Elements in High Risk Pregnancy: Management Options – serie

Sixty years ago, the purpose of introducing electronic fetal heart rate monitoring (EFM) was to reduce the incidence of intrapartum stillbirth. However, by the early 1980s, with falling stillbirth rates, fetal blood sampling had been widely abandoned, as many considered that EFM was sufficient on its own. Unfortunately, while the sensitivity of EFM for the detection of potential fetal compromise is high, specificity is low, and there is a high false positive rate which has been associated with a rising cesarean section rate. The authors suggest that EFM is considered and analyzed as a classic screening test and not a diagnostic test. Furthermore, it requires contextualization with other risk factors to achieve improved performance. A new proposed metric, the Fetal Reserve Index, takes into account additional risk factors and has demonstrated significantly improved performance metrics. It is going through the phases of further development, evaluation, and wider clinical implementation.

Caesarean section delivery (CD) is the most common surgical operation performed in the world. Since first described 400 years ago, surgical rates continue to rise globally. Caesarean rates are now reported from South American countries of over 50% and rates of over 32% are currently being reported from the United States, China, England and Scotland. Surgical complications can occur at the time of operation and there are major implications for future pregnancies, including increased rates of placenta previa/accreta, stillbirth and preterm labour. This Element discusses many aspects of CD, including the Robson 10 group classification system, which classifies populations by characteristics such as parity, presentation of the fetus and the history of previous births, an evidencebased approach to surgical techniques, recommendations of the major guidelines and recommendations concerning trial of labour after previous caesarean.

Diabetes mellitus is one of the most common and important medical complications affecting pregnancy. It can predate the pregnancy ('pre-existing diabetes') or arise during pregnancy ('gestational diabetes', GDM). Typically, GDM resolves once the pregnancy has ended. However, about 3% of women with a diagnosis of GDM have type 2 diabetes diagnosed for the first time in pregnancy, which persists beyond pregnancy. The coexistence of diabetes of any type and pregnancy is associated with an increased risk of adverse outcomes for both the woman and baby. However, with appropriate management by a multidisciplinary team before, during and after delivery these risks can be minimised. Optimising blood glucose control, screening for maternal and fetal complications and a discussion about delivery are key strategies. During pregnancy, all women should be offered screening for GDM. After pregnancy, all women with GDM should be offered annual screening to identify the development of type 2 diabetes.

Spontaneous preterm birth remains the leading cause of neonatal death, and the second leading cause of mortality worldwide in children below five years of age. The causes of preterm birth are multifactorial, likely contributing to why significant progress in reducing the incidence has been slow. This Element contains the most up-to-date evidence regarding the aetiology, epidemiology, and management of pregnancies at risk of, or complicated by, spontaneous preterm birth and preterm pre-labour rupture of membranes. It concentrates largely on those aspects potentially amenable to preventative intervention (i.e. cervical dysfunction and premature uterine contractility), as well as strategies to improve outcomes for infants born prematurely.

Mental health disorders are common in pregnancy and after childbirth with over 10% of women manifesting some form of mental illness during this time. Maternity services will encounter women with symptoms that vary in severity from mild self-limiting to potentially life-threatening. These conditions carry risks for both the woman and the fetus/newborn. Detecting women with, or at risk of, a serious mental health disorder and enabling them to access appropriate care in a timely fashion is a shared responsibility. However, given the frequency of contact they have with women through this period, maternity services have a pivotal role. From a mental health perspective, high-risk pregnancies are those primarily associated with serious mental illness (psychotic illnesses, bipolar disorder and severe depressive episodes). Healthcare professionals caring for pregnant women should have the appropriate skills to detect serious mental illness and identify women at risk and how to access specialist mental health care.

Multiple pregnancy affects 0.9-3.1% of births worldwide. Prevalence rates vary significantly due to differences in dizygotic twinning rates and use of assisted reproduction. Both maternal and fetal/neonatal complications are more common in multiple compared to singleton pregnancies, and there are specific problems for the fetuses related to monochorionicity. Multiple pregnancies require specialised and individualised care. Complicated multiple pregnancies should be managed in a tertiary care centre where there is additional expertise, such as the laser ablation needed to treat monochorionic monozygotic pregnancies with conjoined circulations. Cornerstones of management in pregnancy are the need for accurate fetal measurement to optimise dating of gestational age, and documentation of chorionicity. High-level ultrasound expertise is needed. The mothers need frequent assessment to detect hypertension and anemia, and early identification and management of preterm labour.

Cardiac disease complicating pregnancy is present in a relatively small number of women; however, it accounts for a disproportionate share of maternal morbidity and mortality, especially in developing/emerging countries. The prevalence of cardiac disease in pregnancy is increasing and there are multiple underlying etiologies with wide-ranging severity. Normal adaptions during pregnancy often further challenge already compromised anatomic and physiologic compensatory mechanisms of the cardiovascular system, increasing the risk of adverse maternal and fetal outcomes. In this Element, the authors describe how these changes alter nonpregnant physiology with a variety of preexisting and newly diagnosed cardiac conditions. Maternal and fetal risks are reviewed. Diagnosis and management, from before conception through the postpartum period including appropriate contraception, is discussed. The goal of this review is to increase understanding of the importance of cardiac disease in pregnancy and encourage high-quality multidisciplinary care, and thus improve maternal and fetal outcomes.

Stillbirth, especially unpredicted losses in the antepartum period defined as intrauterine fetal demise after twenty weeks gestation, remains sadly a too common event during pregnancy. Dr. Gandhi and Professor Reddy detail the epidemiology and review the impact of proactive interventions both in preparation for and during pregnancy to lower stillbirth rates. The clinical management of a pregnancy affected by this tragedy. The authors address a growing understanding of causes seen clinically and those unseen (e.g. genetic abnormalities, viral infection, fetal hypoxia in a normally grown fetus, etc). The detailed approach to stillbirth during the index pregnancy seeks to maximize the discovery of the underlying causes to provide solace to the grieving family and to prepare for any additions to prenatal care for any subsequent pregnancies.