HIV testing during labour and delivery provides a critical opportunity for administering appropriate interventions to prevent mother-to-child-transmission (PMTCT). We studied current HIV rates and infection trend among women tested during delivery following scale-up of PMTCT and antiretroviral therapy (ART) programs in Jos, north central Nigeria. Between March 2010 and January 2012, provider-initiated HIV testing and counselling was offered in early labour. Women were recruited from a government tertiary health centre, a faith-based hospital, and a private health centre. Those who previously tested HIV negative during antenatal care (ANC) and those who presented at the labour ward with unknown HIV status were tested. A total of 944 subjects (727 re-tested for HIV infection and 217 with unknown HIV status) were enrolled and tested during labour. The HIV incidence and sero-conversion rates during pregnancy among women who repeated HIV testing at delivery was 1.7 per 100 person-years of observation (pyo) and 0.6% (4/727), respectively, while the rate among those who tested for the first time in labour was 1.8% (4/217). Women who accessed ANC were older and had achieved a higher educational status than those who did not access ANC. A 3- to 5-fold decline in HIV incidence and prevalence rates was detected among women tested at delivery when compared to data from a report in 2004. It is not certain whether the decline in maternal HIV infection is due to the major state-wide scale-up of PMTCT and HIV treatment programs. A broader and purposefully designed evaluation study would be required to verify observed occurrence.