diabetes mellitus in the mother: a systematic review and meta-analysis

AIMS/HYPOTHESIS

It has recently emerged that carrying a male fetus may be associated with poorer maternal beta cell function and an increased risk of gestational diabetes mellitus (GDM). Recognising that the overall impact of fetal sex on maternal glucose metabolism is likely to be subtle, we sought to perform a systematic review and meta-analysis of observational studies to obtain a robust estimate of the incremental maternal risk of GDM associated with the sex of the baby.

METHODS

We searched PubMed and EMBASE to identify observational studies published between 1 January 1950 and 4 April 2015 that reported data on fetal sex and the prevalence of GDM. Two independent reviewers extracted the data and pooled estimates of the RR were calculated by a random-effects model. We considered male fetus as the exposure and prevalence of GDM as the outcome of interest.

RESULTS

We identified 320 studies through electronic searches and nine studies through manual searches. Twenty studies met the inclusion criteria, yielding data on 2,402,643 women. Pooled analysis of these studies demonstrated an increased risk of GDM in women carrying a male fetus compared with women carrying a female fetus (RR 1.04; 95% CI 1.02, 1.06). This result was confirmed in a sensitivity analysis including only studies that applied a stringent definition of GDM (RR 1.03; 95% CI 1.01, 1.06) (I(2) = 0%, p = 0.66).

CONCLUSIONS/INTERPRETATION

Pregnant women carrying a boy have a 4% higher relative risk of GDM than those carrying a girl. The fetus thus may have previously unsuspected effects on maternal glucose metabolism in pregnancy.

Prevalence of pre-eclampsia, pregnancy hypertension and gestational diabetes in population-based data: impact of different ascertainment methods on outcomes

This study investigated strategies for ascertaining pre-eclampsia, pregnancy hypertension and gestational diabetes mellitus from birth records and/or hospital discharge data. The results showed that ascertaining these conditions from a data set that linked birth records to the corresponding maternal hospital record for birth was sufficient for health outcomes research. Antenatal hospital records provided few extra cases and may be necessary only for the ascertainment when a very accurate estimate of the prevalence is required.

Fatores de risco para diabetes mellitus gestacional na coorte de nascimentos de Pelotas, Rio Grande do Sul, Brasil, 2004

Consensos de diversos países referem idade, obesidade e história familiar de diabetes mellitus como fatores de risco para diabetes mellitus gestacional. Outros fatores permanecem controversos. O objetivo deste estudo foi investigar fatores associados ao diabetes mellitus gestacional entre mães dos recém-nascidos da coorte de nascimentos de Pelotas, Rio Grande do Sul, Brasil, em 2004. Foram entrevistadas 4.243 puérperas no hospital, havendo 0,5% de recusas. O diagnóstico de diabetes mellitus gestacional foi auto-referido. A prevalência de diabetes mellitus gestacional foi 2,95% (IC95%: 2,53-3,64). Análise bruta realizada por meio de testes qui-quadrado mostrou associação direta com aumento da idade, escolaridade, nível econômico e índice de massa corporal (IMC) e inversa com altura materna. Cor não branca, história familiar de diabetes mellitus, tabagismo no primeiro e segundo trimestres e atividade física antes da gestação e no primeiro trimestre mostraram-se associados. A análise ajustada hierarquizada realizada através de regressão logística mostrou associação com maior idade, cor não branca, maior escolaridade, história familiar de diabetes mellitus e maior IMC. A altura ficou no limiar da significância. Tabagismo no primeiro e segundo trimestres foi protetor.

Cigarette smoking and risk of gestational diabetes: a systematic review of observational studies

BACKGROUND

Gestational diabetes is a prevalent disease associated with adverse outcomes of pregnancy. Smoking as been associated with glucose intolerance during pregnancy in some but not all studies. Therefore, we aimed to systematically review all epidemiological evidence to examine the association between cigarette smoking during pregnancy and risk of developing gestational diabetes mellitus.

METHODS

We conducted a systematic review of articles published up to 2007, using PubMed, Embase, LILACS e CINAHL to identify the articles. Because this review focuses on studies of smoking during pregnancy, we excluded studies evaluating smoking outside pregnancy. Two investigators independently abstracted information on participant's characteristics, assessment of exposure and outcome, and estimates for the association under study. We evaluated the studies for publication bias and performed heterogeneity analyses. We also assessed the effect of each study individually through sensitivity analysis.

RESULTS

We found and critically reviewed 32 studies, of which 12 met the criteria for inclusion in the review. Most of the studies provided only unadjusted measurements. Combining the results of the individual studies, we obtained a crude odds ratio of 1.03 (99% CI 0.85-1.25). Only 4 studies presented adjusted measurements of association, and no association was found when these alone were analyzed (OR 0.95; 99% CI 0.85-1.07). Subgroup analysis could not be done due to small sample size.

