Antiretroviral therapy in pregnancy: a focus on safety

People living with HIV and procreation: 30 years of progress from prohibition to freedom?

The emergence of human immunodeficiency virus (HIV) infection in the 1980s drastically changed the prospects of conceiving a child for the man or woman infected with the virus. Advances in treatment then made it possible to envisage pregnancy while decreasing the risk of transmission to the child when the mother was infected. For couples where one partner was HIV-positive and who desired a child, recourse to medical help, notably medically assisted procreation, was discouraged, and very few centres offered such assistance in the 1980s and 1990s. Improved knowledge of viral excretion in the genital tracts, together with more effective treatment, made it possible to envisage medically assisted procreation for these couples, allowing them to have a child while at the same time likely reducing the risk of transmitting HIV to their partner. Several programmes have demonstrated their effectiveness in this domain. Owing to continually increasing knowledge over the past decade, natural conception can now be proposed. Couples where one or both partners are HIV-positive may opt for medically assisted procreation or natural reproduction. Specialists in reproductive medicine and HIV specialists need to provide couples with objective information allowing them to achieve near-optimal conditions that minimize HIV transmission risk. Couples will then be able to choose freely the mode of procreation most appropriate for them.

Birth defects in a cohort of infants born to HIV-infected women in Spain, 2000-2009

BACKGROUND

Antiretroviral therapy (ART) in pregnancy has resulted in a marked impact on reducing the risk of mother-to-child transmission (MCT) of HIV. However the safety of in utero ART exposure in newborns remains a concern.

METHODS

A multicenter prospective observational study of HIV-infected mother and their infants was performed in Madrid, Spain, from 2000 to 2009. Children had regular visits with clinical examination according to protocol until the age of 24 months. An abdominal ultrasound and an echocardiogram were scheduled during follow up. Birth defects (BDs) were registered according to European Surveillance of Congenital Anomalies (EUROCAT).

RESULTS

A total of 897 live births from 872 mothers were included. Overall the birth defects prevalence observed was 6.9% (95% CI 5.4-9.1).The most commonly reported birth defects types were in genital organs and urinary system (19 cases, 30.6%) and cardiovascular system (17 cases, 27.4%). There was no increased risk for infants exposed in the first trimester to ARVs compared with unexposed infants. No significant associations were observed between exposure to any individual antiretroviral agent during pregnancy and birth defects

CONCLUSION

A higher prevalence of BDs was observed, higher than previously reported. In utero exposure to ART was not proved to be a major risk factor of birth defects in infants. However the relatively small number of patients is a major limitation of this study.

Comparison of auditory brainstem response in HIV-1 exposed and unexposed newborns and correlation with the maternal viral load and CD4+ cell counts

OBJECTIVE

The effects of maternal HIV infection and antiretroviral therapy on hearing of HIV-exposed newborns in sub-Saharan Africa have not been investigated. We determined the prevalence of sensorineural hearing loss among HIV-exposed newborns and the association between the hearing threshold and maternal and newborn parameters.

DESIGN

A cohort audiometric study of newborns between October 2012 and April 2013.

SETTINGS

A secondary and tertiary hospital-based study.

PARTICIPANTS

Consecutive 126 HIV-exposed and 121 HIV-unexposed newborns.

INTERVENTION

Hearing screening of the newborns was done with Auditory Brainstem Response and compared with maternal HAART, CD4 cell counts, RNA viral loads and newborn CD4 cell count percentage.

MAIN OUTCOME MEASURE

Hearing threshold levels of both groups were measured and analysed.

RESULTS

Around 11.1% of HIV-exposed and 6.6% of unexposed newborns had hearing impairment (P = 0.2214). About 6.4% of HIV-exposed and 2.5% HIV-unexposed newborns had hearing threshold of more than 20 dBHL (P = 0.1578). There was no significant association between the hearing thresholds of HIV-exposed newborns and maternal CD4 cell counts (P = 0.059) but there was with maternal viral load (P = 0.034). There was significant difference between the hearing thresholds of HIV-exposed newborns with CD4% of 25 or less and more than 25. This study showed significant difference in the hearing of the 119 HAART-exposed newborns and seven unexposed newborns [P = 0.002; risk ratio, 0.13 (0.05-0.32)].

CONCLUSION

There was a trend towards more hearing loss in HIV-exposed newborns. However, hearing thresholds increase with increasing mothers' viral load. The background information supports the need for further studies on the role of in-utero exposure to HIV and HAART in newborn hearing loss.

