Multiple pregnancies in CKD patients: an explosive mix

Chronic kidney disease, female infertility, and medically assisted reproduction: a best practice position statement by the Kidney and Pregnancy Group of the Italian Society of Nephrology

Fertility is known to be impaired more frequently in patients with chronic kidney disease than in the general population. A significant proportion of chronic kidney disease patients may therefore need Medically Assisted Reproduction. The paucity of information about medically assisted reproduction for chronic kidney disease patients complicates counselling for both nephrologists and gynaecologists, specifically for patients with advanced chronic kidney disease and those on dialysis or with a transplanted kidney. It is in this context that the Project Group on Kidney and Pregnancy of the Italian Society of Nephrology has drawn up these best practice guidelines, merging a literature review, nephrology expertise and the experience of obstetricians and gynaecologists involved in medically assisted reproduction. Although all medically assisted reproduction techniques can be used for chronic kidney disease patients, caution is warranted. Inducing a twin pregnancy should be avoided; the risk of bleeding, thrombosis and infection should be considered, especially in some categories of patients. In most cases, controlled ovarian stimulation is needed to obtain an adequate number of oocytes for medically assisted reproduction. Women with chronic kidney disease are at high risk of kidney damage in case of severe ovarian hyperstimulation syndrome, and great caution should be exercised so that it is avoided. The higher risks associated with the hypertensive disorders of pregnancy, and the consequent risk of chronic kidney disease progression, should likewise be considered if egg donation is chosen. Oocyte cryopreservation should be considered for patients with autoimmune diseases who need cytotoxic treatment. In summary, medically assisted reproduction is an option for chronic kidney disease patients, but the study group strongly advises extensive personalised counselling with a multidisciplinary healthcare team and close monitoring during the chosen medically assisted reproduction procedure and throughout the subsequent pregnancy.

Prenatal exposure to fine particulate matter and the risk of spontaneous preterm birth: A population-based cohort study of twins

Background

Studies in singletons have suggested that prenatal exposure to fine particulate matter (PM_2.5) and some of its chemical components is associated with an increased risk of preterm birth (PTB). However, no study has been conducted in twins.

Purpose

To examine the associations of maternal exposure to total PM_2.5 mass and its carbonaceous components with PTB in twin pregnancies.

Methods

A total of 1,515 pairs of twins and their mothers were enrolled from a previous twin birth cohort that had been conducted at the Shanghai First Maternity and Infant Hospital School of Medicine of Tongji University in China. Participants who had iatrogenic PTBs were excluded. Maternal exposure to total PM_2.5 mass and two carbonaceous components, namely, organic carbon (OC) and black carbon (BC), was estimated by a satellite-based model. The associations between PM_2.5 exposure and the risk of spontaneous PTB were evaluated by logistic regression analysis.

Results

This study found that exposure to total PM_2.5 mass and OC during the second trimester of pregnancy was significantly associated with an increased risk of spontaneous PTB. An interquartile range (IQR) increase in total PM_2.5 mass and OC exposure during the second trimester was associated with 48% (OR = 1.48, 95% CI, 1.06, 2.05) and 50% (OR = 1.50, 95% CI, 1.00, 2.25) increases in the odds of PTB, respectively. However, no significant association was found between BC exposure during any exposure window and the risk of PTB.

Conclusion

The findings suggest that exposure to ambient air pollution with fine particles may be a risk factor for spontaneous PTB in twin pregnancies. The middle stage of pregnancy seems to be a critical window for the impacts of PM_2.5 exposure on PTB in twin pregnancies.

The influence of hypertensive disorders during pregnancy on the perinatal outcome of different chorionic twins

OBJECTIVE

To investigate the influence of hypertensive disorders of pregnancy (HDP) on the perinatal outcomes in twin pregnancies.

METHODS

This was a retrospective single-center study in which, 2160 twin pregnancies delivered between January 2016 and December 2019 were analyzed, 1661 of which were dichorionic (DC) and 499 monochorionic (MC). The perinatal outcomes were compared in 404 twin pregnancies with HDP, including 157 gestational hypertension (GH), 107 mild pre-eclampsia (MPE), 140 severe pre-eclampsia (SPE), and 1756 twins without hypertensive disorders of pregnancy (no-HDP). Multiple linear regression was performed to analyze the association between perinatal outcome and HDP. Stratified sampling by twin chorionicity (DC and MC) was also conducted.

