The current models of obstetric medical care utilized in the United States, how those models fit in with the overall care system, and ways to increase the role of obstetric internists will be reviewed.
This article summarizes and critiques four recent publications looking at preconception counseling, pregnancy outcomes, and cardiac complications in women with history of Fontan circulation. The Fontan procedure is a palliative strategy for single-ventricle type congenital heart disease and involves passive flow of venous return into the pulmonary circulation, bypassing the ventricles. Pregnancy in these patients is not without risk and preconception counseling and contraception practices vary widely. High rates of miscarriage, prematurity, and small-for-gestational-age babies are reported. Cardiac complications include mainly arrhythmias. Whether long-term prognosis in these patients is affected by pregnancy is not yet known.
Pregnant women receiving low-molecular-weight heparin for therapeutic anticoagulation are often converted to unfractionated heparin in anticipation of labor. We aim to characterize the impact of maternal body mass index on attainment of target anticoagulation during the conversion process.
We conducted a five-year retrospective study of a pregnancy cohort converted from low-molecular-weight heparin to unfractionated heparin in the third trimester. Patient demographics, anticoagulation regimens, and clinical outcomes were extracted from the medical record. Nonparametric statistical methods were used for analysis by body mass index (<30, 30–35, and >35).
Thirty-one subjects were evenly distributed by body mass index (p = 0.97). Linear regression revealed an inverse correlation between patient body mass index and unfractionated heparin dose needed to achieve therapeutic anticoagulation (p = 0.04). Subjects with body mass index > 35 attained therapeutic activated partial thromboplastin time levels at 18 U (Units)/kg/h, while subjects with body mass index < 30 required 25 U/kg/h (p = 0.02).
Higher doses of unfractionated heparin are needed to achieve anticoagulation in patients with body mass index < 30 during pregnancy. This paradoxical relationship may be explained by physiologic characteristics that increase unfractionated heparin elimination, including diminished adiposity and increased renal clearance.
Pulmonary hypertension is associated with 36% mortality in pregnancy, and 6–10% of patients with sickle cell disease have pulmonary hypertension. Tricuspid regurgitant velocity ≥2.5 m/s on echocardiography is a well validated means of screening for pulmonary hypertension in the non-pregnant population. This is a pilot study to determine if this is a useful non-invasive screening test for pulmonary hypertension in pregnancy, and whether raised tricuspid regurgitant velocity ≥2.5 m/s was associated with poor outcomes. This is a cross-sectional study over a five-year period in a tertiary referral centre with a specialised multidisciplinary clinic for pregnant women with sickle cell disease. Women with sickle cell disease, no prior pulmonary hypertension and singleton pregnancies who had echocardiography with a measurable tricuspid regurgitant velocity in pregnancy were included. There were 34 pregnancies, of which eight had tricuspid regurgitant velocity ≥2.5 m/s. There were no significant differences in their characteristics, sickle cell-related complications or medical co-morbidities. The women with tricuspid regurgitant velocity ≥2.5 m/s had similar obstetric and perinatal outcomes as those with a tricuspid regurgitant velocity <2.5 m/s.
The rapid global uptake of noninvasive prenatal testing for Down syndrome based on maternal plasma cell-free DNA has provided new data on the interrelationship between cell-free DNA and maternal health. Specific maternal conditions that can affect the performance of noninvasive prenatal testing include obesity, active autoimmune disease and low molecular weight heparin treatment. There is also a growing appreciation of the implications of discordant noninvasive prenatal testing results for maternal health, including unexpected diagnoses of maternal chromosomal conditions, or rarely, occult cancer. The interrelatedness of noninvasive prenatal testing and maternal health mean that the longstanding principles underpinning prenatal screening – voluntary testing, informed decision making, availability of specialist genetic counselling and well-defined clinical pathways – are more important than ever before.
