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Background: A trial of progesterone to prevent preterm birth among HIV-infected Zambian women [Improving Pregnancy Outcomes with Progesterone (IPOP)] found no treatment effect, but the risk of the primary outcome was among the lowest ever documented in women with HIV. In this secondary analysis, we compare the risks of preterm birth (<37 weeks), stillbirth, and a composite primary outcome comprising the two in IPOP versus an observational pregnancy cohort [Zambian Preterm Birth Prevention Study (ZAPPS)] in Zambia, to evaluate reasons for the low risk in IPOP.Methods: Both studies enrolled women before 24 gestational weeks, during August 2015-September 2017 (ZAPPS) and February 2018-January 2020 (IPOP). We used linear probability and log-binomial regression to estimate risk differences and risk ratios (RR), before and after restriction and standardization with inverse probability weights.Results: The unadjusted risk of composite outcome was 18% in ZAPPS (N = 1450) and 9% in IPOP (N = 791) (RR = 2.0; 95% CI = 1.6, 2.6). After restricting and standardizing the ZAPPS cohort to the distribution of IPOP baseline characteristics, the risk remained higher in ZAPPS (RR = 1.6; 95% CI = 1.0, 2.4). The lower risk of preterm/stillbirth in IPOP was only partially explained by measured risk factors.Conclusions: Possible benefits in IPOP of additional monetary reimbursement, more frequent visits, and group-based care warrant further investigation. [ABSTRACT FROM AUTHOR]

Objective: We investigated the effect of maternal HIV and its treatment on spontaneous and provider-initiated preterm birth (PTB) in an urban African cohort. Methods: The Zambian Preterm Birth Prevention Study enrolled pregnant women at their first antenatal visit in Lusaka. Participants underwent ultrasound, laboratory testing, and clinical phenotyping of delivery outcomes. Key exposures were maternal HIV serostatus and timing of antiretroviral therapy initiation. We defined the primary outcome, PTB, as delivery between 16 and 37 weeks' gestational age, and differentiated spontaneous from provider-initiated parturition. Results: Of 1450 pregnant women enrolled, 350 (24%) had HIV. About 1216 (84%) were retained at delivery, 3 of whom delivered, 16 weeks. Of 181 (15%) preterm deliveries, 120 (66%) were spontaneous, 56 (31%) were provider-initiated, and 5 (3%) were unclassified. In standardized analyses using inverse probability weighting, maternal HIV increased the risk of spontaneous PTB [RR 1.68; 95% confidence interval (CI): 1.12 to 2.52], but this effect was mitigated on overall PTB [risk ratio (RR) 1.31; 95% CI: 0.92 to 1.86] owing to a protective effect against provider-initiated PTB. HIV reduced the risk of preeclampsia (RR 0.32; 95% CI: 0.11 to 0.91), which strongly predicted providerinitiated PTB (RR 17.92; 95% CI: 8.13 to 39.53). The timing of antiretroviral therapy start did not affect the relationship between HIV and PTB. Conclusion: The risk of HIV on spontaneous PTB seems to be opposed by a protective effect of HIV on provider-initiated PTB. These findings support an inflammatory mechanism underlying HIVrelated PTB and suggest that published estimates of PTB risk overall underestimate the risk of spontaneous PTB. [ABSTRACT FROM AUTHOR]

Background: Investigations of the association of combination antiretroviral therapy (ART) with pregnancy outcomes often rely on routinely collected clinical data, which are prone to missing data and measurement error. Measurement error in gestational age may bias the relation between combination ART and gestational age-based outcomes.Methods: We demonstrate the use of multiple overimputation to address missing data and measurement error in gestational age. Using routinely collected clinical data from public health facilities in Lusaka, Zambia, we multiply imputed missing data and multiply overimputed observed values of gestational age. Poisson models with robust variance estimators were used to estimate risk ratios (RRs) for the associations of duration of combination ART with small for gestational age (SGA) and preterm birth. We compared results from a complete-case analysis, using multiple imputation to address missing data only and using multiple overimputation to address missing data and measurement error.Results: In the complete-case analysis, there was no evidence of an association between duration of combination ART and SGA or preterm birth. When we performed multiple overimputation, RRs for SGA moved past the null, but remained imprecise. For preterm birth, RRs for 9-32 weeks of combination ART moved away from the null as the variance due to measurement error increased.Conclusion: When we used multiple overimputation to account for measurement error and missing data, we observed an increased risk of preterm birth with longer duration of combination ART. Future analyses examining associations between combination ART and pregnancy outcomes should consider using multiple overimputation to address measurement error in gestational age. [ABSTRACT FROM AUTHOR]

