Obstetric Deliveries in US Women With ESKD: 2002-2015

Pregnancies in Women With Kidney Failure on Home Dialysis in the United States

Introduction

Women with kidney failure have impaired fertility and are at a higher risk of maternal and fetal morbidity and mortality. Little is known about pregnancies in women receiving maintenance home dialysis in the United States.

Methods

Using data from the United States Renal Data System (USRDS), a cohort of 26,387 women aged 15 to 49 years with kidney failure receiving maintenance home dialysis from 2005 to 2018 was examined. We calculated pregnancy rates and identified factors, including the modality associated with pregnancy receiving home dialysis.

Results

Overall, 437 pregnancies were identified in 26,837 women on home dialysis. The unadjusted pregnancy rate was 8.6 per 1000 person-years (PTPY). The unadjusted pregnancy rate was higher on home hemodialysis (16.0 vs. 7.5 PTPY) than on peritoneal dialysis. Women receiving home hemodialysis had a higher adjusted likelihood of pregnancy than women receiving peritoneal dialysis (hazard ratio [HR], 2.34; 95% confidence interval [CI], 1.79-3.05). Compared with women aged 20 to 24 years, the likelihood of pregnancy was lower in women aged 30 to 34 years (HR, 0.64; 95% CI, 0.43-0.96), 35 to 39 years (HR, 0.53; 95% CI, 0.35-0.79), 40 to 44 years (HR, 0.32; 95% CI, 0.21-0.49), and 45 to 49 years (HR, 0.21; 95% CI, 0.13-0.33). Whereas Black women had a higher likelihood of pregnancy (HR, 1.40; 95% CI, 1.07-1.83), there was no difference in likelihood of pregnancy in Asian, Hispanic, and Native Americans as compared to Whites. Body mass index, cause of kidney failure, socioeconomic status, rurality, predialysis nephrology care, or dialysis vintage were not significantly associated with pregnancy on home dialysis.

Conclusion

The pregnancy rate in women with kidney failure undergoing home dialysis is higher with home hemodialysis than with peritoneal dialysis. Younger age and Black race or ethnicity are associated with a higher likelihood of pregnancy among women receiving home dialysis. This information can guide clinicians in preconception counselling and making informed treatment decisions for pregnant women on home dialysis.

Pregnancy in Patients Receiving Home Dialysis

Pregnancy is an important goal for many women with CKD or kidney failure, but important barriers exist, particularly as CKD stage progresses. Women with advanced CKD often have a limited fertility window and may miss their opportunity for a pregnancy if advised to defer until after kidney transplantation. Pregnancy rates in women with advanced kidney failure or receiving dialysis remain low, and despite the improved outcomes in recent years, these pregnancies remain high risk for both mother and baby with high rates of preterm birth due to both maternal and fetal complications. However, with increased experience and advances in models of care, this paradigm may be changing. Intensive hemodialysis regimens have been shown to improve both fertility and live birth rates. Increasing dialysis intensity and individualizing dialysis prescription to residual renal function, to achieve highly efficient clearances, has resulted in improved live birth rates, longer gestations, and higher birth weights. Intensive hemodialysis regimens, particularly nocturnal and home-based dialysis, are therefore a potential option for women with kidney failure desiring pregnancy. Global initiatives for the promotion and uptake of home-based dialysis are gaining momentum and may have advantages in this unique patient population. In this article, we review the epidemiology and outcomes of pregnancy in hemodialysis and peritoneal dialysis recipients. We discuss the role home-based therapies may play in helping women achieve more successful pregnancies and outline the principles and practicalities of management of dialysis in pregnancy with a focus on delivery of home modalities. The experience and perspectives of a patient are also shared.