CONCLUSION

The number of studies is small, with major heterogeneity in research design and findings. Taken together, current data do not support an association between cigarette smoking during pregnancy and the risk of gestational diabetes.

Gestational Diabetes Mellitus Outcome in 394 Patients

OBJECTIVE

To determine whether women with gestational diabetes mellitus (GDM) and their offspring have pregnancy outcomes and complications of pregnancy that are different from those in the general obstetric population.

METHODS

Through medical record coding, we identified women with GDM and a singleton pregnancy with cephalic presentation who delivered at St. Paul's Hospital between January 1, 1995, and December 31, 2001. In total, 394 births were analyzed and their outcomes compared with those of a control group of 100 non-diabetic women with the same gestational age (38 weeks) at delivery.

RESULTS

Women with gestational diabetes were of lesser parity (P 0.05), appreciably older (P 0.05), and less likely to be Caucasian (P 0.005) than the general obstetric population. Women with GDM also had a higher risk of Caesarean section (P 0.05), gestational hypertension (P 0.05), and large for gestational age (LGA) deliveries (P 0.005). Of women with GDM, those treated with insulin had a higher incidence of LGA deliveries than those on diet therapy alone. The incidence of respiratory distress syndrome and of need for phototherapy was similar in babies whose mothers had GDM and in those whose mothers did not.

CONCLUSION

Although the rate of complications remains low, GDM creates a predisposition to increased maternal and neonatal complications.

Glucose tolerance and risk of gestational diabetes mellitus in nulliparous women who smoke during pregnancy

Gestational diabetes mellitus has been associated with adverse maternal and infant outcomes, including preeclampsia and fetal macrosomia. Although cigarette smoking has been associated with increased insulin resistance, its effect on gestational diabetes mellitus risk is uncertain. The authors evaluated the effects of smoking on glucose tolerance in a cohort of pregnant women who participated in the Calcium for Preeclampsia Prevention trial, a randomized study of nulliparous women conducted in five US medical centers from 1992 to 1995. Results of screening and diagnostic testing for gestational diabetes mellitus were analyzed. For 3,774 of the 4,589 women enrolled, plasma glucose concentration 1 hour after a 50-g oral glucose challenge and complete information on pregnancy outcome were available; for 3,602 of the women, gestational diabetes mellitus status was known. Adjusted mean 1-hour plasma glucose concentration (mg/dl) was elevated in women who smoked at study enrollment (112.6, 95% confidence interval: 110.0, 115.3) compared with women who had never smoked (108.3, 95% confidence interval: 106.7, 109.8; p < 0.01). Women who smoked were at increased risk of gestational diabetes mellitus when criteria proposed by the National Diabetes Data Group were used (adjusted odds ratio = 1.9, 95% confidence interval: 1.0, 3.6). These findings support an association between smoking and gestational diabetes mellitus.

Cigarette smoking and the risk of gestational and pregestational diabetes in two consecutive pregnancies

OBJECTIVE

Cigarette smoking during pregnancy may increase the risk of gestational diabetes mellitus (GDM) or pregestational diabetes mellitus (PDM). Smoking has been associated positively with hyperinsulinemia and insulin resistance in experimental studies, although the association with diabetes remains unclear. To further explore this issue, we examined the association with smoking in the largest prospective cohort study of GDM and PDM to date.

RESEARCH DESIGN AND METHODS

The study population comprised 212190 women in the population-based Swedish Birth Registry who had their first and second deliveries between January 1987 and December 1995. Maternal characteristics were recorded in a standardized manner at the first prenatal visit, followed by a clinical examination and a standardized in-person interview to assess lifestyle habits. Women were categorized as nonsmokers, light smokers (one to nine cigarettes per day), or moderate-to-heavy smokers (at least 10 cigarettes per day).

RESULTS

Women with GDM in their first pregnancy experienced an eight- to ninefold increased risk of GDM or PDM in their second pregnancy. Cigarette smoking was not associated with increased risk of these conditions. Neither women who smoked during their first and second pregnancies nor those who commenced smoking between pregnancies had a higher risk of GDM or PDM than nonsmokers.

CONCLUSIONS

Our findings do not support an association between cigarette smoking and risk of GDM or PDM in young women of childbearing age.

