Table 3 Incidence rate ratios (IRR) for loss to follow-up in first 6 months after first ANC among adolescent and young women living with HIV (AYWLH) < 25 years among those with antiretroviral therapy (ART) start dates by age group, Kenya (N = 543)
|  | AYWLH < 20 years of age | AYWLH 20–24 years of age | ||||
|---|---|---|---|---|---|---|
Adjusted incidence rate ratio | 95%CI | p-value | Adjusted incidence rate ratio | 95%CI | p-value | |
Pre-period vs. Post-period (all post-period AYWLH) | ||||||
 Post-period (ref: pre-period) | 0.62 | 0.38–1.01 | 0.057 | 1.18 | 0.72–1.94 | 0.50 |
  Gestational age weeks | 0.96 | 0.88–1.05 | 0.42 | 0.99 | 0.97–1.02 | 0.65 |
  Parity 1 + (ref: 0) | 0.16 | 0.02–1.12 | 0.07 | 1.02 | 0.48–2.16 | 0.96 |
  Known HIV + at first ANC (ref: newly diagnosed) | 0.08 | 0.02–0.37 |  < 0.01 | 0.40 | 0.15–1.04 | 0.06 |
  On ART at first ANC (ref: started ART first ANC) | 2.83 | 0.62–12.98 | 0.18 | 0.66 | 0.44–0.98 | 0.04 |
Pre-period vs. Post-period (women attending HOPE) | ||||||
 Post-period (ref: pre-period) | 0.41 | 0.08–2.05 | 0.28 | 0.85 | 0.46–1.57 | 0.60 |
  Gestational age weeks | 0.98 | 0.90–1.08 | 0.71 | 0.99 | 0.96–1.01 | 0.30 |
  Parity 1 + (ref: 0) | 0.23 | 0.02–2.09 | 0.18 | 0.98 | 0.41–2.35 | 0.97 |
  Known HIV + at first ANC (ref: newly diagnosed) | – | – | – | 0.52 | 0.16–1.71 | 0.29 |
  On ART at first ANC (ref: started ART first ANC) | 1.89 | 0.19–18.98 | 0.59 | 0.50 | 0.31–0.80 |  < 0.01 |