Pregnancy management of women with pregestational diabetes

Major malformations risk following early pregnancy exposure to metformin: a systematic review and meta-analysis

Metformin is considered as first-line treatment for type 2 diabetes and an effective treatment for polycystic ovary syndrome (PCOS). However, evidence regarding its safety in pregnancy is limited. We conducted a systematic review and meta-analysis of major congenital malformations (MCMs) risk after first-trimester exposure to metformin in women with PCOS and pregestational diabetes mellitus (PGDM). Randomized controlled trials (RCTs) and observational cohort studies with a control group investigating risk of MCM after first-trimester pregnancy exposure to metformin were searched until December 2021. ORs and 95% CIs were calculated separately according to indications and study type using Mantel-Haenszel method; outcome data were combined using random-effects model. Eleven studies (two RCTs; nine observational cohorts) met the inclusion criteria: four included pregnant women with PCOS, four included those with PGDM and three evaluated both indications separately and were considered in both indication groups. In PCOS group, there were two RCTs (57 exposed, 52 control infants) and five observational studies (472 exposed, 1892 control infants); point estimates for MCM rates in RCTs and observational studies were OR 0.93 (95% CI 0.09 to 9.21) (I2=0%; Q test=0.31; p value=0.58) and OR 1.35 (95% CI 0.37 to 4.90) (I2=65%; Q test=9.43; p value=0.05), respectively. In PGDM group, all seven studies were observational (1122 exposed, 1851 control infants); the point estimate for MCM rates was OR 1.05 (95% CI 0.50 to 2.18) (I2=59%; Q test=16.34; p value=0.01). Metformin use in first-trimester pregnancy in women with PCOS or PGDM do not meaningfully increase the MCM risk overall. However, further studies are needed to characterize residual safety concerns.

Association between microbial composition, diversity, and function of the maternal gastrointestinal microbiome with impaired glucose tolerance on the glucose challenge test

Over the last two decades, the incidence of gestational diabetes (GDM) has almost doubled resulting in almost 9% of pregnant women diagnosed with GDM. Occurring more frequently than GDM is impaired glucose tolerance (IGT), also known as pre-diabetes, but it has been understudied during pregnancy resulting in a lack of clinical recommendations of maternal and fetal surveillance. The purpose of this retrospective, cross-sectional study was to examine the association between microbial diversity and function of the maternal microbiome with IGT while adjusting for confounding variables. We hypothesized that reduced maternal microbial diversity and increased gene abundance for insulin resistance function will be associated with IGT as defined by a value greater than 140 mg/dL on the glucose challenge test. In the examination of microbial composition between women with IGT and those with normal glucose tolerance (NGT), we found five taxa which were significantly different. Taxa higher in participants with impaired glucose tolerance were Ruminococcacea (p = 0.01), Schaalia turicensis (p<0.05), Oscillibacter (p = 0.03), Oscillospiraceae (p = 0.02), and Methanobrevibacter smithii (p = 0.04). When we further compare participants who have IGT by their pre-gravid BMI, five taxa are significantly different between the BMI groups, Enterobacteriaceae, Dialister micraerophilus, Campylobacter ureolyticus, Proteobacteria, Streptococcus Unclassified (species). All four metrics including the Shannon (p<0.00), Simpson (p<0.00), Inverse Simpson (p = 0.04), and Chao1 (p = 0.04), showed a significant difference in alpha diversity with increased values in the impaired glucose tolerance group. Our study highlights the important gastrointestinal microbiome changes in women with IGT during pregnancy. Understanding the role of the microbiome in regulating glucose tolerance during pregnancy helps clinicians and researchers to understand the importance of IGT as a marker for adverse maternal and neonatal outcomes.

The impact of anti-hypertensive treatment on foetal growth and haemodynamics in pregnant women with pre-existing diabetes - An explorative study

OBJECTIVES

To explore the impact of anti-hypertensive treatment of pregnancy-induced hypertension on foetal growth and hemodynamics in women with pre-existing diabetes.

