Association between HIV antiretroviral therapy and preterm birth based on antenatal ultrasound gestational age determination: a comparative analysis

Adverse birth outcome research case definitions associated with maternal HIV and antiretroviral drug use in pregnancy: a scoping review

BACKGROUND

Adverse birth outcomes (preterm birth, low birth weight, small for gestational age, and stillbirth) seem to persist in infants born to people with HIV, even in the context of maternal antiretroviral therapy. However, findings have been disparate, inconclusive, and difficult to compare directly across settings, partly owing to variable outcome definitions. We aimed to collate, compare, and map existing adverse birth outcome definitions to inform a harmonized approach to universally measure these outcomes in studies including pregnant people with HIV.

METHODS

We conducted a scoping review of studies that reported adverse birth outcomes associated with maternal HIV and antiretroviral use in pregnancy, specifically those that included definitions of 'preterm birth', 'low birth weight', 'small for gestational age', and 'stillbirth'. Five databases were searched from 01 January 2011 to 15 August 2022. Title, abstract and full-text screening was conducted independently in duplicate. A comparative quantitative analysis was conducted to compare study characteristics by period of study (< 2013; 2013-2015; > 2016) and country income group. A qualitative content analysis was conducted to compare and map deviations from the WHO definitions as a reference.

RESULTS

Of the 294 articles that included at least one adverse birth outcome, 214 (73%) studies started before 2013, 268 (91%) were published as primary research articles, and 137 (47%) were conducted in Eastern and Southern Africa. Among the 283 studies included in the country income group analysis, 178 (63%) were conducted in low- and middle-income countries. Studies reporting low birth weight, preterm birth, small for gestational age and stillbirth deviated from the WHO definitions in n = 11/169 (7%), n = 93/246 (39%), n = 40/112 (36%) and n = 85/108 (79%) instances, respectively. The variations included the use of different thresholds and the addition of new terminology.

CONCLUSION

The current WHO definitions are valuable tools for population-level monitoring; however, through consensus, these definitions need to be optimized for research data collection, analysis, and presentation. In conjunction with good reporting, variation in adverse birth outcome definitions can be decreased to facilitate comparability of studies as well as pooling of data for enhanced evidence synthesis.

Effects of preterm birth, maternal ART and breastfeeding on 24-month infant HIV-free survival in a randomized trial

BACKGROUND

IMPAACT 1077BF/FF (PROMISE) compared the safety/efficacy of two HIV antiretroviral therapy (ART) regimens to zidovudine (ZDV) alone during pregnancy for HIV prevention. PROMISE found an increased risk of preterm delivery (<37 weeks) with antepartum triple ART (TDF/FTC/LPV+r or ZDV/3TC/LPV+r) compared with ZDV alone. We assessed the impact of preterm birth, breastfeeding, and antepartum ART regimen on 24-month infant survival.

METHODS

We compared HIV-free and overall survival at 24 months for liveborn infants by gestational age, time-varying breastfeeding status, and antepartum ART arm at 14 sites in Africa and India. Kaplan-Meier survival probabilities and Cox proportional hazards ratios were estimated.

RESULTS

Three thousand four hundred and eighty-two live-born infants [568 (16.3%) preterm and 2914 (83.7%) term] were included. Preterm birth was significantly associated with lower HIV-free survival [0.85; 95% confidence interval (CI) 0.82-0.88] and lower overall survival (0.89; 95% CI 0.86-0.91) versus term birth (0.96; 95% CI 0.95-0.96). Very preterm birth (<34 weeks) was associated with low HIV-free survival (0.65; 95% CI 0.54-0.73) and low overall survival (0.66; 95% CI 0.56-0.74). Risk of HIV infection or death at 24 months was higher with TDF-ART than ZDV-ART (adjusted hazard ratio 2.37; 95% CI 1.21-4.64). Breastfeeding initiated near birth decreased risk of infection or death at 24 months (adjusted hazard ratio 0.05; 95% CI 0.03-0.08) compared with not breastfeeding.

CONCLUSION

Preterm birth and antepartum TDF-ART were associated with lower 24-month HIV-free survival compared with term birth and ZDV-ART. Any breastfeeding strongly promoted HIV-free survival, especially if initiated close to birth. Reducing preterm birth and promoting infant feeding with breastmilk among HIV/antiretroviral drug-exposed infants remain global health priorities.