RESULTS

There were 330 (19.9%) DC cases complicated with HDP and 74 (14.8%) MC with HDP, and the difference between the two groups was statistically significant (p=.011). After stratification by chorionicity, in the DC twin, there were significantly more deliveries in the GH group, MPE group, and SPE group before 37 weeks than in the no-HDP group (p=.000). Statistically significant differences were found among the four groups in the average small fetus birthweight, the intertwin weight difference, the relative weight discordance, the growth discordance, the incidence of very low birth weight (VLBW), low birth weight (LBW), and the Apgar scores of the small fetus (p<.05). In MC twins, By comparison only on the average gestational age at delivery, the average small fetus birthweight, Apgar scores of large and small fetuses among the four groups, the difference was statistically significant (p<.05). According to multiple linear regression analysis, after controlling for multiple confounding factors, it was found when the degree of HDP in DC twins increased by one grade, the small fetus birthweight decreased by an average of 19.044 g (p=.007), the intertwin weight difference increased by an average of 14.311 g (p=.034), the relative weight discordance increased by an average of 0.6% (p=.013), and the gestational age at delivery decreased by an average of 0.160 weeks (p=.001).

CONCLUSIONS

The perinatal outcomes of different chorionic twins with HDP are different. HDP has a greater impact on the perinatal outcomes of DC twins. The risk of adverse perinatal outcomes in DC twin pregnancy will increase accordingly with each increase in the grade of HDP, but HDP has little or no relevance on the perinatal outcomes of MC twins.

Impact of growth discordance in twins on preeclampsia based on chorionicity

BACKGROUND

Despite extensive investigations over the last decade, preeclampsia remains an unpredictable pregnancy complication causing perinatal morbidity and mortality worldwide, particularly in twin pregnancies.

OBJECTIVE

This study aimed to determine the relationship between growth discordance in twin pregnancies and the risk for preeclampsia based on chorionicity.

STUDY DESIGN

This was a retrospective single-center study that included 2122 women with twin pregnancies who were admitted to a tertiary hospital between January 2013 and June 2016. Growth discordance was defined as twin birthweight difference ≥20%. Logistic regression models were used to analyze the association between growth discordance and risk for gestational hypertension-preeclampsia in all subjects. Stratified sampling by twin chorionicity (dichorionic and monochorionic) was also conducted. Further analysis was performed to estimate the association between the degree of growth discordance and gestational hypertension-preeclampsia risk in monochorionic and dichorionic twin pregnancies.

RESULTS

The prevalence of growth discordance was 17.6%. In all subjects, growth discordance was associated with increased risk for gestational hypertension-preeclampsia. After stratification by twin chorionicity, growth discordance was associated with an increased risk for gestational hypertension preeclampsia (adjusted odds ratio [AOR], 1.84; 95% confidence interval [CI], 1.26-2.67) and preeclampsia (AOR, 1.82; 95% CI, 1.21-2.73), including mild preeclampsia (AOR, 1.86; 95% CI, 1.02-3.37), severe preeclampsia (AOR, 1.78; 95% CI, 1.06-2.97; P<.05), and early-onset preeclampsia (AOR, 2.98; 95% CI, 1.40-6.32), in the dichorionic twin pregnancy group; however, no significant association was found in the monochorionic twin pregnancy group. A 10% increment of growth discordance in the dichorionic twin pregnancy group was associated with an elevated risk for gestational hypertension preeclampsia (AOR, 1.20; 95% CI, 1.02-1.41) and preeclampsia (AOR, 1.24; 95% CI, 1.04-1.48), including severe preeclampsia (AOR, 1.28; 95% CI, 1.04-1.59) and early-onset preeclampsia (AOR, 1.47; 95% CI, 1.08-2.00), but no significant association was found in the monochorionic twin pregnancy group.

CONCLUSION

Growth discordance is associated with an increased risk for preeclampsia in dichorionic but not in monochorionic twin pregnancy. In addition, the prevalence of preeclampsia increases significantly with increasing degree of growth discordance, reflecting a dose-response relationship in dichorionic twin pregnancy.

Management of Autosomal Dominant Polycystic Kidney Disease (ADPKD) During Pregnancy: Risks and Challenges

Autosomal dominant polycystic kidney disease (ADPKD) affects up to 1 in 1000 people. The disease is characterized by the progressive development of cysts throughout the renal parenchyma due to inherited pathogenic variants in genes including PKD1 or PKD2 and eventually leads to gradual loss of renal function, along with manifestations in other organ systems such as hepatic cysts and intracranial aneurysms. ADPKD management has advanced considerably in recent years due to genetic testing availability, pre-implantation genetic diagnosis technology and new therapeutic agents. Renal disease in pregnancy is recognised as an important risk factor for adverse maternal and fetal outcome. Women with ADPKD and health professionals face multiple challenges in optimising outcomes during the pre-pregnancy, pregnancy and post-partum periods.