Oxidative stress is implicated in the pathophysiology of many reproductive complications including infertility, miscarriage, pre-eclampsia, fetal growth restriction and preterm labour. The presence of excess reactive oxygen species can lead to cellular damage of deoxyribonucleic acids, lipids and proteins. Antioxidants protect cells from peroxidation reactions, limiting cellular damage and helping to maintain cellular membrane integrity. There is overwhelming evidence for oxidative stress causing harm in reproduction. However, there is sparse evidence that supplementation with commonly used antioxidants (mostly vitamins C and E) makes any difference in overcoming oxidative stress or reversing disease processes. There may be potential for antioxidant therapy to ameliorate or prevent disease, but this requires a thorough understanding of the mechanism of action and specificity of currently used antioxidants.
The commercial availability of tests in the first trimester of pregnancy that predict the later development of pre-eclampsia has prompted considerable debate regarding their clinical utility and the degree to which they fulfil the longstanding principles of screening. Such tests have been shown to achieve detection rates for early pre-eclampsia (requiring delivery prior to 34 weeks) of over 90%, for a false positive rate of 10%. However, their capacity to predict later onset pre-eclampsia, which accounts for the bulk of the disease burden, is much more limited. The relatively few studies validating the performance of these tests in different populations have demonstrated significant variations in performance. Moreover, prospective research confirming that the administration of aspirin to those screened to be high risk reduces the incidence of pre-eclampsia is yet to be completed, and there may be harms in restricting aspirin therapy to this group, given its broader beneficial effect. In light of these limitations, further development of these tests is recommended prior to their introduction to clinical practice.
Obstetric medicine is a growing area of interest within internal medicine in Canada. Canadians continue to travel broadly to obtain relevant training, particularly in the United Kingdom. However, there is now a sufficient body of expertise in Canada that a cadre of ‘home-grown’ obstetric internists is emerging and staying within Canada to improve maternity care. As this critical mass of practitioners grows, it is apparent that models of obstetric medicine delivery have developed according to local needs and patterns of practice. This article aims to describe the state of obstetric medicine in Canada, including general internal medicine services as the rock on which Canadian obstetric medicine has been built, the Canadian training curriculum and opportunities, organisation of obstetric medicine service delivery and the future.
Pregnant women with venous thromboembolism are traditionally managed with anticoagulation, but inferior vena cava filters are an alternative. We balanced risks and benefits of an inferior vena cava filter in a decision analysis.
We constructed a decision model to compare in pregnant women with VTE the outcome of (1) inferior vena cava filter and anticoagulant treatment versus (2) anticoagulant treatment only.
Assuming a 63% risk reduction from an inferior vena cava filter (baseline mortality rate of venous thromboembolism of 0.5%), 318 women would need to be treated with inferior vena cava to prevent one venous thromboembolism related maternal death. Sensitivity analyses indicated that at a mortality rate of 0.5% the risk reduction from inferior vena cava needed to be 80%, while at a mortality rate of 2% a risk reduction of 20% would justify inferior vena cava.
In view of their potential morbidity, inferior vena cava filters should be restricted to pregnant woman at strongly increased risk of recurrent venous thromboembolism.
Scrub typhus is an important unrecognized cause for undifferentiated acute febrile illness in India associated with poor fetal outcomes. Maternal and fetal outcomes among pregnant patients with scrub typhus presenting to a tertiary care university teaching hospital from January 2010 to July 2012 were studied. Scrub typhus was diagnosed by clinical criteria along with scrub ELISA positivity or an eschar. In total, 33 of 738 patients (4.5%) who were diagnosed with scrub typhus were pregnant; 57.6% were in the third trimester, 27.3% in the second, and only 15.2% in the first trimester; 69.7% required admission to intensive care. Mortality was low (3%, n = 1) compared to 12.2% mortality reported previously. All patients were treated with Azithromycin. Poor fetal outcome was observed in 51.5% of these pregnancies with fetal loss occurring in 42.4% and preterm childbirth in 9.1%. Scrub typhus complicating pregnancy is associated with a poor fetal outcome despite treatment with Azithromycin. A majority require intensive care treatment for survival.
To compare pregnancy care, maternal and neonatal outcomes of women with Body Mass Index (BMI) >30 enrolled in a Weight Intervention Group versus other models of antenatal care.
Retrospective, case-control study of mothers with BMI >30 managed with a specialised programme versus age-matched women enrolled in standard models of care.