Comparison of Breastfeeding Practices in Mothers With Chronic Kidney Disease With or Without Kidney Transplantation

Introduction: Existing literature on pregnant patients with chronic kidney disease (CKD) with or without kidney transplantation focuses mainly on their pregnancy outcomes, but there are scant data on their lactation outcomes. Our objective was to characterize the lactation outcomes of patients with CKD with or without kidney transplantation. Methods: This is a single-institution retrospective cohort study of female-identifying patients with CKD with or without kidney transplantation who had a birth hospitalization at a tertiary health system between 2010 and 2020. Maternal and pediatric data on medical history, pregnancy, delivery, neonatal, and lactation outcomes, medications, and care team involved were collected. Primary outcome measures were breastfeeding initiation within 24-hour postpartum, breastfeeding 8 or more times per day during hospitalization, and any breastfeeding beyond 1 month. Health professionals' comments related to lactation and medications were extracted for qualitative data analysis. Results: Patients with and without kidney transplantation had similar comorbidities, pregnancy, delivery, and neonatal outcomes, and hospital length of stay (p > 0.05). Patients without kidney transplantation were more likely to initiate breastfeeding in the first 24 hours (p = 0.03) after delivery and continue breastfeeding beyond 1 month postpartum. There was a lack of consistency between specialties regarding medication compatibility with lactation. Patients on immunosuppression were more likely to exclusively formula feed (p = 0.02) or to initiate breastfeeding and then switch to formula (p = 0.0004) because of their immunosuppressive medications versus patients on any other medication. Conclusion: Patients with CKD but without a kidney transplantation were more likely to initiate breastfeeding or provide breast milk to their infant within 24 hours of delivery, breastfeed >8 times per day during their hospital stay, and breastfeed beyond a month postpartum than those with a transplanted kidney. Lactation support and pharmacology should be incorporated into graduate medical education.

Efficacy and safety of hemodialysis strategies for pregnant women with chronic kidney disease: Systematic review

Pregnancy in chronic kidney disease (CKD) women is relatively rare, and the less risky choice of hemodialysis is unknown. The objective of this systematic review was to identify, systematically evaluate and summarize the available evidence on the efficacy and safety of hemodialysis strategies for pregnant CKD women. Sensitive search strategies were applied to six databases without data or language restrictions. Comparative (randomized and non-randomized) studies were prioritized. Two reviewers independently selected, extracted, and critically evaluated data from studies. The risk of bias assessment was performed using the ROBINS-I tool, considering the study design (non-randomized comparative observational studies). The certainty of the evidence was assessed using the GRADE approach. From 7210 references identified, six retrospective cohort studies were included (576 women). The effects of intensive hemodialysis (over 20 h/week) are uncertain for maternal and neonatal mortality (Peto odds ratio [OR] 0.85; 95% confidence interval [95% CI] 0.26-2.80), miscarriage (Peto OR 0, 38; 95% CI 0.12-1.23), stillbirths (Peto OR 0, 56; 95% CI 0.13-2.31), preterm birth (Peto OR 0.87; 95% CI 0.33-2.28), low birth weight (Peto OR 0.71; 95% CI 0.20-2.50) and congenital anomalies rates. The certainty of the evidence was very low due to studies methodological limitations and effect estimates imprecision. The uncertainty about intensive versus conventional hemodialysis effects for pregnant women with CKD and the imprecision in the estimated effects precludes any recommendation. The strategy choice must consider treatment availability, costs, and maternal social aspects until future studies provide more reliable evidence. PROSPERO CRD42021259237.

Parenthood with kidney failure: Answering questions patients ask about pregnancy

Achieving parenthood can be an important priority for women and men with kidney failure. In recent decades, the paradigm has shifted toward greater support of parenthood, with advances in our understanding of risks related to pregnancy and improvements in obstetrical and perinatal care. This review, codesigned by people with personal experience of kidney disease, provides guidance for nephrologists on how to answer the questions most asked by patients when planning for parenthood. We focus on important issues that arise in preconception counseling for women receiving dialysis and postkidney transplant. We summarize recent studies reflecting pregnancy outcomes in the modern era of nephrology, obstetrical, and perinatal care in developed countries. We present visual aids to help clinicians and women navigate pregnancy planning and risk assessment. Key principles of pregnancy management are outlined. Finally, we explore outcomes of fatherhood in males with kidney failure.