METHODS

A prospective cohort study of 247 consecutive pregnant women with pre-existing diabetes (152 type 1 diabetes; 95 type 2 diabetes), where tight anti-hypertensive treatment was initiated and intensified (mainly with methyldopa) when office blood pressure (BP) ≥135/85 mmHg and home BP ≥130/80 mmHg. Foetal growth was assessed by ultrasound at 27, 33 and 36 weeks and foetal hemodynamics were assessed by ultrasound Doppler before and 1-2 weeks after initiation of anti-hypertensive treatment.

RESULTS

In 215 initially normotensive women, anti-hypertensive treatment for pregnancy-induced hypertensive disorders was initiated in 42 (20%), whilst 173 were left untreated. Chronic hypertension was present in 32 (13%). Anti-hypertensive treatment for pregnancy-induced hypertensive disorders was not associated with foetal growth deviation (linear mixed model, p = 0.681). At 27 weeks, mainly before initiation of anti-hypertensive treatment, the prevalence of small foetuses with an estimated foetal weight <10th percentile was 12% in women initiating anti-hypertensive treatment compared with 4% in untreated women (p = 0.054). These numbers were close to the prevalence of birth weight ≤10th percentile (small for gestational age (SGA)) (17% vs. 4%, p = 0.003). Pulsatility index in the umbilical and middle cerebral artery remained stable after the onset of anti-hypertensive treatment in a representative subgroup (n = 12, p = 0.941 and p = 0.799, respectively).

CONCLUSION

There is no clear indication that antihypertensive treatment causes harm in this particular at-high-risk group of pregnant women with diabetes, such that a larger well-designed study to determine the value of tight antihypertensive control would be worthwhile.

Prepregnancy Counseling Among U.S. Women With Diabetes and Hypertension, 2016-2018

INTRODUCTION

Individuals who have diabetes or hypertension established before pregnancy are at increased risk for maternal and infant health complications. Guidelines recommend that providers deliver prepregnancy counseling, but little is known about the receipt of those services among patients with chronic conditions.

METHODS

Data from the 2016-2018 Pregnancy Risk Assessment Monitoring System, a population-based survey among women with recent live births, were used. Self-reported receipt of prepregnancy counseling on folic acid supplementation, pregnancy desire, contraceptive use, and improving health before pregnancy was examined overall and by diabetes and hypertension status. Multivariable logistic regression examined the association between diabetes and hypertension status and the 4 prepregnancy counseling outcomes. Analyses were conducted in 2020.

RESULTS

Overall, 2.1% of women reported having both diabetes and hypertension, 1.3% reported having diabetes alone, and 3.1% reported having hypertension alone. Less than half of the sample reported receiving each prepregnancy counseling outcome. In adjusted models, women with hypertension alone were more likely to report each counseling outcome than women without diabetes or hypertension. Women with diabetes alone were only more likely to report receiving counseling about improving health, and women with both conditions were not more likely to report the receipt of any counseling outcome under study.

CONCLUSIONS

Women with prepregnancy diabetes, hypertension, or both reported low levels of the recommended prepregnancy counseling, suggesting an evidence-practice gap that should be addressed to optimize maternal and infant health outcomes. There is a need for evidence-based and patient-centered models of prepregnancy counseling for those with diabetes and hypertension.

Potentially modifiable risk factors of preterm delivery in women with type 1 and type 2 diabetes

AIMS/HYPOTHESIS

We aimed to identify potentially modifiable risk factors and causes for preterm delivery in women with type 1 or type 2 (pre-existing) diabetes.

METHODS

A secondary analysis of a prospective cohort study of 203 women with pre-existing diabetes (117 type 1 and 86 type 2 diabetes) was performed. Consecutive singleton pregnancies were included at the first antenatal visit between September 2015 and February 2018.