One thousand, one hundred and fifteen of 9954 pregnant women with singleton pregnancies, had a BMI >30, of whom 9.6% enrolled in the intervention group. Compared to controls, the intervention group had superior implementation of local high BMI guidelines, including; nutritional /weight gain advice (86% vs. 46%, p < 0.001), regular weighing (80% vs. 33%, p < 0.001), lactation consultant referrals (8% vs. 1%, p = 0.02), third trimester anaesthetic review and ultrasound (50% vs. 20.9%, p = 0.04 and 55% vs. 43%). Initiation of breastfeeding was higher in the intervention group (100% vs. 90%, p = 0.001). No significant difference was noted in Caesarean rate (30% vs 32%) and birthweight (3538 g vs 3560 g).
Women with high BMI enrolled in a specialised antenatal management programme received increased care, and had superior breastfeeding initiation rates. However, engagement was poor, and no significant differences were noted in antenatal or postnatal complications, mode of birth or neonatal outcome.
Product information is a popular medicines information resource; however, there is some evidence that its pregnancy and lactation information is overconservative, which can lead to inadequate treatment of pregnant and lactating women.
A thorough analysis of pregnancy and lactation information within Australian Product Information and Consumer Medicines Information was performed. The statements within these resources were compared with established clinical resources: Australian Medicines Handbook, Therapeutic Guidelines, South Australian Perinatal Practice Guidelines, Organization of Teratology Information Specialists, LactMed, Motherisk and the Pregnancy and Breastfeeding Medicines Guide published by the Royal Women’s Hospital Melbourne.
Product Information was found to be the most cautious resource, with 44.5% of pregnancy recommendations and 69% of lactation recommendations reviewed being more conservative than other resources.
Product Information is an imperfect and often overconservative reference for pregnant and lactating women. Health professionals are urged to review established clinical resources to inform decision making.
First-trimester care of maternal thyroid dysfunction has previously been shown to be poor. This study evaluates early management of thyroid dysfunction in pregnancy in Australia.
Patients reviewed by the Obstetric Medicine team for thyroid dysfunction from 1 January 2012 to 30 June 2013 were included. Data were collected on gestation at referral from the patient’s general practitioner to the antenatal clinic, information provided in the referral letter, thyroid function tests and thyroid medications.
Eighty-five women were included in the study. At the time of general practitioner referral to antenatal services, 19% of women with preexisting thyroid disease had no thyroid function tested. Forty-three percent had an abnormal thyroid-stimulating hormone defined as being outside the laboratory-specific pregnancy reference range if available, or outside the level of 0.1–2.5 mIu/L in the first trimester, 0.2–3.0 mIu/L in the second trimester and 0.3–3.0 mIu/L in the third trimester. Only 21% of women increased their thyroxine dose prior to their first antenatal clinic review.
This study highlights that a significant proportion of women with known thyroid disease either have untested thyroid function in the first trimester or a thyroid-stimulating hormone outside of levels recommended by guidelines.
The last few years have witnessed a number of publications linking sleep disordered breathing to adverse pregnancy and neonatal outcomes in various populations. Associations with preeclampsia, gestational diabetes and growth restriction have been consistent across many studies. Though the manuscripts reviewed here consist mostly of preliminary data and need further confirmation, the studies have highlighted new directions in the assessment of the impact of sleep disordered breathing and pregnancy, and paved the way for new fields of research in this area.
We conducted a National survey between February and June 2012 to evaluate the practices concerning screening, diagnosis and management of Gestational Diabetes (GDM) in England.
A total of 102/126 (80%) maternity units responded. The National Institute of Health and Clinical Excellence (NICE) recommended screening criteria were used by 83% of units. All the units performed 2 h 75 g oral glucose tolerance test (OGTT) between 24 and 28 weeks. There was a wide variation in the diagnostic blood glucose values used by different units. About 86% of units used a 2 h blood glucose value of ≥7.8 mmol/l and 45% of units used fasting value ≥6.1 mmol/l to diagnose GDM. Only 26% of units advised self-monitoring of blood glucose pre meal and 1 h post-meal, whereas 64% of units advised monitoring 2 h after the meal. Metformin was started when women did not respond to dietary measures in 101 units (99%). Regular growth scans every four weeks from 28 weeks onwards were performed by 99 units (97%). Women on metformin with no complications were offered induction of labour at 38 completed weeks in 97 units (95%). 84 maternity units (82.3%) offered OGTT six weeks postnatally.