Should pregnant women with diabetes be counseled differently if nephropathy was detected? a population database study

INTRODUCTION

The prevalence of diabetes mellitus has increased tremendously in the last two decades among women of reproductive age and this is mainly due to the pandemic of obesity. Diabetes mellitus is a well-known cause of maternal and neonatal complications in pregnancy. Diabetic nephropathy is a marker of severe diabetes and results in organ damage. However, only a small number of studies have evaluated the implications of diabetic nephropathy on pregnancy complications, with most having 50 to 100 nephropathy subjects. Our study aims to compare pregnant women with diabetes mellitus complicated by nephropathy or not and evaluate the relationship with obstetrical and perinatal morbidity and mortality, on a larger population.

METHODS

This was a population-based study using data from the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS) including women who delivered between 2004 and 2014. Multivariate logistic regression was used to control for confounding effects.

RESULTS

Among 86,615 pregnancies that were complicated by diabetes mellitus, 1,241 (1.4%) had diabetic nephropathy. Diabetic nephropathy was strongly associated with preeclampsia (aOR 2.3, 95% CI 1.90-2.68), as well as chronic hypertension with superimposed preeclampsia or eclampsia (aOR 4.2, 95% CI 3.53-5.01), preterm birth (aOR 1.8, 95% CI 1.59-2.1), and blood transfusion (aOR 3.6 95% CI 2.82-4.46). Both groups were similar in age and income.

CONCLUSION

Diabetic nephropathy is associated with increased obstetrical and perinatal morbidity compared to diabetes mellitus alone. These patients may benefit from a high dose of folic acid, more vigilant antenatal surveillance, delivery in a tertiary care center, and more rigorous screening and prevention methods for pregnancy-induced hypertension diseases at antenatal care visits.

Determinants of perinatal outcomes in dialysed and transplanted women in Australia

Introduction

Drivers of adverse perinatal outcomes in pregnancies of women receiving chronic kidney replacement therapy (KRT) remain poorly understood.

Methods

Births ≥ 20 weeks of gestation in Australian women receiving KRT were analyzed for perinatal outcomes stratified by maternal KRT exposure (dialysis or transplant, analyzed separately), by linking the Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) and perinatal data sets (1991–2013).

Results

Of 2,948,084 babies (1,628,181 mothers), 248 were born to mothers receiving KRT (transplant, n = 211; dialysis, n = 37), with live birth rates ≥ 94%. The perinatal death rate was 162, 62, and 9 per 1000 births in the dialysis, transplant, and non-KRT cohorts, respectively. Babies exposed to KRT had increased odds of prematurity, small-for-gestational age (SGA), poor birth condition, resuscitation, intensive care admission, and longer hospitalization, with the dialysis cohort having worse outcomes. Preterm babies of dialyzed and transplanted mothers (compared with preterm babies with no KRT exposure) experienced 1.6- to 2.7-fold higher odds for all adverse outcomes, except birthweight < 2500 g, which was 11-fold higher for the dialysis cohort. In adjusted analyses, transplanted women with better allograft function (serum creatinine ≤ 120 μmol/l) still had >10-fold higher odds of preterm birth and low birthweight and 1.8- to 4.6-fold increased odds of other adverse outcomes. In transplanted women, mediation analysis revealed that pregnancy-induced hypertension contributed only a modest proportional effect (2.5%–11.2%) on adverse outcomes.

Conclusion

Maternal dialysis and transplantation conferred excess perinatal morbidity, particularly for preterm babies, and even in women with good preconception allograft function. Pregnancy-induced hypertension is not the predominant determinant of perinatal morbidity. Preconception counseling of women with kidney disease should encompass discussion of perinatal complications.