RESULTS

In total, 27% (n = 55) of the 203 women delivered preterm at median 36 + 0 weeks. When stratified by diabetes type, 33% of women with type 1 diabetes delivered preterm compared with 20% in women with type 2 diabetes (p = 0.04). Women delivering preterm were characterised by a higher prevalence of pre-existing kidney involvement (microalbuminuria or diabetic nephropathy) (16% vs 3%, p = 0.002), preeclampsia (26% vs 5%, p < 0.001), higher positive ultrasound estimated fetal weight deviation at 27 gestational weeks (2.7% vs -1.6% from the mean, p = 0.008), higher gestational weight gain (399 g/week vs 329 g/week, p = 0.01) and similar HbA_1c levels in early pregnancy (51 mmol/mol [6.8%] vs 49 [6.6%], p = 0.22) when compared with women delivering at term. Independent risk factors for preterm delivery were pre-existing kidney involvement (OR 12.71 [95% CI 3.0, 53.79]), higher gestational weight gain (per 100 g/week, OR 1.25 [1.02, 1.54]), higher positive ultrasound estimated fetal weight deviation at 27 gestational weeks (% from the mean, OR 1.07 [1.03, 1.12]) and preeclampsia (OR 7.04 [2.34, 21.19]). Two-thirds of preterm deliveries were indicated and one-third were spontaneous. Several contributing factors to indicated preterm delivery were often present in each woman. The main indications were suspected fetal asphyxia (45%), hypertensive disorders (34%), fetal overgrowth (13%) and maternal indications (8%). Suspected fetal asphyxia mainly included falling insulin requirement and abnormal fetal haemodynamics.

CONCLUSIONS/INTERPRETATIONS

Presence of preeclampsia, higher positive ultrasound estimated fetal weight deviation at 27 gestational weeks and higher gestational weight gain were independent potentially modifiable risk factors for preterm delivery in this cohort of women with pre-existing diabetes. Indicated preterm delivery was common with suspected fetal asphyxia or preeclampsia as the most prevalent causes. Prospective studies evaluating whether modifying these predictors will reduce the prevalence of preterm delivery are warranted.

Maternal diabetes and fetal cardiac output

BACKGROUND

The intrauterine environment is a key determinant for long-term health outcomes. Adverse fetal environments, such as maternal diabetes, obesity and placental insufficiency are strongly associated with long-term health risks in children. Little is known about differences in fetal cardiac output hemodynamics of diabetic mothers (DM) vs. non-diabetic mothers (NDM). Our study aims to investigate the left-sided, right-sided, and combined cardiac output (CCO) in fetuses of DM vs. NDM.

METHODS

Retrospective data were collected in fetuses of DM (N = 532) and NDM (103) at mean gestational age 24 weeks. Examination included 2D echo and pulse wave Doppler. Wilcoxon rank sum tests and Chi-square tests were used to test for distribution difference of maternal and fetal continuous and categorical measures respectively between DM and NDM. Intraclass correlation coefficients were calculated to assess intra-observer reliability of fetal cardiac measurements.

RESULTS

DM mothers had higher mean weight (89.7±22.2 kg) than NDM (76.8±19.8 kg), p <  0.0001 and higher mean BMI (33.4±7.5) than NDM (28.3±5.8), p <  0.0001. C-section delivery occurred in 66% of DM vs. 35% of NDM fetuses. Fetuses of DM mothers had significantly larger semilunar valve diameter, higher left ventricular (LV) output, higher combined cardiac output and lower right ventricle /left ventricle ratio compared to NDM.

CONCLUSION

The greater CCO (adjusted for fetal weight), left sided cardiac output in the fetuses of DM, compared to NDM, represent differences in cardiac adaptation to the diabetic environment.

Pregnancy Outcomes in Women with Long-Duration Type 1 Diabetes-25 Years of Experience

AIMS

Our study aimed to examine the pregnancy outcomes (maternal and fetal) concerning different models of antenatal care across a period of over 25 years (1993-2018) in 459 women with type 1 diabetes. Data from patients with a history of the condition lasting at least 15 years were considered eligible for analysis.