Our survey has shown consistency in screening using the NICE criteria, use of 2 h 75 g OGTT at 24–28 weeks, in providing dietary support, use of metformin and ultrasound for fetal growth. But there is wide variation in the criteria used to diagnose GDM, self-monitoring of blood glucose, induction of labour and six weeks postnatal testing.
The reduction of human immunodeficiency virus (HIV) transmission from mother to child is one of the success stories of modern medicine and public health. In the developed world, with universal HIV counseling and testing, antiretroviral prophylaxis, scheduled Caesarean delivery if indicated, and avoidance of breastfeeding, HIV transmission from mother to infant can be <2%. Despite this, transmissions continue to occur, often due to lack of knowledge of HIV status. Missed opportunities for prevention and prevention challenges include late prenatal care, lack of HIV testing in pregnancy, lack of preconception counseling, unintended pregnancy, and substance abuse. We review preconception counseling including options for serodiscordant couples, and antepartum, peripartum and postpartum care of the HIV-infected woman in the developed world, and advocate for a comprehensive, collaborative, multidisciplinary approach.
Postpartum screening for diabetes in women with gestational diabetes (GDM) improves with use of reminder systems. Our primary objective was to identify predictors of diabetes screening in the first year after delivery.
A retrospective study was performed of 556 women with GDM who received outpatient prenatal care between 2007 and 2009. A mailed reminder system was utilized at two sites. Rates of postpartum glucose testing at 6 and 12 months postpartum were measured.
Site of care and non-smoking status were identified as the only predictors of postpartum diabetes screening (p<0.001 and p = 0.02, respectively). Rates of OGTT completion at one year (38% vs. 19% p<0.001) were higher in women who attended clinics with postpartum reminders.
The site of diabetes care in pregnancy is a major predictor of adherence to diabetes screening postpartum. Health care delivery should be considered in the development of strategies to increase screening rates.
The epidemiology of infections in the puerperium (post partum period) is not well understood and remains underestimated because surveillance systems are often limited to the acute care setting. The most common source of persistent fever after delivery is genital tract infection for which diagnosis remains mostly clinical and antibiotic treatment empiric. This review will emphasize surgical site infections (SSIs) and endometritis. Septic thrombo-phlebitis, mastitis, urinary tract infections and rare infections will be covered in less detail. Puerperal sepsis will not be reviewed.
To examine the impact of nephrotic range proteinuria during pregnancy on renal, maternal and fetal outcomes.
A retrospective study of pregnant women with proteinuria greater than 3 g/24 h. Outcome measures included: gestation and mode of delivery, maternal high dependency unit admission, birth weight, maternal blood pressure and proteinuria at time of last follow-up, renal biopsy.
Two hundred and sixty four pregnancies in 262 women were reviewed. Postnatal data were available in 180; of these 104 (57%) had urinary protein quantified postnatally. Sixty three (60%) were pure preeclampsia and nine (9%) super-imposed preeclampsia. Biopsy-proven renal disease was newly diagnosed in nine (9%). Sixty three per cent required caesarean section and 34% required high dependency unit admission. There were no maternal deaths. Birth weight corrected for gestation was below the fifth centile in 33%.
The incidence of underlying renal pathology in this cohort is significant and highlights the importance of careful follow-up.