Pregnancy and CKD: Advances in Care and the Legacy of Dr Susan Hou

Dr Susan Hou began her illustrious nephrology career at a time when pregnancy in women with chronic kidney disease (CKD) was hazardous and actively discouraged. Her pioneering research in women's health provided much of the early outcome data that shaped our current understanding of CKD and pregnancy. Although many uncertainties regarding optimal management of this vulnerable patient group remain, recent decades have witnessed important advances and renewed interest in improving care for pregnant women with CKD. Many nephrologists have been inspired by Dr Hou's lifetime of work and are grateful for her generous collaborations. In this In Practice Review, we honor her legacy by providing an update of current literature and clinical management guidance in the context of a clinical case vignette that challenges us to consider the many complex aspects to the counseling and care of women with CKD who desire a pregnancy.

Ignorance is Not Bliss: The Case for Comprehensive Reproductive Counseling for Women with Chronic Kidney Disease

The bioethics literature has paid little attention to matters of informed reproductive decision-making among women of childbearing age who have chronic kidney disease (CKD), including women who are on dialysis or women who have had a kidney transplant. Women with CKD receive inconsistent and, sometimes, inadequate reproductive counseling, particularly with respect to information about pursuing pregnancy. We identify four factors that might contribute to inadequate and inconsistent reproductive counseling. We argue that women with CKD should receive comprehensive reproductive counseling, including information about the possibility of pursuing pregnancy, and that more rigorous research on pregnancy in women with CKD, including women on dialysis or who have received a kidney transplant, is warranted to improve informed reproductive decision making in this population.

Pregnancy and delivery in women receiving maintenance hemodialysis in Japan: analysis of potential risk factors for neonatal and maternal complications

Introduction

Average dialysis vintage in Japan is among the longest in the world, providing a unique opportunity to characterize pregnancy under conditions of long dialysis vintage. In 2017, we carried out a nationwide survey following up on a similar survey in 1996, in which we investigated the prevalence and outcomes of pregnancy in women undergoing dialysis and assessed risk factors associated with neonatal and maternal complications.

Methods

The target population was women aged 15–44 years undergoing maintenance dialysis between 2012 and 2016. The survey was conducted in 2693 dialysis units.

Results

A response was obtained from 951 dialysis units, yielding a target population of 1992 women of childbearing age receiving hemodialysis or peritoneal dialysis. Pregnancy occurred only among women receiving hemodialysis, with 25 pregnancies (1.26% in 5 years) being reported for 20 women. Detailed information about 19 pregnancies (mean age 34.6 ± 5.7 years at conception, mean dialysis vintage 8.4 ± 7.3 years) indicated 4 spontaneous abortions, 1 elective abortion, no neonatal deaths, and 14 surviving infants, including 5 full-term (≥ 37 weeks at birth), 2 late preterm (34–36), and 3 extremely preterm (< 28) cases. Neonatal complications occurred in the offspring of 3 mothers who had end-stage renal disease (ESRD) caused by primary glomerulonephritis and serum albumin levels (sAlb) ≤ 3.2 mg/dL in the first trimester. These mothers had started dialysis at 12, 17, and 30 years of age. ESRD caused by diabetic nephropathy or primary glomerulonephritis, age at conception ≥ 38 years, and sAlb ≤ 3.2 mg/dL were associated with maternal complications, although not significantly.

Conclusions

In this study, the pregnancy rate of Japanese women with ESRD was 0.25% per year. The study generates the hypothesis that ESRD caused by diabetic nephropathy and age at conception ≥ 38 years are potential risk factors for maternal complications but not for neonatal complications in dialysis patients, and that hypoalbuminemia is a potential risk factor for both kinds of complications.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s40620-021-01146-3.

Factors influencing fertility rates in Australian women receiving kidney replacement therapy: Analysis of linked ANZDATA registry and perinatal data over 22 years

BACKGROUND

Pregnancy in women receiving kidney replacement therapy (KRT) is uncommon, and trends and factors influencing fertility rates remain poorly defined.

METHODS

The Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) was linked to mandatory perinatal datasets (all births from 1991-2013, ≥20 weeks' gestation) in four Australian jurisdictions. Overall, age and era-specific fertility rates were calculated based on general and KRT population denominators.