METHODS

The study group was divided into three cohorts based on the different models of treatment used in Poznan University Hospital, Poland: 1993-2000 (cohort I, n = 91), 2001-2005 (cohort II, n = 83), 2006-2018 (cohort III, n = 284). To identify predictors for the selected dichotomous outcomes, we calculated the risks for fetal or maternal complications as dependent variables for cohorts II and III against cohort I, using multivariate logistic regression analysis.

RESULTS

The mean gestational age was 36.8 ± 2.4 weeks in the total cohort. The percentages of deliveries before the 33rd and the 37th weeks was high. We observed a decreasing percentage during the following periods, from 41.5% in the first period to 30.4% in the third group. There was a tendency for newborn weight to show a gradual increase across three time periods (2850, 3189, 3321 g, p < 0.0001). In the last period, we noticed significantly more newborns delivered after 36 weeks with a weight above 4000 g and below 2500 g. Caesarean section was performed in 88% of patients from the whole group, but in the subsequent periods this number visibly decreased (from 97.6%, 86.7%, to 71%, p = 0.001). The number of emergency caesarean sections was lowest in the third period (27.5%, 16.7%, 11.2%, p = 0.006). We observed a decreasing number of "small for gestational age" newborns (SGA) in consecutive periods of treatment (from 24.4% to 8.7%, p = 0.002), but also a higher percentage of "large for gestational age" (LGA) newborns (from 6.1% to 21.6%, p = 0.001). Modification of treatment might be associated with the gradual reduction of SGA rates (cohort I 3.6%, cohort III 2.3% p < 0,0005).

CONCLUSIONS

Strict glycemic and blood pressure control from the very beginning of pregnancy, as well as modern fetal surveillance techniques, may contribute to the improvement of perinatal outcomes in women with long-duration type 1 diabetes.

Predictors of emergency cesarean section in women with preexisting diabetes

OBJECTIVE

Preexisting diabetes in pregnancy is associated with a high risk of emergency cesarean section (CS), which is associated with increased risk of maternal and neonatal complications. Thus, the aim of this study was to identify possible predictors of emergency CS in women with preexisting diabetes.

STUDY DESIGN

This is a secondary analysis of a prospective observational study of 204 women with preexisting diabetes (118 with type 1 diabetes and 86 with type 2) with singleton pregnancies recruited at Rigshospitalet, Copenhagen, Denmark from August 2015 to February 2018. Mode of delivery (trial of labor or planned CS) was individually planned in late pregnancy based on clinical variables reflecting maternal and fetal health including glycemic control and ultrasonically estimated fetal weight. Univariate and multivariable analyses were performed to identify possible predictors of in labor emergency CS.

RESULTS

Trial of labor was planned in 79 % (n = 162) of the women of whom 65 % (n = 105) were delivered vaginally and 35 % (n = 57) by an emergency CS, while the remaining 21 % (n = 42) were offered a planned CS. Nulliparity (adjusted odds ratio (aOR) 5.6 95 % CI 1.7-18.8), presence of a hypertensive disorder (aOR 2.8, 95 % CI 1.2-6.7) and previous CS (aOR 6.7, 95 % CI 1.5-28.9) were independently associated with an emergency CS. Maternal height was inversely associated with emergency CS (aOR 0.6 95 %, CI 0.5-0.9 per 5 cm decrease). Neither maternal HbA1c nor ultrasonically estimated fetal size in late pregnancy were associated with emergency CS. Women scheduled for a planned CS were characterized by poorer glycemic control and higher estimated fetal size than those offered a trial of labor.

CONCLUSION

Nulliparity, presence of a hypertensive disorder, previous CS and shorter maternal height were predictors of emergency CS in women with a planned trial of labor, whereas this not was the case for late pregnancy maternal Hba1c or fetal size estimated by ultrasound.