Aortopathies, or disease affecting the aorta, are associated with a significant mortality risk for the mother and foetus during pregnancy because of an increased rate of aortic dissection. The hereditary aortopathies; Marfan’s syndrome, bicuspid aortic valve, Loeys–Dietz syndrome, Ehlers–Danlos (type IV) syndrome, Turner’s syndrome and nonsyndromic familial thoracic aortic aneurysm and dissection are all associated with an increased risk of aortic dissection particularly during the third trimester and early postpartum period. Maternal outcome in pregnancy depends on the underlying disorder and the aortic dimensions prior to pregnancy. The foetus has up to 50% chance of inheriting the underlying genetic defect. Vasculitis, particularly Takayasu’s arteritis may also be a problem in pregnancy and predispose to aortic dissection. Prepregnancy review, including careful assessment of the aorta and prophylactic aortic surgery for an aortic aneurysm may reduce the risk of aortic dissection in pregnancy for some of the aortopathies but for women with Marfan’s syndrome, Loeys–Dietz syndrome and Ehlers–Danlos (vascular type IV) who have had surgery, the risk of death remains high. A subgroup of women with Marfan’s syndrome or a bicuspid aortic valve and normal aortic dimensions prepregnancy should do well in a pregnancy. Multidisciplinary pregnancy care with agreement on pregnancy follow-up, delivery and postpartum care with a crisis plan for an aortic dissection can improve pregnancy outcome and ensure prompt management of an aortic dissection should it occur.
Maternal obesity is a well established risk factor for gestational diabetes but it is not known if the pattern of maternal fat distribution predicts adverse pregnancy outcomes.
Body composition was assessed by bioimpedance using Inbody 720® in 302 consecutive obese pregnant women attending a weight management clinic. The relation of visceral fat mass and total percentage body fat with the development of gestational diabetes and perinatal outcomes was evaluated.
Women developing gestational diabetes (Group 1; n = 72) were older, had higher body mass indices and greater central obesity (waist:hip ratio, visceral fat mass) compared with those remaining normoglycaemic. Visceral fat mass, but not percentage body fat, correlated with fasting glucose in all patients (r = 0.2, p < 0.001) and particularly those in Group 1 (r = 0.35, p = 0.002). Visceral fat mass, but not percentage body fat, also correlated strongly with glycaemia, particularly in Group 1 (r = 0.47, p < 0.0001). Visceral fat mass also showed a weak but significant correlation with baby weight (r = 0.17, p = 0.01).
Central obesity, as assessed by early pregnancy waist:hip ratio and particularly by visceral fat mass, is a predictor of gestational diabetes in addition to classical risk factors and may help identify those obese patients at increased risk of complications.
Depression is common in women of childbearing age. Whereas non-pharmacological interventions are recommended as first line interventions, pharmacological treatment may be required. Selective serotonin reuptake inhibitors (SSRIs) are the most commonly prescribed antidepressants in pregnancy. Ideally, discussion of the risks and benefits of SSRI use in pregnancy should occur prior to pregnancy. The potential risks of psychotropic medications need to be balanced against the risks associated with untreated psychiatric conditions and the discontinuation of necessary medications.
Pulmonary hypertension remains a major cause of cardiac maternal death in the developed world. Over the last two decades, effective therapies for pulmonary hypertension have been developed, improving symptoms and survival. Consequently, increasing numbers of women with pulmonary hypertension and childbearing potential exist, with a number considering pregnancy. Patients with pulmonary hypertension may also present for the first time during pregnancy or shortly following delivery. The last decade has seen increasing reports of women with pulmonary hypertension surviving pregnancy using a variety of approaches but there is still a significant maternal mortality at between 12% and 33%. Current recommendations counsel that patients with known pulmonary hypertension should be strongly advised to avoid pregnancy with the provision of clear contraceptive advice and termination of pregnancy should be considered in its eventuality. In patients who are fully informed and who have been counselled regarding the risks of continuing with pregnancy, there is growing evidence that a multi-professional approach with expert care in pulmonary hypertension centres may improve outlook, although the mortality remains high.
Intravenous fluid given to women with pre-eclampsia may be a necessary form of treatment; however, intravenous fluid therapy can also cause iatrogenic pulmonary oedema. The indications for the use of intravenous fluids, the titration of the amount of fluid given and the use of invasive monitoring have not been subject to adequate examination in randomised studies. Clinical experience, combined with available evidence and a reasoned approach are the basis for a suggested management algorithm.