Antiretroviral Prophylaxis and the Risk of Cleft Lip and Palate: Preliminary Signal Detection in the Food and Drug Administration's Adverse Events Reporting System Database

Objective

Antiretroviral prophylaxis has been found to be effective in preventing vertical HIV transmission to the offspring of infected mothers. Because medicine and the art of public health require benefits to outweigh any plausible risks, our study aimed to explore and quantify preliminary associations between antiretroviral medications and clefting.

Methods

We analyzed 5 years of available data from the Food and Drug Administration's Adverse Events Reporting System (Medwatch program) and calculated reporting odds ratios (RORs) and their associated 95% confidence intervals (CIs).

Results

The medications with the highest effects were efavirenz with an ROR of 196 (95% CI, 86 to 447), lamivudine with an ROR of 60.2 (95% CI, 14.25 to 148), the combination abacavir sulfate/lamivudine/zidovudine with an ROR of 59.3, and nelfinavir with and ROR of 50.5, followed by nevirapine, lopinavir/ritonavir, and lamivudine/zidovudine.

Conclusion

Given the multifactorial etiology of cleft lip and palate, further studies are needed to assess the relative safety of antiretroviral prophylaxis and the specific conditions or potential synergies that might lead to the development of this defect.

[In-utero antiretroviral exposure and mitochondrial toxicity in a cohort of uninfected infants born to HIV-1-infected women]

INTRODUCTION

In this study, we attempt to find out the percentage of uninfected infants born to HIV-infected women and exposed in-utero and perinatally to Antiretroviral Treatment (ART) that show high lactate levels, or any other mitochondrial damage markers (such as hypertransaminasaemia or hyperamylasaemia), during the first three months of age. We shall also establish whether certain drugs used in-utero are associated with higher lactate, transaminase or amylase levels.

METHODS

We analysed the available data from 623 uninfected infants born in the Spanish FIPSE cohort that were born in the period 2000-2005. The normal values for lactate, transaminases and amylase were set according to AIDS Clinical Groups Trials toxicity tables for infants.

RESULTS

The percentages of children with high lactate levels at 0.5; 1.5 and 3 months of age were 48%, 51.4% and 43% among those infants with available data. Respectively, the percentages of children with high AST values were 13.2; 10.4 and 17.2%. The values for high ALT were 3.3%; 3.4% and 5%. The percentages for hyperamylasaemia were 0%; 0.6% and 2.6%. We found no significant difference among the drugs used in utero for the four analysed biochemical markers along the first three months of age.

CONCLUSIONS

We have found a high proportion of hyperlactataemia among infants exposed in-utero to ART, as shown in other cohorts of similar characteristics. No morbidity or mortality was communicated to the cohort analysis group. No ART drug among those used in-utero was statistically associated with a higher proportion of high lactate levels in these infants.

Advances and failures in preventing perinatal human immunodeficiency virus infection

An estimated 2.5 million children are currently living with HIV, the vast majority as a result of mother-to-child transmission. Prevention of perinatal HIV infection has been immensely successful in developed countries. A comprehensive package of services, including maternal and infant antiretroviral therapy, elective cesarean section, and avoidance of breast-feeding, has resulted in transmission rates of less than 2%. However, in developing countries, access to such services is often not available, as demonstrated by the fact that the vast majority of children with HIV live in Africa. Over the past few years, many developing nations have made great strides in improving access to much-needed services. Notably, in eastern and southern Africa, the regions most affected by HIV, mother-to-child-transmission coverage rates for HIV-positive women increased from 11% in 2004 to 31% in 2006. These successes are deserving of recognition, while not losing sight of the fact that much remains to be done; currently, an estimated 75% of pregnant women worldwide have an unmet need for antiretroviral therapy. Further work is needed to determine the optimal strategy for reducing perinatal transmission among women in resource-poor settings, with a particular need for reduction of transmission via breast-feeding.

[Birth defects in a cohort of uninfected children born to HIV-infected women]

INTRODUCTION

Mother-to-Child HIV transmission is now just 1% in western countries, due to prevention measures. Antiretroviral Treatment (ART) drugs do have adverse effects, anaemia and myelosupression caused by cidovudina being the most commonly observed effects. In the present study, we have analysed the proportion and characteristics of congenital malformations (CM) or birth defects (BD) in a cohort of uninfected children born to HIV-infected women.