The influence of carbohydrate consumption on glycemic control in pregnant women with type 1 diabetes

AIMS

To study the influence of the quantity and the quality of carbohydrate consumption on glycemic control in early pregnancy among women with type 1 diabetes.

METHODS

A retrospective study of 107 women with type 1 diabetes who completed 1-3days of diet recording before first antenatal visit, as a part of routine care. The total daily carbohydrate consumption from the major sources (e.g. bread, potatoes, rice, pasta, dairy products, fruits, candy) was calculated. A dietician estimated the overall glycemic index score (scale 0-7).

RESULTS

At least two days of diet recording were available in 75% of the 107 women at mean 64 (SD±14) gestational days. The quantity of carbohydrate consumption from major sources was 180 (±51)g/day. HbA1c was positively associated with the quantity of carbohydrate consumption (β=0.41; 95% CI 0.13-0.70, P=0.005), corresponding to an increase of 0.4% in HbA1c per 100g carbohydrates consumed daily, when adjusted for insulin dose/bodyweight and use of insulin pump treatment. The median (IQR) glycemic index score was 2 (0-3). An adjusted association between HbA1c and glycemic index score was not demonstrated. The women using carbohydrate counting daily (45%) had lower HbA1c compared to the remaining women (6.4 (±0.5) vs. 6.8 (±0.9)% (47±6 vs. 51±10mmol/mol), P=0.01).

CONCLUSIONS

HbA1c in early pregnancy was positively associated with the quantity of carbohydrate consumption regardless of insulin treatment. Carbohydrate counting is probably important for glycemic control in pregnant women with type 1 diabetes.

A best practice position statement on pregnancy in chronic kidney disease: the Italian Study Group on Kidney and Pregnancy

Pregnancy is increasingly undertaken in patients with chronic kidney disease (CKD) and, conversely, CKD is increasingly diagnosed in pregnancy: up to 3 % of pregnancies are estimated to be complicated by CKD. The heterogeneity of CKD (accounting for stage, hypertension and proteinuria) and the rarity of several kidney diseases make risk assessment difficult and therapeutic strategies are often based upon scattered experiences and small series. In this setting, the aim of this position statement of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology is to review the literature, and discuss the experience in the clinical management of CKD in pregnancy. CKD is associated with an increased risk for adverse pregnancy-related outcomes since its early stage, also in the absence of hypertension and proteinuria, thus supporting the need for a multidisciplinary follow-up in all CKD patients. CKD stage, hypertension and proteinuria are interrelated, but they are also independent risk factors for adverse pregnancy-related outcomes. Among the different kidney diseases, patients with glomerulonephritis and immunologic diseases are at higher risk of developing or increasing proteinuria and hypertension, a picture often difficult to differentiate from preeclampsia. The risk is higher in active immunologic diseases, and in those cases that are detected or flare up during pregnancy. Referral to tertiary care centres for multidisciplinary follow-up and tailored approaches are warranted. The risk of maternal death is, almost exclusively, reported in systemic lupus erythematosus and vasculitis, which share with diabetic nephropathy an increased risk for perinatal death of the babies. Conversely, patients with kidney malformation, autosomal-dominant polycystic kidney disease, stone disease, and previous upper urinary tract infections are at higher risk for urinary tract infections, in turn associated with prematurity. No risk for malformations other than those related to familiar urinary tract malformations is reported in CKD patients, with the possible exception of diabetic nephropathy. Risks of worsening of the renal function are differently reported, but are higher in advanced CKD. Strict follow-up is needed, also to identify the best balance between maternal and foetal risks. The need for further multicentre studies is underlined.

To what extent do English language RCT meta-analysis justify induction of low-risk pregnancy for postdates?

