Effect of Gestational Age at Tenofovir-Emtricitabine-Efavirenz Initiation on Adverse Birth Outcomes in Botswana

Adverse perinatal outcomes associated with timing of initiation of antiretroviral therapy: Systematic review and meta-analysis

BACKGROUND

The World Health Organization (WHO) recommends immediate initiation of lifelong antiretroviral therapy (ART) for all people living with HIV, including pregnant women. As a result, an increasing number of women living with HIV conceive while taking ART, the vast majority of whom reside in low- and middle-income countries (LMICs). We aimed to assess the association between timing of ART initiation and perinatal outcomes.

METHODS

We conducted a systematic literature review by searching PubMed, CINAHL (EBSCOhost), Global Health (Ovid), EMBASE (Ovid), and the Cochrane Central Register of Controlled Trials and four clinical trial databases (WHO International Clinical Trials Registry Platform, the Pan African Clinical Trials Registry, the ClinicalTrials.gov database, and the ISRCTN Registry) from 1 January 1980 to 28 April 2018. We identified studies reporting specific perinatal outcomes among pregnant women living with HIV according to timing of ART initiation and extracted data. Perinatal outcomes assessed were preterm birth (<37 weeks), very preterm birth (<32 weeks), low birthweight (<2500 g), very low birthweight (<1500 g), small for gestational age (<10^th centile), very small for gestational age (<3^rd centile) and neonatal death (<29 days). Random-effects meta-analyses examined perinatal outcomes associated with preconception and antenatal ART initiation as well as according to trimesters of antenatal initiation. We performed quality assessments and subgroup and sensitivity analyses, and assessed the effect of adjustment for confounders. This systematic review and meta-analyses is registered with PROSPERO, number CRD42021248987.

RESULTS

Of 51 874 unique citations, 25 studies (eight prospective and 17 retrospective cohort studies) were eligible for analysis, including 40 920 women living with HIV. Preconception ART initiation was associated with a significantly increased risk of preterm birth (relative risk 1.16; 95% confidence interval [CI] 1.03-1.31) compared with antenatal ART initiation. Preconception ART initiation was not significantly associated with very preterm birth, low birthweight, very low birthweight, small for gestational age, very small for gestational age, or neonatal death. First trimester exposure (i.e. preconception or first trimester initiation) was not significantly associated with any increased risk of adverse perinatal outcomes. No significant association between timing of ART initiation and adverse perinatal outcomes was found in the studies of higher quality and those conducted in LMICs.

CONCLUSION

Preconception ART initiation is associated with preterm birth but no other adverse perinatal outcomes. In LMICs, where most pregnant women living with HIV reside, the timing of ART initiation was not associated with any adverse perinatal outcomes.

A Scoping Review of Preterm Births in Sub-Saharan Africa: Burden, Risk Factors and Outcomes

Preterm births (PTB) are the leading cause of neonatal deaths, the majority of which occur in low- and middle-income countries, particularly those in Sub-Saharan Africa (SSA). Understanding the epidemiology of prematurity is an essential step towards tackling the challenge of PTB in the sub-continent. We performed a scoping review of the burden, predictors and outcomes of PTB in SSA. We searched PubMed, Embase, and three other databases for articles published from the database inception to 10 July 2021. Studies reporting the prevalence of PTB, the associated risk factors, and/or its outcomes were eligible for inclusion in this review. Our literature search identified 4441 publications, but only 181 met the inclusion criteria. Last menstrual period (LMP) was the most commonly used method of estimating gestational age. The prevalence of PTB in SSA ranged from 3.4% to 49.4%. Several risk factors of PTB were identified in this review. The most frequently reported risk factors (i.e., reported in ≥10 studies) were previous history of PTB, underutilization of antenatal care (<4 visits), premature rupture of membrane, maternal age (≤20 or ≥35 years), inter-pregnancy interval, malaria, HIV and hypertension in pregnancy. Premature babies had high rates of hospital admissions, were at risk of poor growth and development, and were also at a high risk of morbidity and mortality. There is a high burden of PTB in SSA. The true burden of PTB is underestimated due to the widespread use of LMP, an unreliable and often inaccurate method for estimating gestational age. The associated risk factors for PTB are mostly modifiable and require an all-inclusive intervention to reduce the burden and improve outcomes in SSA.

Timing of Antiretroviral Therapy: Initiation and Birth Outcomes Among Pregnant Women With Human Immunodeficiency Virus in Tanzania

BACKGROUND

Combination antiretroviral therapy (cART) initiation during pregnancy reduces the risk of perinatal human immunodeficiency virus (HIV) transmission; however, studies have suggested that there may be unintended adverse consequences on birth outcomes for selected cART regimens.

METHODS

We analyzed adverse birth outcomes among a prospective cohort of 1307 pregnant women with HIV in Dar es Salaam who initiated cART during the first or second trimester of a singleton pregnancy. Our primary analysis compared birth outcomes by gestational age at cART initiation among these women initiating cART in pregnancy.