METHODS

A total of 623 uninfected children belonging to the FIPSE cohort were followed up according to standardised protocols. This cohort includes 8 public hospitals from Madrid and follows up HIV-infected pregnant women and their children. Children were classified according to prematurity, ethnic origin, birth weight, withdrawal syndrome, in-utero treatment. Birth defects were described and defined according to the EUROCAT, the European registry for BD. Mild errors of morphogenesis were excluded from the analysis. Categorical variables were compared with the X(2) or the Fisher test.

RESULTS

A total of 78% (486) of the mothers were of Caucasian origin; 18.8% (117) used some illicit drug (heroine, cocaine or methadone) during gestation; 51 mothers (8.1%) received no ART, 10 (1.6%) received monotherapy and 469 (75.3%) received HAART. BD were seen in 52 children, with the most frequent being genitourinary and cardiological. Anaemia in the first trimester was an associated risk for BD (17.9% vs. 8.1%, P = 0,04). Similarly, mothers who used any illicit drug (plus methadone), had a slightly higher risk for BD in their offspring (13.8% vs. 7.6%, P = 0,04) There was no increased risk for BD significantly associated with any of the in-utero used antiretrovirals, although Nevirapine use in-utero showed a protective effect. Children born to mothers who received ART in the first trimester had the same rate of BD (7.4%) as those whose mothers started ART in the second trimester (8.8%), P = 0,67.

CONCLUSIONS

The proportion of BD that we have observed seems higher than those shown in other European teratogenicity studies and also higher than those shown in cohorts with HIV and antiretroviral exposed infants. This may be due to the fact that our series show the results of an active surveillance system (that includes ultrasound), where BD classically appear in a higher proportion. Immunovirological characteristics of the mother did not influence the proportion of BD, but anaemia in the fist trimester and the use of illicit drugs (or methadone) did. No specific antiretroviral drug was associated with an increase in BD, although Nevirapine showed a possible protective effect in the statistical analysis. Mothers who started antiretrovirals in the first trimester do not have more BD in their offspring than mothers who started on antiretrovirals later on.

Haemoglobin and albumin as markers of HIV disease progression in the highly active antiretrovial therapy era: relationships with gender

OBJECTIVES

The aims of the study were to describe gender differences in haemoglobin and albumin and to investigate the prognostic value of these measurements in relation to highly active antiretroviral therapy (HAART).

METHODS

Anaemia was defined as haemoglobin <13.5 g/dL for men and <11.5 g/dL for women. Albumin <35 g/L was defined as hypoalbuminaemia. Proportional hazards models were used to describe relationships between these markers and HIV progression and death.

RESULTS

A total of 291 patients had pre-HAART and 1-year measurements. Mean haemoglobin and albumin levels pre-HAART were lower in women than in men (haemoglobin: 11.2 vs 13.2 g/dL, respectively, P<0.0001; albumin: 37.4 vs 40.2 g/L, respectively, P<0.0001), and a higher proportion of women were anaemic and hypoalbuminaemic compared with men. Despite a rise in both markers in the first year on HAART, mean haemoglobin levels remained lower by 2.08 g/dL (P<0.0001) and albumin by 2.88 g/L (P<0.0001) in women. In the 495 patients included in this analysis, haemoglobin and albumin levels were both significantly related to short-term risk of AIDS and death independently of CD4 count [hazards ratio (HR)=0.73/g/dL higher haemoglobin, 95% confidence interval (CI) 0.55-0.82, P<0.0001 and HR=0.87/g/L higher albumin, 95% CI 0.83-0.91, P<0.0001]. The prognostic value did not differ by gender.

CONCLUSIONS

Women were more likely to be anaemic and/or hypoalbuminaemic pre-HAART, but post-HAART increases were similar to those in men. Both haemoglobin and albumin were strong independent prognostic factors for risk of AIDS and death, regardless of gender.