Induction for postdates in low-risk pregnancy was adopted with the intent to prevent post-term antepartum stillbirth, the most common cause of perinatal death, based on evidence derived in English language RCT meta-analysis. Systematic English language meta-analysis of RCT studies of induction for postdates in low-risk pregnancy report perinatal mortality rates (PMRs) for low-risk pregnancy ranging from 2.6 to 7.6/1000, based on 2-5 stillbirths among 13-16 perinatal deaths, including diabetic pregnancies as well as other high-risk pregnancies irrelevant to the study question. Baseline PMR≥41 weeks in large international databases for high and low risk pregnancies before routine induction 1998-2003 range from 0.9 to 2.4/1000 or about 300% lower than the reported PMR rates for postdate pregnancies in the expectant management arm in English language RCT meta-analysis. Deaths in the first week far exceed stillbirths in the RCT meta-analysis, the opposite of what is expected. These 2 implausible results bring into question the evidence used to justify induction for postdates≥41 weeks.

First-trimester exposure to metformin and risk of birth defects: a systematic review and meta-analysis

BACKGROUND

Metformin is generally considered a non-teratogenic drug; however, only a few studies specifically designed to assess the rate of congenital anomalies after metformin use have been published in the literature. The objects of the present study were to review all of the prospective and retrospective studies reporting on women treated with metformin at least during the first trimester of their pregnancy and to estimate the overall rate of major birth defects.

METHODS

Databases were searched for English language articles until December 2013. Inclusion criteria for the meta-analysis were: a case group of women with PCOS or pre-pregnancy type 2 diabetes and first-trimester exposure to metformin; a disease-matched control group which was not exposed to metformin or other oral anti-diabetic agents; and a list of the major anomalies in both the study and the control groups. A random effects model was used for the meta-analysis of data, using odds ratios. Studies not fulfilling the inclusion criteria for the meta-analysis but reporting relevant data on major malformations in women diagnosed with PCOS were then used to estimate the overall birth defects rate.

RESULTS

Meta-analysis of nine controlled studies with women affected by PCOS detected that the rate of major birth defects in the metformin-exposed group was not statistically increased compared with the disease-matched control group and that there was no significant heterogeneity among the studies. The metformin-exposed sample was composed of 351 pregnancies and the OR of major birth defects was 0.86 (95% confidence interval: 0.18-4.08; Pheterogeneity = 0.71). By evaluating all of the non-overlapping PCOS studies reported in the literature, even those without an appropriate control group, the overall rate of major anomalies was 0.6% in the sample of 517 women who discontinued the therapy upon conception or confirmation of pregnancy and 0.5% in the sample of 634 women who were treated with metformin throughout the first trimester of their pregnancy. Regarding type 2 diabetic women, we did not identify a sufficient number of studies with metformin exposure during the first trimester to proceed with the meta-analysis.

CONCLUSIONS

There is currently no evidence that metformin is associated with an increased risk of major birth defects in women affected by PCOS and treated during the first trimester. However larger ad hoc studies are warranted in order to definitely confirm the safety and efficacy of this drug in pregnancy.

Analysis of maternal and fetal cardiovascular systems during hyperglycemic pregnancy in the nonobese diabetic mouse

Preconception or gestationally induced diabetes increases morbidities and elevates long-term cardiovascular disease risks in women and their children. Spontaneously hyperglycemic (d)-NOD/ShiLtJ female mice, a type 1 diabetes model, develop bradycardia and hypotension after midpregnancy compared with normoglycemic, age- and gestational day (GD)-matched control (c-NOD) females. We hypothesized that onset of the placental circulation at GD 9-10 and rapid fetal growth from GD 14 correlate with aberrant hemodynamic outcomes in d-NOD females. To develop further gestational time-course correlations between maternal cardiac and renal parameters, high-frequency ultrasonography was applied to d- and c-NOD mice (virgin and at GD 8-16). Cardiac output and left ventricular (LV) mass increased in c-NOD but not in d-NOD mice. Ultrasound and postmortem histopathology showed overall greater LV dilation in d-NOD than in c-NOD mice at mid to late gestation. These changes suggest blunted remodeling and altered functional adaptation of d-NOD hearts. Umbilical cord ultrasounds revealed lower fetal heart rates from GD 12 and lower umbilical flow velocities at GD 14 and GD 16 in d-NOD versus c-NOD pregnancies. From GD 14 to GD 16, d-NOD fetal losses exceeded c-NOD fetal losses. Similar aberrant responses in pregnancies of women with diabetes may elevate postpartum maternal and child cardiovascular risk, particularly if mothers lack adequate prenatal care or have poor glycemic control during gestation.