Metabolomic profiling of preterm birth in pregnant women living with HIV

BACKGROUND

Preterm birth is a leading cause of death in children under the age of five. The risk of preterm birth is increased by maternal HIV infection as well as by certain antiretroviral regimens, leading to a disproportionate burden on low- and medium-income settings where HIV is most prevalent. Despite decades of research, the mechanisms underlying spontaneous preterm birth, particularly in resource limited areas with high HIV infection rates, are still poorly understood and accurate prediction and therapeutic intervention remain elusive.

OBJECTIVES

Metabolomics was utilized to identify profiles of preterm birth among pregnant women living with HIV on two different antiretroviral therapy (ART) regimens.

METHODS

This pilot study comprised 100 mother-infant dyads prior to antiretroviral initiation, on zidovudine monotherapy or on protease inhibitor-based antiretroviral therapy. Pregnancies that resulted in preterm births were matched 1:1 with controls by gestational age at time of sample collection. Maternal plasma and blood spots at 23-35 weeks gestation and infant dried blood spots at birth, were assayed using an untargeted metabolomics method. Linear regression and random forests classification models were used to identify shared and treatment-specific markers of preterm birth.

RESULTS

Classification models for preterm birth achieved accuracies of 95.5%, 95.7%, and 80.7% in the untreated, zidovudine monotherapy, and protease inhibitor-based treatment groups, respectively. Urate, methionine sulfone, cortisone, and 17α-hydroxypregnanolone glucuronide were identified as shared markers of preterm birth. Other compounds including hippurate and N-acetyl-1-methylhistidine were found to be significantly altered in a treatment-specific context.

CONCLUSION

This study identified previously known as well as novel metabolomic features of preterm birth in pregnant women living with HIV. Validation of these models in a larger, independent cohort is necessary to ascertain whether they can be utilized to predict preterm birth during a stage of gestation that allows for therapeutic intervention or more effective resource allocation.

Bone and Renal Health in Infants With or Without Breastmilk Exposure to Tenofovir-Based Maternal Antiretroviral Treatment in the PROMISE Randomized Trial

BACKGROUND

We assessed bone and kidney outcomes in infants randomized postdelivery as mother-infant pairs within the IMPAACT PROMISE trial to maternal tenofovir disoproxil fumarate-based antiretroviral treatment (mART) or infant nevirapine prophylaxis (iNVP) to prevent breastfeeding HIV transmission.

METHODS

Infants were coenrolled in the P1084s substudy on randomization day and followed through Week 74. Lumbar spine bone mineral content (LS-BMC) was assessed at entry (6-21 age days) and Week 26 by dual-energy x-ray absorptiometry. Creatinine clearance (CrCl) was calculated at entry; Weeks 10, 26, and 74. Student t tests compared mean LS-BMC and CrCl at Week 26 and mean change from entry between arms.

RESULTS

Of 400 enrolled infants, the mean (SD; n) for entry LS-BMC was 1.68 g (0.35; n = 363) and CrCl was 64.2 mL/min/1.73 m 2 (24.6; n = 357). At Week 26, 98% of infants were breastfeeding and 96% on their assigned HIV prevention strategy. The mean (SD) Week 26 LS-BMC was 2.64 g (0.48) for mART and 2.77 g (0.44) for iNVP; mean difference (95% confidence interval [CI]) -0.13 g (-0.22 to -0.04), P = 0.007, n = 375/398 (94%). Mean absolute (-0.14 g [-0.23 to -0.06]) and percent (-10.88% [-18.53 to -3.23]) increase in LS-BMC from entry was smaller for mART than iNVP. At Week 26, the mean (SD) CrCl was 130.0 mL/min/1.73 m 2 (34.9) for mART vs. 126.1 mL/min/1.73 m 2 (30.0) for iNVP; mean difference (95% CI) 3.8 (-3.0 to 10.7), P = 0.27, n = 349/398 (88%).

CONCLUSION

Week 26 mean LS-BMC was lower in infants in the mART group compared with the iNVP group. However, this difference (∼0.23 g) was less than one-half SD, considered potentially clinically relevant. No infant renal safety concerns were observed.