RESULTS

Among women who initiated cART in pregnancy, there was no relationship of gestational age at cART initiation with the risk of fetal death or stillbirth. However, women who initiated cART before 20 weeks of gestation compared with after 20 weeks had increased risk of preterm birth (risk ratio [RR], 1.30; 95% confidence interval [CI], 1.03-1.67) but decreased risk of small-for-gestational age birth (RR, 0.71; 95% CI, .55-.93).

CONCLUSIONS

With increasing use of cART preconception and early in pregnancy, clinicians should be aware of the benefits and potential risks of cART regimens to optimize birth outcomes.

No Difference in Growth Outcomes up to 24 Months of Age by Duration of Exposure to Maternal Antiretroviral Therapy Among Children Who Are HIV-Exposed and Uninfected in Malawi

BACKGROUND

With the implementation of lifelong antiretroviral therapy (ART) for HIV treatment and prevention, the proportion of children exposed to ART in utero from conception is increasing. We estimated the effect of timing of ART exposure on growth of children HIV-exposed and uninfected (CHEU) up to Up to 24 months of age in Malawi.

METHODS

Data were collected from a prospective cohort of infants HIV-exposed aged 1-6 months (enrollment) and their mothers with HIV enrolled in the National Evaluation of Malawi's Prevention of Mother-to-Child Transmission of HIV Programme (2014-2018). Anthropometry was measured at enrollment, visit 1 (approximately 12 months), and visit 2 (approximately 24 months). Weight-for-age (WAZ) and length-for-age (LAZ) were calculated using the WHO Growth Standards. Multivariable mixed-effects models with linear splines for age were used to examine differences in growth by timing of ART exposure (from conception, first/second trimester, or third trimester/postpartum). Models were adjusted for confounders selected a priori guided by a conceptual framework. Hypothesized interactions and potential mediators were explored, and interactions with splines were included in final models if P < 0.1.

RESULTS

A total of 1,206 singleton CHEU and their mothers were enrolled and 563 completed the follow-up through 24 months of age. Moreover, 48% of CHEU were exposed to ART from conception, 40% from first/second trimester, and 12% from third trimester/postpartum. At enrollment, 12% of infants had low birthweight (LBW), 98% had been breastfed in past 7 days, and 57% were enrolled in an HIV care clinic. CHEU growth trajectories demonstrated cohort-wide growth faltering after the age of 12 months. Of 788 and 780 CHEU contributing to WAZ and LAZ multivariable models, respectively, there was no evidence of differences in mean WAZ or LAZ among those exposed from conception or first/second trimester vs. third trimester/postpartum and no evidence of a difference in WAZ or LAZ rate of change by timing of ART exposure (all interactions P > 1.0).

CONCLUSION

Reassuringly, ART exposure from conception was not associated with decreased WAZ or LAZ in CHEU Up 24 months of age. Overall growth trajectories suggest CHEU experience growth faltering after 12 months of age and may need support through and beyond the first 2 years of life.

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.

Perinatal outcomes associated with maternal HIV and antiretroviral therapy in pregnancies with accurate gestational age in South Africa

OBJECTIVE

To assess the association of maternal HIV infection and antiretroviral therapy (ART) with perinatal outcomes among women with accurate pregnancy dating and birth weights.

DESIGN

Prospective pregnancy cohort study in Soweto, South Africa.

METHODS

Gestational age was estimated by first-trimester ultrasound and birth weight was measured in a standardized manner within 24 h of birth. The primary composite outcome 'adverse perinatal outcome' included preterm birth, low birth weight, small for gestational age, stillbirth and neonatal death (NND). Specific adverse perinatal outcomes were secondary outcomes. Logistic regression models adjusted for multiple confounders.

RESULTS

Of 633 women included in the analysis, 229 (36.2%) were HIV positive and 404 (63.8%) HIV negative. Among 125 HIV-positive women who provided detailed information on HIV and ART, 96.7% had clinical stage 1 of HIV disease and 98.4% were on ART during pregnancy, mostly WHO-recommended efavirenz-based ART. Among 109 HIV-positive women with information on timing of ART initiation, 38 (34.9%) initiated ART preconception and 71 (65.1%) antenatally. No newborns were HIV positive. In univariable analysis, maternal HIV infection was associated with increased risk of the composite 'adverse perinatal outcome' [odds ratio (OR) 1.44; 95% confidence interval (CI) 1.03, 2.03], NND (OR 6.15; 95% CI 1.27, 29.88) and small for gestational age (OR 1.55; 95% CI 1.01, 2.37). After adjusting for confounders, maternal HIV infection remained associated with 'adverse perinatal outcome' (adjusted OR 1.47; 95% CI 1.01, 2.14) and NND (adjusted OR 7.82; 95% CI 1.32, 46.42). No associations with timing of ART initiation were observed.

CONCLUSION

Despite high ART coverage, good maternal health and very low vertical HIV transmission rate, maternal HIV infection remained associated with increased risk of adverse perinatal outcomes. Larger studies using first trimester ultrasound for pregnancy dating are needed to further assess associations with specific adverse perinatal outcomes.