Successful management of twin pregnancy in a woman with advanced chronic kidney disease: A case report

RATIONALE

Twin pregnancy in women with chronic kidney disease (CKD) is very rare but poses a great risk to both mother and children. In developing countries like China, advanced CKD twin pregnancies are often terminated. Here, we report a successful case and reviewed related cases, hope to facilitate further study.

PATIENT CONCERNS

A 29-year-old woman with a twin pregnancy showed serum creatinine (Scr) 100 μmol/L (CKD2) at conception. During her 12th week, Scr reached 263 μmol/L (CKD4) with urine protein 3+ and hypertension.

DIAGNOSES

Due to her pregnancy, renal biopsy was not considered. Lab tests showed deterioration of renal function and ultrasound detections showed small kidney size.

INTERVENTIONS

The patient was given basic drug therapy to control her blood pressure and supplemental nutrition without hemodialysis.

OUTCOMES

The patient delivered 2 healthy babies weighting 0.9 and 0.7 kg by cesarean section at the 28th week, but has been under maintenance hemodialysis since then.

LESSONS

Despite low birth weight and preterm delivery, successful twin pregnancies in some patients with CKD could be realized under early multidisciplinary intervention, but this poses great risks for mothers and twins, especially for patients with advanced CKD and those on hemodialysis.

Serious kidney disease in pregnancy: an Australian national cohort study protocol

BACKGROUND

Maternal kidney disease (acute kidney injury (AKI), advanced chronic kidney disease (CKD), dependence on dialysis or a kidney transplant) has a substantial impact on pregnancy, with risks of significant perinatal morbidity. These pregnancies require integrated multidisciplinary care to manage a complex and often challenging clinical situation. The ability to deliver optimal care is currently hindered by a lack of understanding around prevalence, management and outcomes in Australia. This study aims to expand an evidence base to improve clinical care of women with serious kidney impairment in pregnancy.

METHODS/DESIGN

The "Kidney Disease in Pregnancy Study" is a national prospective cohort study of women with stage 3b-5 CKD (including dialysis and transplant) and severe AKI in pregnancy, using the Australasian Maternity Outcomes Surveillance System (AMOSS). AMOSS incorporates Australian maternity units with > 50 births/year (n = 260), capturing approximately 96% of Australian births. We will identify women meeting the inclusion criteria who give birth in Australia between 1st August 2017 and 31st July 2018. Case identification will occur via monthly review of all births in Australian AMOSS sites and prospective notification to AMOSS via renal or obstetric clinics. AMOSS data collectors will capture key clinical data via a web-based data collection tool. The data collected will focus on the prevalence, medical and obstetric clinical care, and maternal and fetal outcomes of these high-risk pregnancies.

DISCUSSION

This study will increase awareness of the issue of serious renal impairment in pregnancy through engagement of 260 maternity units and obstetric and renal healthcare providers across the country. The study results will provide an evidence base for pre-pregnancy counselling and development of models of optimal clinical care, clinical guideline and policy development in Australia. Understanding current practices, gaps in care and areas for intervention will improve the care of women with serious renal impairment, women with high-risk pregnancies, their babies and their families.

Management and outcome of multifetal gestation in a 35-year-old woman with childhood-onset membranoproliferative glomerulonephritis type I

A 35-year-old woman with membranoproliferative glomerulonephritis type I had quintuplet gestation after induced ovulation. Her serum creatinine level and estimated glomerular filtration rate were 0.86 mg/dL and 61.5 mL/min/1.73 m2 before pregnancy. Blood pressure was normal and urinary protein to creatinine ratio was 0.2 g/gCr. Prednisolone 10 mg on alternate-day administration was continued during pregnancy. At 10 weeks of gestation transvaginal selective embryo reduction was performed and five embryos were reduced to twins. Hypertension occurred at 20 weeks of gestation. She developed nephrotic syndrome and serum creatinine level increased to 1.29 mg/dL. Elective cesarean section was performed at 28 weeks of gestation and dichorionic diamniotic twins were born. After delivery blood pressure, serum creatinine level, estimated glomerular filtration rate and serum albumin level in their mother returned to baseline. Her twin infants were well at discharge from neonatal-intensive-care-unit. Incidence of multifetal pregnancies due to the improvement of assisted reproduction technologies and ovulation-inducing hormones has been increasing. Management for multifetal pregnancy in women with chronic kidney disease will be needed further.