Understanding clinical outcome measures reported in HIV pregnancy studies involving antiretroviral-naive and antiretroviral-experienced women

HIV infection is a clinically significant public health disease and contributes to increased risk of maternal and fetal morbidity and mortality. HIV pregnancy studies use outcome measures as metrics to show how people with HIV feel, function, or survive. These endpoints are crucial for tracking the evolution of HIV illness over time, assessing the effectiveness of antiretroviral therapy (ART), and comparing outcomes across studies. Although the need for ideal outcome measures is widely acknowledged, selecting acceptable outcome measures for these HIV pregnancy studies can be challenging. We discuss the many outcome measures that have been implemented over time to assess HIV in pregnancy studies, their benefits, and drawbacks. Finally, we offer suggestions for improving the reporting of outcome measures in HIV in pregnancy studies. Medical professionals can best care for pregnant women living with HIV receiving ART by having a thorough understanding of these outcome metrics.

Progesterone and prolactin levels in pregnant women living with HIV who delivered preterm and low birthweight infants: A nested case-control study

BACKGROUND

Antiretroviral therapy (ART) is associated with high rates of adverse birth outcomes, including preterm birth and low birthweight. Studies suggest that progesterone and prolactin may play important intermediary roles.

METHODS

We analyzed data from the Antenatal Component of the PROMISE trial, a multi-center study of pregnant women taking antiretroviral regimens (lopinavir/ritonavir-containing ART or zidovudine alone) to prevent mother-to-child HIV transmission. In a nested case-control study, we compared data from women who gave birth to preterm (<37 weeks gestation) and/or low birthweight (<2500 g) infants to matched individuals who did not. We measured serum progesterone and prolactin at 24-34 weeks gestation. We used conditional logistic regression to describe relationships between hormone levels, birth outcomes, and antiretroviral regimens.

RESULTS

299 women and their newborns were included (146 cases, 153 controls). When compared to women receiving zidovudine alone, those on ART had higher odds of progesterone levels under the 10th percentile (adjusted odds ratio [AOR]:2.34, 95%CI:1.41-3.89) and 25th percentile (AOR:2.07, 95%CI:1.46-2.94). However, higher levels of progesterone-rather than lower levels-were associated with our composite case outcome at the 10th percentile (AOR:1.88, 95%CI:0.77-4.59) and 25th percentile (AOR:1.96, 95%CI:1.06-3.61). Associations were not observed between prolactin, antiretroviral regimen, and birth outcomes.

CONCLUSION

We observed lower progesterone levels among women allocated to ART regimens; however, higher progesterone levels were associated with preterm birth and/or low birthweight. While features of the study design may have contributed to these findings, they nevertheless highlight the potentially complex mechanisms underpinning adverse birth outcomes and HIV.

Surveillance of ARV safety in pregnancy and breastfeeding: towards a new framework

INTRODUCTION

As new antiretrovirals (ARVs), including long-acting ARVs for treatment and prevention, are approved and introduced, surveillance during pregnancy must become the safety net for evaluating birth outcomes, especially those that are rare and require large numbers of observations. Historically, drug pharmacovigilance in pregnancy has been limited and fragmented between different data sources, resulting in inadequate data to assess risk. The International Maternal Pediatric Adolescent AIDS Clinical Trials Network and World Health Organization convened a Workshop which reviewed strengths and weaknesses of existing programs and discussed an improved framework to integrate existing safety data sources and promote harmonization and digitalization.

DISCUSSION

This paper highlights that although robust sources of safety data and surveillance programs exist, key challenges remain, including unknown denominators, reporting bias, under-reporting (e.g. in voluntary registries), few data sources from resource-limited settings (most are in North America and Europe), incomplete or inaccurate data (e.g. within routine medical records). However, recent experiences (e.g. with safety signals) and current innovations (e.g. electronic record use in resource-limited settings and defining adverse outcomes) provide momentum and building blocks for a new framework for active surveillance of ARV safety in pregnancy. A public health approach should be taken using data from existing sources, including registries of pregnancy ARV exposure and birth defects; observational surveillance and cohort studies; clinical trials; and real-world databases. Key facilitators are harmonization and standardization of outcomes, sharing of materials and tools, and data linkages between programs. Other key facilitators include the development of guidance to estimate sample size and duration of surveillance, ensuring strategic geographic diversity, bringing partners together to share information and engaging the community of women living with HIV.