The relative hypercoagulable state of pregnancy leads to an increased risk of thrombotic complications, of which some may be life-threatening or medically devastating. In the non-pregnant patient, the current guidelines suggest thrombolysis as the primary treatment in acute ischemic stroke, myocardial infarction when percutaneous intervention is unavailable, certain cases of mechanical valve thrombosis, and pulmonary embolism with hemodynamic compromise or shock. Given that clinical trial data regarding thrombolytic use in pregnant women are absent due to exclusion, the goal of this review is to summarize the available published data regarding the use of thrombolytic agents and subsequent outcomes and complications in pregnant women. Overall, the use of thrombolytic agents in pregnancy is associated with a relatively low reported complication rate, especially given the severe medical conditions for which they are indicated. The data would suggest that thrombolysis should be considered for appropriate indications similar to that of non-pregnant patients. However, caution should be exercised when drawing conclusions regarding maternal and fetal safety, given the lack of controlled clinical trials including pregnant women and the nature of the weak evidence level of the cumulative data presented in this review.
A published audit demonstrated that a pilot psychiatric clinic failed to capture predicted numbers of women with severe and enduring mental illness.
On the basis of recommendations from this audit, along with those from the Royal College of Psychiatrists and NICE guidelines, a more comprehensive psychiatric service was developed to meet this demand and therefore manage risk more effectively.
Over the course of a year, the new service attracted a higher rate of referrals of pregnant women with severe and enduring mental illness. The majority referral source continued to be midwifery-led.
Audit is a useful tool for evaluating and informing service development and helped us identify further improvements needed to deliver an effective mental health service.
Historically the rates of postpartum glucose tolerance testing for women with gestational diabetes (GDM) average a suboptimal 33%. Barriers include the need for new mothers to miss work and/or arrange for childcare in order to engage in a two-hour test at a commercial lab. This pilot study was initiated to test the theory that a home testing regimen would be accepted by patients and increase the rate of postpartum glucose assessments relative to published rates, without requiring additional health-care staff or resources to achieve this goal.
Six weeks postpartum, women with GDM from an academic private practice were asked to check fingerstick blood glucose (FAST Protocol) four times a day for two days, and then obtain an oral glucose tolerance test (OGTT). The physician consultants saw the women each month during pregnancy and arranged the postpartum testing.
Two of 69 refused to be consented. Twelve of the remaining 67(18%) women completed both the FAST regimen and the OGTT, three completed only the OGTT and five completed only the FAST regimen for a final follow-up rate of 20/67 (30%). The demands of caring for a newborn, or the annoyance of fingersticks, were barriers to compliance.
In spite of intense physician involvement, this home testing regimen was not associated with an increase in the rates of women participating in postpartum glucose assessments.
To determine the diagnostic effectiveness of the fasting and one-hour plasma glucose levels for gestational diabetes (GDM) based on International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria.
A cross-sectional study that included 2348 pregnant women booked for antenatal care in 2011 at a tertiary care perinatal institute. Pregnant women underwent a 75 g oral glucose tolerance test (OGTT) between 24 and 28 weeks of gestation. Outcome measures include the incidence of GDM based on the IADPSG criteria and the diagnostic effectiveness of the recommended fasting and one-hour plasma glucose cut-off if used in isolation.
The incidence of GDM was 21.81% (n = 520, 95% CI: 20.15, 23.57) with the IADPSG criteria. A fasting plasma glucose cut-off 92 mg/dL, in isolation, correctly classified 87.16% of GDM, with a specificity of 96.08%, clinically significant positive likelihood ratio (14.08) and a post-test probability of 79.71%. The one-hour 75 g test, in isolation, correctly classified 85.74% of GDM, had specificity of 99.68% and clinically significant positive likelihood ratio (111.12) and post-test probability of 96.87%. The application of the World Health Organization criteria would misclassify 11.91% (95% CI: 10.66, 13.26) of GDM as normal.
Additional testing of plasma glucose levels can be avoided for 18.25% (n = 435, 95% CI: 16.73, 19.84) if the IADPSG diagnostic criteria for GDM are applied with exit on a positive fasting or one-hour test result.