Antiretroviral Therapy and Congenital Abnormalities in Infants Born to HIV-1-Infected Women in the United Kingdom and Ireland, 1990 to 2003

Antiretroviral therapy (ART) in pregnancy substantially reduces the risk of mother-to-child transmission of HIV, but concerns exist about the potential for teratogenic effects. This analysis was undertaken to explore the relation between ART in pregnancy and birth defects in infants born to HIV-infected women in the United Kingdom and Ireland between 1990 and 2003. Comprehensive obstetric and pediatric HIV surveillance is carried out through the National Study of HIV in Pregnancy and Childhood. Congenital abnormalities were reported in 101 of 3172 infants (100 of 3120 pregnancies). There was no statistically significant association between the prevalence of congenital abnormalities and exposure to ART overall: 3.4% (90 of 2657 pregnancies) in exposed pregnancies and 2.2% (10 of 463 pregnancies) in nonexposed pregnancies (P = 0.166); prevalence was similar whether or not exposure occurred in the first trimester: 3.7% (20 of 541 pregnancies) after early exposure and 3.1% (80 of 2579 pregnancies) without early exposure (P = 0.476). There was also no significant association with type of ART in early pregnancy (ie, highly active antiretroviral therapy [HAART] vs. mono- or dual therapy, HAART with protease inhibitor and/or nonnucleoside reverse transcriptase inhibitor). The lack of association was maintained after adjustment for potential confounding factors. These findings are reassuring, but continued monitoring is essential in view of the increasing number of women on therapy at conception and the likely continuing diversity of drug regimens.

Human Immunodeficiency Virus: Anesthetic and Obstetric Considerations

The pandemic of acquired immune deficiency syndrome (AIDS) is on the threshold of its third decade of existence. The World Health Organization-United Nations statistics show that human immunodeficiency virus (HIV)/AIDS pandemia is set to get much worse. Women of reproductive age are the fastest growing population with HIV. Common signs and symptoms have become more moderate or subclinical, and new clinical presentations have emerged. It is quite apparent that HIV-disease affects multiple organ systems. Advances have been made in elucidating the pathogenesis of HIV. In addition, the molecular technique of viral load determination and the CD + 4 T-lymphocyte count enable evaluation of the disease, its prognosis, and its response to therapy. There is limited specific information concerning the overall risk of anesthesia and surgery of HIV/AIDS patients. However, as far as can be determined, surgical interventions do not increase the postoperative risk for complications or death and should therefore not be withheld. There is also little evidence to suggest that HIV or antiretroviral drugs increase the rate of pregnancy complications or that pregnancy may alter the course of HIV infection. General anesthesia is considered safe, but drug interactions and their impact on various organ systems should be considered preoperatively. Regional anesthesia is often the technique of choice. Yet, one must take into consideration the presence of neuropathies, local infection, or blood clotting abnormalities. It should be emphasized that all practicing anesthesiologists should be familiar with the disease and should use prenatal anesthesia consultations and a team approach to assure optimal treatment for HIV patients.

A pilot study to evaluate the safety and feasibility of the administration of AZT/3TC fixed dose combination to HIV infected pregnant women and their infants in Rio de Janeiro, Brazil

OBJECTIVES

To evaluate the safety and feasibility of zidovudine and lamivudine (AZT/3TC) given to HIV infected pregnant women and their infants in Rio de Janeiro, Brazil.

METHODS

This open label phase II study enrolled 40 HIV infected antiretroviral naive women >or=20 weeks gestation, CD4 <500 cells x10(6)/l, from two public hospitals.

TREATMENT

fixed dose AZT 300 mg/3TC 150 mg by mouth every 12 hours until labour; AZT 300 mg by mouth every 3 hours until delivery; infants: AZT 4 mg/kg every 12 hours plus 3TC 2 mg/kg every 12 hours for 6 weeks. Blood haematology and chemistry were monitored; adherence evaluated by pills count; efficacy measured by changes in lymphocyte (CD4) and viral load, and by HIV RNA-PCR tests performed at birth, 6 and 12 weeks, to diagnose infant infection. No women breast fed.

RESULTS

PATIENT CHARACTERISTICS

mean age 24.48 (SD 3.5) years; gestational age 24.5 (4.5) weeks; AZT/3TC duration 14.4 (4.4) weeks; vaginal delivery: 11/39; caesarean section: 28/39. Entry and pre-labour CD4: 310/486 cells x10(6)/l (p<0.001); entry and pre-labour viral load: 53 818/2616 copies/ml (p<0.001). Thirty nine women tolerated treatment with >80% adherence; one was lost to follow up. Five newborns were excluded from 3TC receipt. All 39 babies were uninfected. Haematological toxicity in newborns was common: anaemia in 27; neutropenia in five (two severe); platelets counts <100000 in two. All values recovered on study completion.

