Effect of Maternal Cystic Fibrosis Genotype on Diabetes in Pregnancy:

Pregnancy and fertility in people with cystic fibrosis following lung transplantation

PURPOSE OF REVIEW

The purpose of this review is to summarize available data on fertility, fertility preservation, pregnancy and parenthood following lung transplantation for people with cystic fibrosis (pwCF).

RECENT FINDINGS

In the era of cystic fibrosis transmembrane conductance regulator (CFTR) modulator use, oral therapies that positively impact fundamental CFTR protein abnormalities, the number of pregnancies has increased dramatically with a concomitant decrease in lung transplantation. Nonetheless, some pwCF still require lung transplantation as a life-saving measure, and a fraction of those individuals desires parenthood. Cystic fibrosis (CF) providers infrequently discuss fertility preservation with pwCF, and pwCF feel uneducated about their fertility options posttransplant. However, because the immunosuppression required to successfully maintain lung allografts may impact future fertility, pwCF should receive genetic and reproductive counseling prior to lung transplantation. While pregnancies posttransplantation are high-risk, selected females with CF may be able to pursue this path to parenthood.

SUMMARY

Although there is a paucity of data specific to pwCF who have undergone lung transplantation, recently developed general guidelines should inform discussions regarding fertility, pregnancy and parenthood in pwCF who desire parenthood following lung transplantation for optimal shared decision-making.

Pregnancy in women with cystic fibrosis and diabetes: An audit of outcomes at two tertiary obstetric hospitals in Australia in the pre-cystic fibrosis transmembrane conductance regulator modulator era

Background

Pregnancy in women with cystic fibrosis (CF) is becoming more common. Long-term metabolic issues such as diabetes are also becoming more common and have potentially important impacts on pregnancy outcomes. This study aimed to assess the impact of diabetes on pregnancy outcomes for women with CF.

Methods

We undertook a retrospective chart audit of pregnancies to women with CF at the two tertiary obstetric hospitals in Southeast Queensland associated with CF and transplant management clinics between 2006 and 2016.

Results

A total of 38 pregnancies among 26 women were identified. Four women (five pregnancies) had cystic fibrosis-related diabetes (CFRD) diagnosed prior to pregnancy, and 12 women (15 pregnancies) developed gestational diabetes (GDM) complicating pregnancy. CFRD and GDM were associated with higher rates of delivery complications, prematurity, and the need for neonatal intensive care unit admission.

Conclusion

Diabetes is common during pregnancy in women with CF and impacts pregnancy outcomes.

Screening strategies for glucose tolerance abnormalities and diabetes in people with cystic fibrosis

The increase in life expectancy of patients with cystic fibrosis has come with new comorbidities, particularly diabetes. The gradual development of glucose tolerance abnormalities means that 30 to 40% of adults will be diabetic. Cystic fibrosis-related diabetes is a major challenge in the care of these patients because it is a morbidity and mortality factor at all stages of the disease. Early glucose tolerance abnormalities observed from childhood, before the stage of diabetes, are also associated with a poor pulmonary and nutritional outcome. The long asymptomatic period justifies systematic screening with an annual oral glucose tolerance test from the age of 10 years. However, this strategy does not take into account the new clinical profiles of patients with cystic fibrosis, recent pathophysiological knowledge of glucose tolerance abnormalities, and the emergence of new diagnostic tools in diabetology. In this paper, we summarise the challenges of screening in the current context of new patient profiles - patients who are pregnant, have transplants, or are being treated with fibrosis conductance transmembrane regulator modulators - and put forward an inventory of the various screening methods for cystic fibrosis-related diabetes, including their applications, limitations and practical implications.