A history of placental dysfunction and risk of placental abruption

In a population-based historic cohort study, we assessed the possible association of fetal growth retardation, preterm birth and pregnancy-induced hypertension in the immediately preceding pregnancy with placental abruption in the current pregnancy, which would suggest a shared aetiological factor. We also assessed whether chronic hypertension, diabetes mellitus and a history of Caesarean section are associated with placental abruption. Preterm birth and small-for-gestational-age (SGA) in the immediately preceding delivery were associated with an increased risk of placental abruption with unadjusted odds ratios (ORs) of 2.1 [95% CI = 1.9, 2.4] and 1.6 [95% CI = 1.5, 1.8] respectively. Women with a history of an SGA preterm birth in the immediately preceding delivery and an appropriate-for-gestational-age infant in the current had an adjusted OR of 3.2 [95% CI = 2.3, 4.5]. The adjusted odds ratio of placental abruption in women who had pregnancy-induced hypertension in the previous pregnancy, but not in the current, was 1.4 [95% CI = 1.2, 1.7]. Women who delivered a preterm or SGA infant in the previous delivery and had chronic hypertension or diabetes mellitus in the current had adjusted ORs of 2.3-5.7 and 2.5-6.0 respectively. Caesarean section in the previous delivery increased the risk of placental abruption by 40%. These results suggest that pregnancy-induced hypertension, intrauterine growth retardation, preterm delivery and placental abruption share an aetiological factor or represent different clinical expressions of recurring placental dysfunction. Chronic hypertension and diabetes mellitus may cause or aggravate such dysfunction thus causing placental abruption. A history of Caesarean section is associated with an increased risk of placental abruption.

Fuel metabolism in deviant fetal growth in offspring of diabetic women

Fetal growth and development from its very first stages of intrauterine life is significantly influenced by the metabolic environment in which the conceptus develops. Maternal disease states such as gestational diabetes and hypertensive pregnancy, representing maternal conditions involved in extremes of impaired fetal growth (macrosomia versus growth restriction), can serve as excellent examples of the various factors that are involved in intrauterine growth.

The risk of diabetes in a subsequent pregnancy associated with prior history of gestational diabetes or macrosomic infant

Prior studies suggest that diagnosis of gestational diabetes is associated with increased risk for development of gestational diabetes in future pregnancies, and with subsequent onset of established diabetes. The magnitudes of these risks have not been measured. Using linked birth certificate data from Washington State it is possible to identify all women with two or more births occurring during 1984-91. All women with gestational diabetes (n=1375) or with established diabetes (n=220), during their pregnancy for the second or greater birth were identified, and a control group consisting of women whose second or greater birth was not complicated by either condition was randomly selected (n=6380). Data from the birth certificate, for the previous birth, were compared in order to estimate the risks of developing gestational or established diabetes in a subsequent pregnancy among women with prior gestational diabetes relative to women without gestational diabetes. The age-adjusted risk of developing gestational diabetes in the pregnancy for the subsequent birth associated with prior gestational diabetes was 23.2 (95% (confidence interval) CI = 17.2-31.2); the risk of having developed established diabetes by the time of the subsequent birth was 55.5 (95% CI = 34.4-89.4). Women who had a macrosomic infant (>4000 gm) in the prior birth were also at increased risk for developing gestational diabetes (odds ratio OR = 3.3, 95% CI = 2.9-3.8) or established diabetes (OR = 5.8, 95% CI = 4.0-8.5). When data were restricted to patients with only one prior birth, to patients with early prenatal care, to delivery at facilities with long-established protocols for diagnosing gestational diabetes, or to more recent years, the risk estimates remained similarly elevated. The 23-fold increased risk of gestational diabetes associated with having gestational diabetes indicated on the birth certificate of a woman's previous baby, although not unexpected, is still remarkable and reinforces the importance of careful monitoring of women with this history. Although changes in how screening is conducted may account for some of the elevation in risk, our results stayed consistently elevated even when restrictions were made within the data to control for this. The fact that there was a 56-fold increased risk of having developed established diabetes by the time of the subsequent birth on record, associated with prior gestational diabetes, and a 6-fold increased risk associated with a macrosomic infant, supports the idea that these may be early steps in the development of established diabetes, and identifies a group that may benefit from close monitoring and possible intervention.

Congenital malformations in newborns of women with established and gestational diabetes in Washington State, 1984-91