CONCLUSIONS

Fixed dose AZT/3TC is well accepted, gives improvements in CD4 and viral load; no infants were HIV infected. Haematological toxicity in infants needs careful monitoring.

Mitochondrial toxicity in fetal Erythrocebus patas monkeys exposed transplacentally to zidovudine plus lamivudine

This study was designed to investigate fetal mitochondrial toxicity in Erythrocebus patas monkeys exposed in utero to zidovudine (AZT) and lamivudine (3TC), and taken at term. Pregnant patas monkeys were given a daily dose of 40 mg AZT (86% of the human daily dose, based on body weight), for the last 10 weeks (50%) of gestation, and a daily dose of 24 mg 3TC (84% of the human daily dose, based on body weight) for the last 4 weeks of gestation. At term, AZT was found to be incorporated into fetal mitochondrial DNA from skeletal muscle, liver, kidney, and placenta. By transmission electron microscopy (EM) drug-exposed fetal cardiac and skeletal muscle cells showed mitochondrial membrane compromise, mitochondrial proliferation, and damaged sarcomeres, while mitochondria in brain cerebrum and cerebellum were morphologically normal. Substantial depletion of oxidative phosphorylation (OXPHOS) Complex I specific activities was observed in heart (87% reduction in mean, p = 0.02) and skeletal muscle (98% reduction in mean, p = 0.002) from drug-exposed fetuses, compared to unexposed fetuses. In addition Complex IV activity was highly depleted (85% reduction in mean, p = 0.004) in skeletal muscle from the drug-exposed fetuses (p = 0.004). Brain cerebrum and cerebellum showed no statistically significant OXPHOS changes with drug exposure. Mitochondrial DNA quantity was substantially depleted (>50%) in heart, skeletal muscle, cerebellum, and cerebrum from drug-exposed fetuses compared to unexposed controls. Overall, the data indicate that significant mitochondrial damage was observed at birth in monkey fetuses exposed in utero to AZT plus 3TC in a human-equivalent dosing protocol.

Perinatal antiretroviral treatment and hematopoiesis in HIV-uninfected infants

BACKGROUND

The perinatal prophylactic administration of zidovudine is associated with rapidly reversible macrocytic anemia in infants. However, a recent study suggests that there may be more persistent inhibition of hematopoïetic stem cells.

OBJECTIVE

To study hematopoiesis in uninfected infants, born to HIV-1 seropositive mothers, including those exposed and those not exposed to perinatal zidovudine alone or in combination.

METHODS

Longitudinal study, from 0 to 18 months, of hemoglobin, platelets, polynuclear neutrophils, total lymphocytes, and CD4+ and CD8+ lymphocytes in more than 4000 infants of the French Perinatal Study. Modeling of repeated measures and non-linear evolution with age, with models combining natural cubic B-splines and random effects.

RESULTS

The hemoglobin level was transiently reduced in newborns exposed to zidovudine. Multivariate analysis taking into account age, prematurity, geographical origin, maternal drug use and maternal CD4 cell count, indicated that levels of the three other lineages were slightly lower until age 18 months in exposed than not exposed infants (P < 0.0001 for each lineage). There was a negative relationship between the duration of exposure and each hematological variable. Combinations of antiretroviral treatments were associated with larger decreases than monotherapy up to 15 months of age. Similar, but less pronounced, patterns were found for the CD4+ and CD8+ subpopulations of lymphocytes.

CONCLUSIONS

Zidovudine administered during the perinatal period may result in a small but significant and durable effect on hematopoïesis up to the age of 18 months.

Persistent mitochondrial dysfunction in HIV-1-exposed but uninfected infants: clinical screening in a large prospective cohort

BACKGROUND

Antiretroviral prevention of mother to child HIV-1 is established but tolerance remains to be assessed. AIM To determine the risk for persistent mitochondrial dysfunction in HIV-uninfected children born to seropositive mothers.

METHOD

An exhaustive study in a large prospective cohort with predetermined algorithm of the unexplained symptoms compatible with mitochondrial dysfunction. A total of 2644 of 4392 children were exposed to antiretrovirals. Complementary investigations were carried out on a case-by-case basis using classification with a diagnostic probability scale, based on experience with constitutional diseases. A spontaneous notification register for children not included in the cohort was created.