Diabetes in women: a life-course approach

The increasing prevalence of diabetes in combination with an aging population and increasing female longevity means that it is important to understand the effects of diabetes on women's health. Both type 1 and type 2 diabetes influence health outcomes throughout the life-course. This review article provides a summary of sex differences in diabetes epidemiology and covers specific aspects of the life-course in women including: the menarche, pregnancy and the menopause. It also discusses the associations with other conditions: cardiovascular disease, osteoporosis and cancer.

Type 1 diabetes, diabetic nephropathy, and pregnancy: a systematic review and meta-study

BACKGROUND

In the last decade, significant improvements have been achieved in maternal-fetal and diabetic care which make pregnancy possible in an increasing number of type 1 diabetic women with end-organ damage. Optimal counseling is important to make the advancements available to the relevant patients and to ensure the safety of mother and child. A systematic review will help to provide a survey of the available methods and to promote optimal counseling.

OBJECTIVES

To review the literature on diabetic nephropathy and pregnancy in type 1 diabetes.

METHODS

Medline, Embase, and the Cochrane Library were scanned in November 2012 (MESH, Emtree, and free terms on pregnancy and diabetic nephropathy). Studies were selected that report on pregnancy outcomes in type 1 diabetic patients with diabetic nephropathy in 1980-2012 (i.e. since the detection of microalbuminuria). Case reports with less than 5 cases and reports on kidney grafts were excluded. Paper selection and data extraction were performed in duplicate and matched for consistency. As the relevant reports were highly heterogeneous, we decided to perform a narrative review, with discussions oriented towards the period of publication.

RESULTS

Of the 1058 references considered, 34 fulfilled the selection criteria, and one was added from reference lists. The number of cases considered in the reports, which generally involved single-center studies, ranged from 5 to 311. The following issues were significant: (i) the evidence is scattered over many reports of differing format and involving small series (only 2 included over 100 patients), (ii) definitions are non-homogeneous, (iii) risks for pregnancy-related adverse events are increased (preterm delivery, caesarean section, perinatal death, and stillbirth) and do not substantially change over time, except for stillbirth (from over 10% to about 5%), (iv) the increase in risks with nephropathy progression needs confirmation in large homogeneous series, (v) the newly reported increase in malformations in diabetic nephropathy underlines the need for further studies.

CONCLUSIONS

The heterogeneous evidence from studies on diabetic nephropathy in pregnancy emphasizes the need for further perspective studies on this issue.

The impact of chronic hypertension and pregestational diabetes on pregnancy outcomes

OBJECTIVE

The objective of the study was to examine the impact of chronic hypertension and pregestational diabetes on pregnancy outcomes.

STUDY DESIGN

This was a retrospective cohort study of 532,088 women undergoing singleton births in California in 2006. Women were categorized into chronic hypertension, pregestational diabetes, both, or neither. Pregnancy outcomes were compared using the χ(2) test and multivariable logistic regression to control for potential confounders.

RESULTS

We identified differences in perinatal outcomes between the groups. The rate of preterm birth in women with both conditions was 35.5% versus 25.5% in women with chronic hypertension versus 19.4% in women with pregestational diabetes (P < .001). The rate of small for gestational age was 18.2% in women with both versus 18.3% in women with chronic hypertension versus 9.7% in women with pregestational diabetes (P < .001).

CONCLUSION

The impact of having both chronic hypertension and pregestational diabetes in pregnancy varies, depending on the outcome examined. Although some had an additive effect (eg, stillbirth), others did not (eg, preeclampsia).