Every day in Uganda, FP averts approximately 20 vertical infections and 9 pediatric AIDS deaths. Our comparative analysis suggests that existing FP services significantly contribute to the goals of PMTCT in Uganda, exceeding the current achievements of ARV-PMTCT alone. Even the projected expansion of ARV uptake (in scale and quality) from 2008–2012 is matched by the effects of projected use of FP. At the same time, unwanted fertility in Uganda accounts for a substantial amount of pediatric HIV disease and will continue to do so unless access to FP services improves significantly. Targeting FP services for HIV-infected women could have a dramatic positive effect for PMTCT.
Our estimates' validity depends on the underlying formulas used in Spectrum as well as on the validity of the input data and underlying assumptions, such as MTCT probabilities or ARV-PMTCT uptake. The Spectrum software is reviewed by the UNAIDS Reference Group on Estimates, Models and Projections to ensure that it uses the latest data, recreates the pattern of historical epidemics and is consistent with other data sources such as estimates of AIDS mortality 
, the number of orphans and vulnerable children 
, and the number in need of ART 
. Most assumptions were adopted from the Spectrum software's default values which are based on review of international literature by expert panels. Although ante-natal clinic based HIV prevalence estimates have to be interpreted with caution 
, our estimates mainly rely on a national population-based HIV survey. We kept HIV prevalence stable over time as no new national estimates were available for the years after 2005. Although changes in HIV prevalence would affect the absolute size of estimates (e.g., number of vertical infections), they would have little impact on the relative effects (e.g., proportion of vertical infections averted) of ARV-PMTCT or FP and hence would not change the overall findings and conclusions. TFR was allowed to decline very slowly (as projected by the United Nations) whereas the uptake of combination ARVs steadily rose. The effect of ARV-PMTCT is particularly sensitive to its projected uptake until 2012. As mentioned, we chose a modest but realistic increase in ARV-PMTCT uptake and addressed the international goal of universal PMTCT coverage (corresponding to 80% uptake) in the context of a sensitivity analysis. This is because in order to meet Uganda's programmatic goals (including a reduction of vertical infections by 50% in 2011/2012 compared to 2006/2007), its national strategic plan 
for 2007–2012 calls for more than a three-fold increase in financial resources. Instead we chose what we thought to be a feasible increase in ARV-PMTCT uptake in an essentially flat funding environment for the foreseeable future. Changes in these and other parameters all affect the outcomes shown here although they would not alter the main conclusions. The inputed MTCT probabilities reflect findings from various trial data, implying that program effectiveness equals trial efficacies. PMTCT reports from Uganda however indicate that perhaps half of HIV-exposed newborns miss taking ARVs for PMTCT even though their mothers receive them 
, a factor we could not account for in our projections. Finally, better national data on FP service provision, access, and use, as well as TFR, childbearing desires, unintended pregnancies, and induced abortions among women at risk for or infected with HIV would have allowed a more refined analysis and a more informed discussion. Hopefully, such data will be become available in the future.
Our analysis on the effects of FP was limited to those relevant for pediatric HIV from 2007–2012. Because we left TFRc- and wTFR projections unchanged for historical years, we did not consider the effect of past contraceptive use or non-use (prior to 2007) on the current or future burden of pediatric HIV/AIDS. In fact, since the start of Uganda's HIV epidemic (assumed to be in 1980), contraceptive use likely averted a cumulative total of 280,000 vertical HIV infections and 180,000 pediatric AIDS deaths, while unwanted fertility led to 220,000 vertical infections and 140,000 pediatric AIDS deaths until 2009 (separate analysis, data not shown). We also did not consider other well described non HIV-specific benefits of FP such as improvement in gender inequality and female empowerment, reduction in overall child and maternal mortality, improving maternal health, as well as (indirectly) mitigating poverty, hunger, and facilitating universal primary education 
. Neither did we consider mistimed births, i.e., births occurring earlier than desired and easily avertable by family planning and part of the larger group of unintended pregnancies. Improved access to family planning would likely reduce the high maternal mortality (estimated at 550/100,000 live births 
) and abortion rate in Uganda, estimated at 54 per 1,000 women 
, translating into approximately 300,000 abortions per year, or one in five pregnancies. Elective abortions are illegal in Uganda 
, and thus are often carried out informally with greater risk for the mother.
The contribution of family planning for PMTCT gained substantial momentum in the literature in this decade 
. Reynolds et al. 
recently analyzed this topic for countries receiving funds from the United States PEPFAR (President's Emergency Plan For AIDS Relief) program, including Uganda, with similar conclusions as in our analysis.
The timing of events leading to an HIV-infected child (HIV acquisition by a woman of reproductive age, followed by pregnancy and subsequent MTCT), makes it clear that family planning for PMTCT is entirely complementary to ARV-based PMTCT. Because family planning precedes ARV-based PMTCT in sequential order, reducing unwanted pregnancies alleviates the resource-intensive ante-natal clinic and ARV-based PMTCT services. Uganda's CPR (contraceptive prevalence rate) is estimated at just 19.6% 
including traditional methods (4.1%); a CPR increase to 34% (or 41% among currently married women) is necessary to reach the total wanted fertility rate of 5.1 that was used in this analysis. Most HIV-infected Ugandan women of reproductive age are unaware of their HIV status and many would opt for FP if they knew their serostatus or had better access to FP. An immediate and targeted measure calls for better – real – integration of FP services into post-natal care for HIV-positive and indeed all sexually active women of reproductive age. However, PMTCT funds have not been available for this purpose in Uganda 
, not least as some donors do not allow for the procurement of family planning commodities. PMTCT training curricula need to address all four PMTCT pillars as should monitoring and evaluation programs reviewing PMTCT services. Voluntary counseling and testing programs actively offering FP services to HIV-infected adults would avert many subsequent unwanted HIV-positive pregnancies. Moreover, given the risk of HIV transmission associated with unprotected sex, the promotion of dual family planning (the combined use of a barrier with a hormonal FP method) would achieve reductions in both vertical and horizontal HIV infections. Lastly, a general investment to expand FP services for all sexually active persons may yield the broadest benefits for HIV-positive and negative women alike, averting transmission in HIV-discordant relationships and unintended pregnancies (irrespective of HIV status) and its many consequences.
Even the planned expansion of ARV-PMTCT uptake to 80% by itself is unlikely to achieve Uganda's goal to reduce MTCT by 50% 
. Comprehensive PMTCT that includes both ARV prophylaxis and FP services is needed to make such goals achievable. Modern FP methods are safe, cost-effective 
, and provide substantial benefits towards PMTCT and beyond. These data demonstrate the substantial potential benefit of increasing FP coverage on reducing HIV infections in children in Uganda. Better integration of FP with PMTCT programs would be an important way to achieve this benefit. Donors, policy makers, and program planners need to acknowledge and embrace the real contribution of FP for PMTCT and support its expansion.