CONCLUSIONS

Looking ahead, critical steps to safely introduce new ARVs include (1) adopting harmonized standards for measuring adverse maternal, birth and infant outcomes; (2) establishing surveillance centres of excellence in areas with high HIV prevalence with harmonized data collection and optimized electronic health records linking maternal/infant data; and (3) creating targets and evaluation goals for reporting progress on implementation and quality of surveillance in pregnancy. The platform will be leveraged to ensure that appropriate contributions and strategic actions by relevant stakeholders are implemented.

Prediction and prevention of preterm birth in pregnant women living with HIV on antiretroviral therapy

INTRODUCTION

The rate of spontaneous preterm-birth among pregnant women living with HIV on antiretroviral therapy (ART) is 3- to 4-fold higher when compared to HIV-negative women. The pathophysiology of preterm-birth related to HIV or ART remains unknown, especially as women living with HIV are often excluded from preterm birth studies.

AREAS COVERED

This review discusses the currently available evidence on the prediction and prevention of preterm-birth in pregnant women living with HIV. A review of the literature was conducted of primary articles between 2005 and 2021 measuring the association or lack thereof between combination ART and preterm birth, as well as of other predisposing factors to preterm birth in women living with HIV, including cervical length, vaginal microbiome, and cervico-vaginal biomarkers.

EXPERT OPINION

Further research into the effect of ART exposure on preterm-birth risk is critical, and development of preterm-birth predictive tools in this population should be a priority. Vaginal progesterone supplementation deserves further investigation as a therapeutic option to prevent recurrent preterm birth in pregnant women living with HIV. The ProSPAR study, a multicenter randomized controlled trial studying progesterone supplementation in pregnant women on protease inhibitor-based regimens, has been designed but is not yet recruiting patients.

Associations between HIV, antiretroviral therapy and preterm birth in the US Women's Interagency HIV Study, 1995-2018: a prospective cohort

OBJECTIVE

To evaluate the associations of HIV infection with preterm birth (PTB), and of HIV antiretroviral therapy (ART) with PTB.

METHODS

We analysed singleton live-born pregnancies among women from 1995 to 2019 in the Women's Interagency HIV Study, a prospective cohort of US women with, or at risk for, HIV. The primary exposures were HIV status and ART use before delivery [none, monotherapy or dual therapy, or highly active antiretroviral therapy (HAART)]. The primary outcome was PTB < 34 weeks, and, secondarily, < 28 and < 37 weeks. We analysed self-reported birth data, and separately modelled the associations between HIV and PTB, and between ART and PTB, among women with HIV. We used modified Poisson regression, and adjusted for age, race, parity, tobacco use and delivery year, and, when modelling the impact of ART, duration from HIV diagnosis to delivery, nadir CD4 count, and pre-pregnancy viral load and CD4 count.

RESULTS

We analysed 488 singleton deliveries (56% exposed to HIV) to 383 women. The risk of PTB < 34 weeks was similar among women with and without HIV, but the risk of PTB < 37 weeks was higher [32% vs. 23%; adjusted risk ratio (aRR) = 1.43; 95% confidence interval (CI): 1.07-1.91] among women with HIV. The risk of PTB < 34 weeks was lower among women with HIV receiving HAART than among those receiving no ART (7% vs. 26%; aRR:0.19; 95% CI: 0.08-0.44). The associations between HAART and PTB < 28 and < 37 weeks were similar.

CONCLUSIONS

Antiretroviral therapy exposure was associated with a decreased risk of PTB among a US cohort of women with HIV. Given the growing concerns about ART and adverse pregnancy outcomes, this finding that ART may be protective for PTB is reassuring.