Fertility and reproductive care in chronic kidney disease

In both women and men, chronic kidney disease (CKD) is associated with decreased fertility. Though a multitude of factors contribute to the reduction in fertility in this population, progressively impaired function of the hypothalamic-pituitary-gonadal axis appears to play a key role in the pathophysiology. There is limited research on strategies to manage infertility in the CKD population, but intensive hemodialysis, kidney transplantation, medication management and assisted reproductive technologies (ART) have all been proposed. Though fertility and reproductive care are reported as important elements of care by CKD patients themselves, few nephrology clinicians routinely address fertility and reproductive care in clinical interactions. Globally, the average age of parenthood is increasing, with concurrent growth and expansion in the use of ART. Coupled with an increasing prevalence of CKD in women and men of reproductive age, the importance of understanding fertility and reproductive technologies in this population is highlighted. This review endeavors to explore the female and male factors that affect fertility in the CKD population, as well as the evidence supporting strategies for reproductive care.

Twin pregnancy in a patient on chronic haemodialysis who already had three pregnancies

Pregnancy in women with end-stage renal disease is rare. Multiple pregnancies carry a high risk of complications even in healthy individuals. We report the case of a 36-year-old woman who had four pregnancies while she was on dialysis, including one twin pregnancy. The last pregnancy occurred while in the 14th year of hemodialysis. At 8 weeks of gestation (WG), ultrasonography diagnosed a dichorionic diamniotic twin pregnancy. The frequency of dialysis was increased from 3 to 6 times a week and each session lasted 4 h. At 22 WG, polyhydramnios was diagnosed. At 25 WG, the patient presented respiratory distress and was transferred to intensive care where continuous hemodialysis, non-invasive ventilation, antibiotic and tocolysis were initiated. Because of tocolysis failure, a cesarean section was performed and she delivered male twins. The two newborns weighed 790 and 870 g, respectively. To our knowledge, this is the first report of four pregnancies in hemodialysis including one twin pregnancy. The incidence of pregnancy and a better outcome in patients on hemodialysis has increased in recent years but a tight coordination between nephrologists and obstetricians is essential.

A best-practice position statement on pregnancy after kidney transplantation: focusing on the unsolved questions. The Kidney and Pregnancy Study Group of the Italian Society of Nephrology

Kidney transplantation (KT) is often considered to be the method best able to restore fertility in a woman with chronic kidney disease (CKD). However, pregnancies in KT are not devoid of risks (in particular prematurity, small for gestational age babies, and the hypertensive disorders of pregnancy). An ideal profile of the potential KT mother includes "normal" or "good" kidney function (usually defined as glomerular filtration rate, GFR ≥ 60 ml/min), scant or no proteinuria (usually defined as below 500 mg/dl), normal or well controlled blood pressure (one drug only and no sign of end-organ damage), no recent acute rejection, good compliance and low-dose immunosuppression, without the use of potentially teratogen drugs (mycophenolic acid and m-Tor inhibitors) and an interval of at least 1-2 years after transplantation. In this setting, there is little if any risk of worsening of the kidney function. Less is known about how to manage "non-ideal" situations, such as a pregnancy a short time after KT, or one in the context of hypertension or a failing kidney. The aim of this position statement by the Kidney and Pregnancy Group of the Italian Society of Nephrology is to review the literature and discuss what is known about the clinical management of CKD after KT, with particular attention to women who start a pregnancy in non-ideal conditions. While the experience in such cases is limited, the risks of worsening the renal function are probably higher in cases with markedly reduced kidney function, and in the presence of proteinuria. Well-controlled hypertension alone seems less relevant for outcomes, even if its effect is probably multiplicative if combined with low GFR and proteinuria. As in other settings of kidney disease, superimposed preeclampsia (PE) is differently defined and this impairs calculating its real incidence. No specific difference between non-teratogen immunosuppressive drugs has been shown, but calcineurin inhibitors have been associated with foetal growth restriction and low birth weight. The clinical choices in cases at high risk for malformations or kidney function impairment (pregnancies under mycophenolic acid or with severe kidney-function impairment) require merging clinical and ethical approaches in which, beside the mother and child dyad, the grafted kidney is a crucial "third element".