RESULTS

From 2,948,084 births, 248 babies were born to 168 mothers receiving KRT (37 babies born to 31 dialysed mothers; 211 babies born to 137 transplanted mothers). Substantial agreement between ANZDATA and perinatal datasets was observed for birth events and outcomes. Transplanted women had higher fertility rates than dialysed women in all analyses, with 21.4 live births/1000 women/year (95% CI: 18.6-24.6) in transplanted women, 5.8 (95% CI: 4.1-8.1) in dialysed women and 61.9 (95% CI: 61.8-62.0) in the Non-KRT cohort. Fertility rates for dialysed women rose in recent years. After adjusting for maternal age and treatment modality, Caucasian women had higher fertility rates, while women with pre-existing diabetes, or transplanted women with exposure to KRT for ≤3.0 years had lower rates. As expected, transplanted women with a pre-conception estimated glomerular filtration rate (eGFR) of < 45 or transplant-to-pregnancy interval of < 1.0 year had lower fertility rates. Geographical location, socioeconomic status and primary disease (glomerulonephritis vs. other) did not affect fertility rates.

CONCLUSIONS

Reporting of births to ANZDATA is sufficiently accurate to justify ongoing data collection. Rising fertility rates in dialysed women may indicate permissive attitudes towards pregnancy. Treatment modality, ethnicity, diabetes, pre-conception eGFR, transplant-to-pregnancy interval and duration of KRT exposure were associated with fertility rates. These factors should be considered when counselling women with kidney disease about parenthood.

Fertility and Pregnancy in End Stage Kidney Failure Patients and after Renal Transplantation: An Update

Sexual life and fertility are compromised in end stage kidney disease both in men and in women. Successful renal transplantation may rapidly recover fertility in the vast majority of patients. Pregnancy modifies anatomical and functional aspects in the kidney and represents a risk of sensitization that may cause acute rejection. Independently from the risks for the graft, pregnancy in kidney transplant may cause preeclampsia, gestational diabetes, preterm delivery, and low birth weight. The nephrologist has a fundamental role in correct counseling, in a correct evaluation of the mother conditions, and in establishing a correct time lapse between transplantation and conception. Additionally, careful attention must be given to the antirejection therapy, avoiding drugs that could be dangerous to the newborn. Due to the possibility of medical complications during pregnancy, a correct follow-up should be exerted. Even if pregnancy in transplant is considered a high risk one, several data and studies document that in the majority of patients, the long-term follow-up and outcomes for the graft may be similar to that of non-pregnant women.

Sexual Dysfunction in Women With Kidney Disease

Sexual health is inversely associated with estimated glomerular filtration rate and is associated with adverse cardiovascular outcomes, depression, poor self-image, and impaired quality of life. Many women with chronic kidney disease (CKD) and ESKD experience symptoms of sexual dysfunction which is underrecognized secondary to a variety of factors including physicians' discomfort in discussing sexual health, patients' reluctance to bring up sexual health, difficulty in the assessment of sexual health in comparison to men, and the overall lack of well-conducted clinical studies in women. The pathophysiology is not fully understood but likely involves changes in sex hormones throughout the hypothalamic-pituitary-ovarian axis. Proper evaluation of this axis is necessary as treatment is tailored to these findings and can improve outcomes. A comprehensive assessment of sexual dysfunction inclusive of women with varying gender identification and sexual orientation, partnered with recognition and treatment of contributing factors as well as identifying the underlying cause, is paramount. With the lack of studies, particularly in women with CKD, treatment options, in some cases, can be considered unchartered territory. In this article, we will review available evidence on the pathophysiology, clinical manifestations, and treatment for sexual dysfunction in women with CKD and ESKD.

End-Stage Kidney Disease and Dialysis in Pregnancy

End-stage kidney disease is associated with low fertility, with rates of conception in women on dialysis estimated at 1/100th of the general population. However, live birth rates are increasing over time in women on hemodialysis, whereas they remain lower and static in women on peritoneal dialysis. Intensification of hemodialysis, targeting a serum blood urea nitrogen <35 mg/dL or 36 hours of dialysis per week in women with no residual kidney function, is associated with improved live birth rates and longer gestational age. Even in intensively dialyzed cohorts, rates of prematurity and need for neonatal intensive care are high, upwards of 50%. Although women on peritoneal dialysis in pregnancy do not appear to be at increased risk of delivering preterm compared with those on hemodialysis, their infants are more likely to be small for gestational age. As such, hemodialysis has emerged as the preferred dialysis modality in pregnancy. Provision of specialized nephrology, obstetric, and neonatal care is necessary to manage these complex pregnancies and family planning counseling should be offered to all women with end-stage kidney disease.