Adverse pregnancy outcomes among pregnant women living with HIV in Hubei province, China: prevalence and risk factors

Mother-to-child transmission of Human Immunodeficiency Virus (HIV) has been greatly reduced with the advance of intervention technology. However, adverse pregnancy outcomes (APOs) are still common, and little is known about the driving forces of APOs among pregnant women living with HIV in China. Between January 2004 and December 2020, a total of 638 pregnancies among pregnant women living with HIV were enrolled in this study, 84 (13.2%) pregnancies with 87 APOs were reported. Preterm birth (3.8%), ectopic pregnancy (3.4%), spontaneous abortion (2.0%), and embryo arrest (1.7%) were the most common APOs in pregnant women living with HIV. Exposure to antiretroviral drugs (ARVs) during the first trimester (RR =  4.077, 95% CI: 0.521, 1.484, P<0.001) and the first CD4+ T lymphocyte count (CD4 count)≤ 350/μl (RR =  2.227, 95% CI: 0.063, 0.991, P = 0.026) were risk factors of APOs. The age≤ 30 years (RR =  -2.513, 95% CI: -1.067, -0.132, P = 0.012) was associated with the decreasing of APOs. Encouraging people to initiate combination antiretroviral therapy and reach a high CD4 count level before pregnancy would be helpful to prevent APOs. Pregnant women exposed to ARVs in the first trimester needed more attention for APOs.

Protease inhibitor-based antiretroviral therapy in pregnancy: effects on hormones, placenta, and decidua

The use of antiretroviral therapy (ART) in pregnancy is important for maternal health, and has been successful in reducing vertical transmission rates to almost zero in those taking effective ART regimens with good adherence. However, there are reports of higher rates of low birthweight and preterm births in women with HIV, which can be further exacerbated by ART usage in pregnancy. Protease inhibitors, and ritonavir-boosted lopinavir in particular, might directly contribute to placental and uteroplacental pathology in part by altering plasma concentrations of the essential steroid hormones of pregnancy, progesterone and oestradiol. In this Review, we collate the increasing evidence of dysregulated maternal endocrinology, reproductive physiology, and placental compromise associated with protease inhibitors. Based on findings of placental and decidual effects, we recommend that ritonavir-boosted lopinavir should be avoided in pregnancy, in line with US and European guidelines. Long-term follow-up of children exposed to protease inhibitors in utero is also recommended.

Adverse Pregnancy Outcomes Among HIV-positive Women in the Era of Universal Antiretroviral Therapy Remain Elevated Compared With HIV-negative Women

BACKGROUND

Without treatment, HIV infection in pregnant women is associated with adverse pregnancy outcomes. We compared adverse pregnancy outcomes among HIV-positive women on antiretroviral therapy (ART) and HIV-negative women who enrolled for antenatal care in selected health facilities in Maseru district, Lesotho.

METHODS

We enrolled a cohort of HIV-positive and HIV-negative women at their first antenatal visit and followed them through delivery. Study data on miscarriage, stillbirth, preterm birth, low birth weight and birth defects were collected through participant interviews and medical record abstraction. We used the Rao-Scott χ2 test and the t test to assess differences in characteristics and outcomes between HIV-positive and HIV-negative women and generalized estimating equations for multivariable analysis.

RESULTS

A total of 614 HIV-positive and 390 HIV-negative pregnant women were enrolled in the study with delivery information on 571 (93.1%) and 352 (90.3%) respectively. In the delivery cohort, the median age at enrolment was 28 years for HIV-positive women and 23 years for HIV-negative women with median gestational ages of 20 and 21 weeks, respectively. A total of 149 singleton pregnancies had documented adverse pregnancy outcomes; 33 (9.6%) HIV-negative pregnancies and 116 (20.6%) HIV-positive pregnancies. Compared with their HIV-negative counterparts, HIV-positive women were more likely to experience an adverse pregnancy outcome, adjusted odds ratio (AOR) 2.6 [95% confidence interval (CI): 1.71-3.97]; an intrauterine death (miscarriage or stillbirth), AOR 2.64 [95% CI: 1.25-5.49]; or a low birth weight delivery, AOR 1.89 [95% CI: 1.16-3.09].

CONCLUSION

Adverse pregnancy outcomes remained 2-3 times higher among HIV-positive women compared with HIV-negative women despite universal ART.