Gestational and pregestational diabetes in pregnant women with cystic fibrosis

As cystic fibrosis transmembrane regulator (CFTR) modulator therapies offer greater longevity and improved health quality, women living with cystic fibrosis (CF) are increasingly pursuing pregnancy. Maternal risks for pregnant women with CF largely depend on a woman's baseline pulmonary and pancreatic function, and the majority of CF pregnancies will successfully end in live births. Diabetes, either gestational or pre-existing cystic fibrosis-related diabetes (CFRD), is highly prevalent in women with CF, affecting 18 to 62% of pregnancies in recent CF center reports. In addition to the rising incidence of CFRD with age, gestational diabetes is also more common in women with CF due to lower insulin secretion, higher insulin resistance, and increased hepatic glucose production as compared to pregnant women without CF. Diabetes occurring during pregnancy has important implications for maternal and fetal health. It is well established in women without CF that glycemic control is directly associated with risks of fetal malformation, neonatal-perinatal mortality, cesarean delivery and need for neonatal intensive care. Small studies in women with CF suggest that pregnancies affected by diabetes have an increased risk of preterm delivery, lower gestational age, and lower fetal birth weight compared to those without diabetes. Women with CF preparing for pregnancy should be counseled on the risks of diabetes and should undergo routine screening for CFRD with oral glucose tolerance testing (OGTT) if not already completed in the past six months. Glycemic control in those with pre-gestational CFRD should be optimized prior to conception. Insulin is preferred for the management of diabetes in pregnant women with CF via multiple daily injections or insulin pump therapy, and continuous glucose monitors (CGM) can be useful in mitigating hypoglycemia risks. Women with CF face many unique challenges impacting diabetes care during pregnancy and would benefit from support by a multidisciplinary care team, including nutrition and endocrinology, to ensure healthy pregnancies.

Pregnancy in cystic fibrosis: Review of the literature and expert recommendations

Cystic fibrosis (CF) was historically a disease largely afflicting children. Due to therapeutic advancements, there are now more adults with CF than children. In the past decade, medications including Cystic Fibrosis Transmembrane conductance Regulator (CFTR) modulators became available that treat the underlying cause of CF and are dramatically improving lung function as well as quality and quantity of life for people with CF. As a result, more women with CF are becoming pregnant. We gathered a panel of experts in CF care, family planning, high risk obstetrics, nutrition, genetics and women with CF to review current literature on pregnancies and to provide care recommendations for this unique population.

[Cystic fibrosis and pregnancy: Outcome, prognostic factors and obstetrical management]

As a result of improvements in life expectancy and therapies, increasing numbers of patients with cystic fibrosis become pregnant. The first studies were pessimistic and report adverse outcomes on the fetus and the mother. In the recent publications, long-term outcome for women with cystic fibrosis does not appear to be negatively impacted by pregnancy. Furthermore, the number of women successfully completing pregnancy continues to rise. The aim of this review is to assess the outcome of pregnancy in women with cystic fibrosis and the impact of pregnancy on the disease. It is hoped it will improve the counseling for pregnant women with cystic fibrosis and their obstetrical management.

Maternal co-morbidities and neonatal outcomes associated with cystic fibrosis. J Matern Fetal Neonatal Med 2016;30:4-7. [PMID: 26940249 DOI: 10.3109/14767058.2016.1161747]

OBJECTIVE

To evaluate maternal co-morbidities and adverse perinatal outcomes associated with cystic fibrosis (CF).

METHODS

This is a retrospective cohort study of 2 178 954 singleton pregnancies at ≥20 weeks' gestation with and without CF in the state of California during the years 2005-2008. ICD-9 codes and linked hospital discharge and vital statistics data were utilized. Rates of maternal co-morbidities, fetal congenital anomalies and adverse perinatal outcomes were compared in those with CF and those without. Maternal co-morbidities included gestational hypertension, preeclampsia, gestational diabetes and primary cesarean delivery. Perinatal outcomes included neonatal demise, preterm birth, intrauterine growth restriction, macrosomia, anomaly, fetal demise, asphyxia, respiratory distress syndrome, jaundice, intraventricular hemorrhage, hypoglycemia and necrotizing enterocolitis.

RESULTS

The cohort included 2 178 954 pregnancies of which 77 mothers had CF. Mothers with CF were more likely to have pre-gestational diabetes and had higher rates of primary cesarean delivery. Neonates delivered to mothers with CF were more likely to be born preterm and have congenital anomalies but otherwise were not at increased risk for significant neonatal morbidity or mortality when adjusted for gestational age.

CONCLUSION

Mothers with CF are more likely to have pre-gestational diabetes, deliver preterm (<37 weeks gestation) and have a primary cesarean delivery. Infants are more likely to have congenital anomalies. In addition to early diabetic screening and genetic counseling, a detailed fetal anatomy ultrasound should be performed in women with CF.