2%, and <1% among women who had received at least 14 days of ART. Among more than 2000 women who had received HAART and delivered with an undetectable VL, there were only three transmissions, an MTCT rate of 0.1% [4]. These very low transmission rates persist. A small proportion of HIV-positive women remain undiagnosed at delivery in the UK, which probably means that currently about 2% of all HIV-exposed infants (born to diagnosed and undiagnosed women) are vertically infected [1]. By 2010, over 98% of all diagnosed women received some form of ART before delivery: the proportion of those who were taking zidovudine

monotherapy dropped from about 20% in 2002–2003 to <5% since 2006, and only about 2% in 2009–2010. Over the same period the proportion of women delivering by elective CS declined from about two-thirds CHIR-99021 chemical structure to just over one-third, while vaginal deliveries increased from <15% of all deliveries to almost 40%. Although planned vaginal Selleck Akt inhibitor delivery is now common for women who are on HAART with undetectable VL close to delivery, the increase in planned vaginal deliveries may have contributed to a rise in reported emergency CS, from about 20% to 25% [5].

Between 2005 and 2010 between 1100 and 1300 children were born each year in the UK to diagnosed HIV-positive women. Since virtually all diagnosed women in the last decade have taken ART to reduce the risk of MTCT, almost all of these children are uninfected. However, this means there are, in 2011, over 11 000 HIV-exposed uninfected children in the UK whose mothers conceived on combination ART (cART), or started ART during pregnancy [5]. The number of children diagnosed with vertically acquired HIV infection in the UK increased from about 70 a year in the early 1990s to a peak of 152 in 2004, and declined to 82 in 2009 [6]. During the last decade, about two-thirds of newly diagnosed children were born abroad. Owing to the increasing prevalence of maternal infection, combined Ureohydrolase with increasing maternal diagnosis rates and decreasing MTCT rates, the estimated number of infected children born in

the UK has remained stable over the last decade, at about 30–40 a year. More than 300 children have also been reported, mostly in the early years of the epidemic, with non-vertically acquired infection, the majority from blood or blood products. Among HIV-positive children with follow-up care in the UK and Ireland, the rate of AIDS and mortality combined declined from 13.3 cases per 100 person years before 1997 to 2.5 per 100 person years in 2003–2006 [7]. With improving survival, the median age of children in follow-up increased from 5 years in 1996 to 12 years in 2010, by which time over 300 young people had transferred to adult care [8]. Pregnancies in vertically infected young women are now occurring [9].