Reliability of last menstrual period recall, an early ultrasound and a Smartphone App in predicting date of delivery and classification of preterm and post-term births

Background

A reliable expected date of delivery (EDD) is important for pregnant women in planning for a safe delivery and critical for management of obstetric emergencies. We compared the accuracy of LMP recall, an early ultrasound (EUS) and a Smartphone App in predicting the EDD in South African pregnant women. We further evaluated the rates of preterm and post-term births based on using the different measures.

Methods

This is a retrospective sub-study of pregnant women enrolled in a randomized controlled trial between October 2017-December 2019. EDD and gestational age (GA) at delivery were calculated from EUS, LMP and Smartphone App. Data were analysed using SPSS version 25. A Bland–Altman plot was constructed to determine the limits of agreement between LMP and EUS.

Results

Three hundred twenty-five pregnant women who delivered at term (≥ 37 weeks by EUS) and without pregnancy complications were included in this analysis. Women had an EUS at a mean GA of 16 weeks and 3 days). The mean difference between LMP dating and EUS is 0.8 days with the limits of agreement 31.4–30.3 days (Concordance Correlation Co-efficient 0.835; 95%CI 0.802, 0.867). The mean(SD) of the marginal time distribution of the two methods differ significantly (p = 0.00187). EDDs were < 14 days of the actual date of delivery (ADD) for 287 (88.3%;95%CI 84.4–91.4), 279 (85.9%;95%CI 81.6–89.2) and 215 (66.2%;95%CI 60.9–71.1) women for EUS, Smartphone App and LMP respectively but overall agreement between EUS and LMP was only 46.5% using a five category scale for EDD-ADD with a kappa of .22. EUS 14–24 weeks and EUS < 14 weeks predicted EDDs < 14 days of ADD in 88.1% and 79.3% of women respectively. The proportion of births classified as preterm (< 37 weeks) was 9.9% (95%CI 7.1–13.6) by LMP and 0.3% (95%CI 0.1–1.7) by Smartphone App. The proportion of post-term (> 42 weeks gestation) births was 11.4% (95%CI 8.4–15.3), 1.9% (95%CI 0.9–3.9) and 3.4% (95%CI 1.9–5.9) by LMP, EUS and Smartphone respectively.

Conclusions

EUS and Smartphone App were the most accurate to estimate the EDD in pregnant women. LMP-based dating resulted in misclassification of a significantly greater number of preterm and post-term deliveries compared to EUS and the Smartphone App.

Profile of Chronic Comorbid Conditions and Obstetrical Complications Among Pregnant Women With Human Immunodeficiency Virus and Receiving Antiretroviral Therapy in the United States

BACKGROUND

To evaluate the frequency and associated characteristics of chronic comorbid conditions and obstetrical complications among pregnant women with human immunodeficiency virus (HIV) and receiving antiretroviral therapy (ART) in comparison to those without HIV.

METHODS

We compared 2 independent concurrent US pregnancy cohorts: (1) with HIV (International Maternal Pediatric Adolescent AIDS Clinical Trials Protocol P1025, 2002-2013) and (2) without HIV (Consortium for Safe Labor Study, 2002-2007). Outcomes were ≥2 chronic comorbid conditions and obstetrical complications. For women with HIV, we assessed whether late prenatal care (≥14 weeks), starting ART in an earlier era (2002-2008), and a detectable viral load at delivery (≥400 copies/mL) were associated with study outcomes.

RESULTS

We assessed 2868 deliveries (n = 2574 women) with HIV and receiving ART and 211 910 deliveries (n = 193 170 women) without HIV. Women with HIV were more likely to have ≥2 chronic comorbid conditions versus those without HIV (10 vs 3%; adjusted OR [AOR]: 2.96; 95% CI: 2.58-3.41). Women with HIV were slightly less likely to have obstetrical complications versus those without HIV (both 17%; AOR: .84; 95% CI: .75-.94), but secondarily, higher odds of preterm birth <37 weeks. Late entry to prenatal care and starting ART in an earlier era were associated with a lower likelihood of ≥2 chronic comorbidities and obstetrical complications; detectable viral load at delivery was associated with a higher likelihood of obstetric complications.

CONCLUSIONS

Pregnant women with HIV receiving ART have more chronic comorbid conditions, but not necessarily obstetrical complications, than their peers without HIV.