Glomerular Disease in Women

Gender differences exist in the prevalence of glomerular diseases. Data based on histological diagnosis underestimate the prevalence of preeclampsia, which is almost certainly the commonest glomerular disease in the world, and uniquely gender-specific. Glomerular disease affects fertility via disease activity, the therapeutic use of cyclophosphamide, and underlying chronic kidney disease. Techniques to preserve fertility during chemotherapy and risk minimization of artificial reproductive techniques are considered. The risks, benefits, and effectiveness of different contraceptive methods for women with glomerular disease are outlined. Glomerular disease increases the risk of adverse outcomes in pregnancy, including preeclampsia; yet, diagnosis of preeclampsia is complicated by the presence of hypertension and proteinuria that precede pregnancy. The role of renal biopsy in pregnancy is examined, in addition to the use of emerging angiogenic biomarkers. The safety of drugs prescribed for glomerular disease in relation to reproductive health is detailed. The impact of both gender and pregnancy on long-term prognosis is discussed.

A best practice position statement on the role of the nephrologist in the prevention and follow-up of preeclampsia: the Italian study group on kidney and pregnancy

Preeclampsia (PE) is a protean syndrome causing a transitory kidney disease, characterised by hypertension and proteinuria, ultimately reversible after delivery. Its prevalence is variously estimated, from 3 to 5% to 10% if all the related disorders, including also pregnancy-induced hypertension (PIH) and HELLP syndrome (haemolysis, increase in liver enzyme, low platelets) are included. Both nephrologists and obstetricians are involved in the management of the disease, according to different protocols, and the clinical management, as well as the role for each specialty, differs worldwide. The increased awareness of the role of chronic kidney disease in pregnancy, complicating up to 3% of pregnancies, and the knowledge that PE is associated with an increased risk for development of CKD later in life have recently increased the interest and redesigned the role of the nephrologists in this context. However, while the heterogeneous definitions of PE, its recent reclassification, an emerging role for biochemical biomarkers, the growing body of epidemiological data and the new potential therapeutic interventions lead to counsel long-term follow-up, the lack of resources for chronic patients and the increasing costs of care limit the potential for preventive actions, and suggest tailoring specific interventional strategies. The aim of the present position statement of the Kidney and Pregnancy Study Group of the Italian Society of Nephrology is to review the literature and to try to identify theoretical and pragmatic bases for an agreed management of PE in the nephrological setting, with particular attention to the prevention of the syndrome (recurrent PE, presence of baseline CKD) and to the organization of the postpartum follow-up.

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.

Severe diabetic nephropathy in type 1 diabetes and pregnancy--a case series

BACKGROUND

Diabetes and nephropathy are important challenges during pregnancy, increasingly encountered because of the advances in maternal-fetal care.

AIM

To evaluate the maternal and fetal outcomes recorded in "severe" diabetic nephropathy in type 1 diabetic patients referred to nephrological healtcare.

METHODS

The study was performed in an outpatient unit dedicated to kidney diseases in pregnancy (with joint nephrological and obstetric follow-up and strict cooperation with the diabetes unit). 383 pregnancies were referred to the outpatient unit in 2000-2012, 14 of which were complicated by type 1 diabetes. The report includes 12 deliveries, including 2 pregnancies in 1 patient; one twin pregnancy; 2 spontaneous abortions were not included. All cases had long-standing type 1 diabetes (median of 21 (15-31) years), relatively high median age (35 (29-40) years) and end-organ damage (all patients presented laser-treated retinopathy and half of them clinical neuropathy). Median glomerular filtration rate (GFR) at referral was 67 ml/min (48-122.6), proteinuria was 1.6 g/day (0.1-6.3 g/day).

RESULTS

Proteinuria steeply increased in 11/12 patients, reaching the nephrotic range in nine (6 above 5 g/day). One patient increased by 2 chronic kidney disease (CKD) stages. Support therapy included blood pressure and diabetes control, bed rest, and moderate protein restriction. All children were preterm (7 early preterm); early spontaneous labor occurred in 4/12 patients. All singletons were appropriate for gestational age and developed normally after birth. The male twin child died 6 days after birth (after surgery for great vessel transposition).

CONCLUSIONS

Diabetic patients with severe diabetic nephropathy are still present a considerable challenge. Therefore, further investigations are required, particularly on proteinuria management and the occurrence of spontaneous labor.