We examined the relationship between diabetes in pregnancy and the development of congenital malformations, in a population-based retrospective study using birth certificate data for all liveborn children delivered from 1984 until 1991 in Washington State. Births to mothers with established and gestational diabetes numbered 1511 and 8869 respectively. For comparison we selected 8934 births to mothers without diabetes. The prevalence of congenital malformations in neonates was 7.2%, 2.8% and 2.1% among mothers with established diabetes, gestational diabetes, and without diabetes, respectively. Newborns of mothers with established diabetes were more likely to have a congenital malformation than newborns of non-diabetic mothers (prevalence odds ratio = 4.0; 95% confidence interval 3.1-5.1). In contrast, there was only a slightly higher prevalence of congenital malformations among newborns of mothers with gestational diabetes (prevalence odds ratio = 1.3; 95% CI 1.0-1.6). The association with maternal established diabetes was greater for neonates with multiple malformations (7.8; 95% CI 3.3-18.1) than for single malformations (2.9-95% CI 2.1-3.9). Four to seven fold associations were observed with skeletal, cleft lip/palate, neural tube and heart abnormalities. The association of established diabetes with congenital malformations was nearly twice as strong among female neonates (prevalence odds ratio = 5.4; 95% CI 3.7-8.0) than among male neonates (prevalence odds ratio = 3.1; 95% CI 2.2-4.5). No such variation was observed for associations with gestational diabetes. This study enlarges on previous work relating congenital anomalies to established diabetes and supports the possibility of a weak association with gestational diabetes.

Birth defects in the infants of aboriginal and non-aboriginal mothers with diabetes in Western Australia

OBJECTIVE

Because of the high prevalence of non-insulin-dependent diabetes in Australian Aborigines, and a suggestion that the prevalence of birth defects was high in the infants of Aboriginal mothers with gestational diabetes, this study was undertaken to determine the prevalence of birth defects in infants of Aboriginal and non-Aboriginal mothers with insulin-dependent, non-insulin-dependent, and gestational diabetes mellitus.

DESIGN

A retrospective cohort study of all births to diabetic and non-diabetic mothers in Western Australia, 1980-1984.

MAIN OUTCOME MEASURE

Birth defects diagnosed at any time up to the age of six years.

RESULTS

Compared with infants of non-diabetic, non-Aboriginal mothers, the prevalence ratio for birth defects in infants of non-Aboriginal insulin-dependent mothers was 2.08 (95% confidence interval, 1.2-3.7), and for infants of mothers with non-insulin-dependent diabetes the ratio was 3.64 (95% CI, 1.5-8.6). The corresponding ratios for infants of Aboriginal mothers were 4.85 (95% CI, 0.8-28.2) and 3.64 (95% CI, 1.3-10.4). For birth defects in infants of gestational diabetic mothers, the prevalence ratio was 1.07 (95% CI, 0.6-1.9) for the non-Aboriginal group and 3.65 (95% CI, 2.3-6.0) for the Aboriginal group. Diabetes could have accounted for 0.14% of birth defects in infants of non-Aboriginal mothers and for 4.62% in infants of Aboriginal mothers.

CONCLUSIONS

The excess of birth defects in infants of Aboriginal women with gestational diabetes may be due to non-insulin-dependent diabetes that predates the pregnancy but is only diagnosed during pregnancy. For Aboriginal infants, maternal diabetes may be the single most common known cause of birth defects that is amenable to change.

From diagnosis to home management: nutritional considerations for women with gestational diabetes

Each year 90,000 women in the United States are diagnosed with gestational diabetes. The transition from diagnosis to home management is a time of high stress for these women. Anxiety may lead to difficulty with self-care in general and the diabetic diet in particular. Follow-up education by a diabetes educator can help clients plan meals that comply with the nutritional meal plan without disrupting the family's eating habits. The client should be taught to measure portions, to recognize sugar as an ingredient in foods and medicines, and to deal with special occasions such as holiday meals, travel, and illness. If extended home care is not feasible, the creative diabetes educator will devise other educational opportunities, such as home videos, telephone support networks, special childbirth classes for women with gestational diabetes, and luncheon meetings at which nutritionally correct meals are served.

The social consequences of insulin-treated diabetes mellitus in patients 20-50 years of age. An epidemiological case-control study

In order to investigate the social consequences of diabetes we sent a questionnaire to all diabetic patients aged 20-50 years and 1.125 matched non-diabetic controls living in the county of Västerbotten in Northern Sweden. The response rate was 87% and 72%, respectively. Patients more often lived alone (18 vs 13% p less than 0.05) and had no children (39 vs 31% p less than 0.01). They were more often the only child of their parents (14 vs 8%, p less than 0.01). Thirty-seven percent of the patients and 22% of the controls (p less than 0.001) had been absent from work because of illness more than one month continuously during the last 3 years and had more often than controls prematurely retired from work (8 vs 2% p less than 0.001). Patients more often had hobbies (86 vs 76%, p less than 0.001) and were participating in social activities (52 vs 41%, p less than 0.001), but were less satisfied with their leisure time (71 vs 80%, p less than 0.001). Forty percent of the patients vs 31% of the controls (p less than 0.01) did not visit neighbours. Fifty-one percent of the patients vs 44% of the controls (p less than 0.05) never spent leisure time with their work mates. No significant differences were found in education, socioeconomic class, dwelling or household economy. The study shows that there are social differences between diabetic patients and non-diabetic people even though they are not overwhelming.