Chronic Kidney Disease and Pregnancy

Women with chronic kidney disease (CKD) are at high risk for adverse outcomes in pregnancy. In the United States, pregnancy rates in women with risk factors for CKD such as obesity and advanced maternal age are increasing; thus, more pregnancies are likely to be affected by CKD. Strategies that involve coordinated multidisciplinary care to optimize preconception health, perform meticulous antenatal monitoring, and provide continued care in the postpartum "fourth trimester" appear to be most beneficial for both the mother and baby. Discussions surrounding preconception risk stratification should be individualized based on CKD stage/serum creatinine level, degree of hypertension and proteinuria, and comorbid conditions. Preparation for pregnancy should include optimization of comorbidities and medication adjustments to those compatible with pregnancy. Unless contraindicated, all women with CKD should be prescribed low-dose aspirin in pregnancy to reduce risk of preeclampsia. After delivery, women with CKD may benefit from an early postpartum visit (within 7-10 days) for blood pressure check and may require serial monitoring of serum creatinine and proteinuria as appropriate. Breastfeeding is safe and can be recommended for most women with CKD. A contraceptive plan that includes patients' preferences, feasibility, medical eligibility, duration, and effectiveness of the contraceptive method should be implemented.

Exclusion of pregnancy in dialysis patients: diagnostic performance of human chorionic gonadotropin

Background

A positive pregnancy test in acute or chronically ill patients has implications for the use of potentially mutagenic or teratogenic products in urgent medical therapies such as the use of chemotherapies or therapies with immunosuppressants, for anesthesia, and for time-sensitive indications like urgent surgery or organ Transplantation.

Despite a lack of evidence, it is currently believed that human chorionic gonadotropin serum concentrations are always elevated in female dialysis patients even without pregnancy. It is also believed that human chorionic gonadotropin cannot be used to confirm or exclude pregnancy.

Methods

Human chorionic gonadotropin was examined in female dialysis patients (18–50 years of age), and was classified as positive above 5 mlU/ml. In addition, fertility status was determined. For an enhanced index test, the cut-off of 5 mIU/ml was used for potentially fertile patients and 14 mIU/ml for infertile patients to calculate diagnostic test accuracy. The ideal cut-off for human chorionic gonadotropin was estimated using Liu’s method with bootstrapped 95% confidence intervals. Predictors of human chorionic gonadotropin increase were analyzed using multivariable linear regression.

Results

Among 71 women, two (2.8%) were pregnant, 46 (64.8%) potentially fertile, and 23 (32.4%) infertile. We observed human chorionic gonadotropin concentrations > 5 mIU/ml in 10 patients, which had a sensitivity of 100% (95% confidence interval: 100 to 100), a specificity of 86% (95% confidence interval: 77 to 94), a positive predictive value of 17% (95% confidence interval: 8 to 25) and a negative predictive value of 100% (95% confidence interval: 100 to 100) for the diagnosis of pregnancy. Using a cut-off > 14 mIU/ml for infertile patients or the exclusion of infertile patients increased specificity to 93% or 98%, respectively. The ideal cut-off was 25 mIU/ml (95% confidence interval: 17 to 33). Pregnancy and potential fertility, but not age, were independent predictors of human chorionic gonadotropin.

Conclusion

Human chorionic gonadotropin is elevated > 5mIU/ml in 14.5% of non-pregnant dialysis patients of child-bearing age. In potentially fertile women, this cut-off can be used to exclude pregnancy. In case of an unknown fertility status, the ideal human chorionic gonadotropin cut-off was 25 mIU/ml.