To evaluate the impact of family planning promotion on incident pregnancy in a combined effort to address Prongs 1 and 2 of prevention of mother-to-child transmission of HIV.We conducted a factorial randomized controlled trial of 2 video-based interventions.“Methods” and “Motivational” messages promoted long-term contraceptive use among 1060 couples with HIV in Lusaka, Zambia.Among couples not using contraception before randomization (n = 782), the video interventions had no impact on incident pregnancy. Among baseline contraceptive users, viewing the “Methods video” which focused on the intrauterine device and contraceptive implant was associated with a significantly lower pregnancy incidence [hazard ratio (HR) = 0.38; 95% confidence interval (CI): 0.19 to 0.75] relative to those viewing control and/or motivational videos. The effect was strongest in concordant positive couples (HR = 0.22; 95% CI: 0.08 to 0.58) and couples with HIV-positive women (HR = 0.23; 95% CI: 0.09 to 0.55).The “Methods video” intervention was previously shown to increase uptake of long-acting contraception and to prompt a shift from daily oral contraceptives to quarterly injectables and long-acting methods such as the intrauterine device and implant. Follow-up confirms sustained intervention impact on pregnancy incidence among baseline contraceptive users, in particular couples with HIV-positive women. Further work is needed to identify effective interventions to promote long-acting contraception among couples who have not yet adopted modern methods. [ABSTRACT FROM AUTHOR]

The article presents a retrospective cohort study conducted in Lusaka, Zambia to determine the rates and determinants of stillbirth in the area's urban obstetric population. Based on the analysis, stillbirth is associated to such factors as placental abruption, cesarean delivery and operative vaginal delivery. Stillbirth or fetal death is defined by the International Classification of Disease as the death of a fetus who has reached 22 weeks of completed gestation or weighs at least 500 grams (g).

Objective: Male circumcision reduces female-to-male HIV-1 transmission risk by approximately 60%. Data assessing the effect of circumcision on male-to-female HIV-1 transmission are conflicting, with one observational study among HIV-1-serodiscordant couples showing reduced transmission but a randomized trial suggesting no short-term benefit of circumcision., Design/methods: Data collected as part of a prospective study among African HIV-1-serodiscordant couples were analyzed for the relationship between circumcision status of HIV-1-seropositive men and risk of HIV-1 acquisition among their female partners. Circumcision status was determined by physical examination. Cox proportional hazards analysis was used., Results: A total of 1096 HIV-1-serodiscordant couples in which the male partner was HIV-1-infected were followed for a median of 18 months; 374 (34%) male partners were circumcised. Sixty-four female partners seroconverted to HIV-1 (incidence 3.8 per 100 person-years). Circumcision of the male partner was associated with a nonstatistically significant approximately 40% lower risk of HIV-1 acquisition by the female partner (hazard ratio 0.62, 95% confidence interval 0.35-1.10, P = 0.10). The magnitude of this effect was similar when restricted to the subset of HIV-1 transmission events confirmed by viral sequencing to have occurred within the partnership (n = 50, hazard ratio 0.57, P = 0.11), after adjustment for male partner plasma HIV-1 concentrations (hazard ratio 0.60, P = 0.13), and when excluding follow-up time for male partners who initiated antiretroviral therapy (hazard ratio 0.53, P = 0.07)., Conclusion: Among HIV-1-serodiscordant couples in which the HIV-1-seropositive partner was male, we observed no increased risk and potentially decreased risk from circumcision on male-to-female transmission of HIV-1.