RESULTS

Good circumstantial evidence of mitochondrial dysfunction was found for twelve children. Seven were from the cohort. All presented neurological symptoms, often associated with abnormal magnetic resonance image (10 of 12) and/or a significant episode of hyperlactatemia (seven of 12). All had either a profound deficit in one of the respiratory chain complexes (11 of 12) and/or a typical histological pattern (two of 12). All were perinatally exposed to antiretrovirals. None of them had perinatal morbidity that could explain this symptomatology. The 18-month incidence was 0.26% (95% confidence interval, 0.10-0.54) in exposed children, in comparison with the general figure of 0.01% for paediatric neuro-mitochondrial diseases in the general population. Fourteen other children in the cohort, all exposed to antiretrovirals, had unexplained symptoms, mostly neurological, for which one of the possible differential diagnoses was mitochondrial dysfunction. Close similarities in clinical, neuroradiological and histological findings strongly suggest a common pathological process in all these 26 children.

CONCLUSION

Children exposed to nucleoside analogues during the perinatal period are at risk of a neurological syndrome associated with persistent mitochondrial dysfunction.

Safety and efficacy of saquinavir soft-gelatin capsules + zidovudine + optional lamivudine in pregnancy and prevention of vertical HIV transmission

BACKGROUND

The treatment of HIV infection during pregnancy significantly and substantially reduces the risk of mother-to-child transmission. Although triple therapy is the standard of care for management of HIV infection in adults, the safety of many approved antiretroviral agents in pregnancy is not currently established.

METHODOLOGY

An open-label pilot study conducted in Thailand and the UK of the safety of saquinavir soft-gel capsules 1200 mg three times daily administered in the second and third trimester of pregnancy in combination with local standard-of-care antiretroviral therapy. Infants received local standard-of-care antiretroviral therapy after delivery. Steady-state pharmacokinetics were performed in a subset of mothers at 4 weeks after the commencement of saquinavir therapy and paired samples collected from the mother and infant cord blood at delivery.

RESULTS

Eighteen antiretroviral-naive pregnant women with a mean viral load of 4.2 log10 and CD4 cell count of 481/mm(3) were recruited. All patients received zidovudine and 3 (all in the UK) received lamivudine. There were no serious adverse events and no discontinuations due to adverse events. Viral load declined by 1.6 log10 at week 4 and was less than 400 copies/mL at delivery in 16/17 mothers. Sixteen live births were recorded, with two in utero deaths-one secondary to an accident and the second due to antiphospholipid syndrome. Both deaths were considered by investigators to be unrelated to study therapy. All infants were HIV negative at subsequent follow-up and no fetal abnormalities were observed. Pharmacokinetic data suggested that mothers had relatively low exposures to saquinavir despite an excellent virologic response. Saquinavir was not detected in cord blood.

DISCUSSION

Saquinavir soft-gel capsules are well tolerated during pregnancy and are not associated in this small study with birth abnormalities. Transmission of HIV infection from mother to child was successfully prevented in all cases. Low maternal exposures of saquinavir were noted. However, these did not appear to affect virologic efficacy of the combination. Samples from cord blood indicate minimal fetal exposure to saquinavir.

Guidelines for the management of HIV infection in pregnant women and the prevention of mother-to-child transmission

AIMS OF THE GUIDELINES: These guidelines, drawn up by a multidisciplinary group of clinicians and lay workers active in the management of pregnant women infected with HIV, aim to give up-to-date information on interventions to reduce the risk of mother to child transmission of the virus. The evidence on the use of interventions to prevent mother to child transmission of HIV has been graded according to the strength of the data as per the definitions of the US Agency for Health Care Policy and Research [1]. Weighted evidence on the use of combination antiretroviral therapy (ART) for the treatment of HIV infection per se is presented in the BHIVA guidelines for adults [2,3]. The highest level evidence (i.e. randomised controlled trials (RCTs) or large, well conducted meta-analyses) is only available for formula feeding, prelabour caesarean section and zidovudine monotherapy. The need to treat mothers for HIV infection has led to the widespread use of ART in pregnancy which in turn results in new questions such as how to deliver when the mother, on therapy, has no detectable plasma viraemia with the most sensitive assays. In addressing many common and/or difficult clinical scenarios in the absence of 'best evidence' the guidelines rely heavily on 'expert opinion'. Recommendations for management are given in the section on clinical scenarios, and summarized in Table 3. An expanded version of these guidelines with an appendix on safety and toxicity data is available on the BHIVA website http://www.bhiva.org. The authors are available to discuss individual cases.