Table 3. Incidence rates (IRs) of unexpected vaginal bleeding per 100 person years (PY) and HR with 95% CI by vaccination status, in all, post-, peri-, and premenopausal women.

cHR, crude HR; aHR, HR adjusted for age. For additional adjustment, see table S2.

	Events	PY	IR per 100 PY (95% CI)	cHR (95% CI)	aHR (95% CI)
Postmenopausal (n = 7725)
Non/prevaccination	108	2724	4.0 (3.3–4.8)	Ref	Ref
First dose, ≤28 days	69	579	11.9 (9.4–15.1)	2.3 (1.5–3.3)	3.0 (2.0–4.4)
First dose, >28 days	10	413	2.4 (1.3–4.5)	0.4 (0.2–0.9)	0.6 (0.3–1.2)
Second dose, ≤28 days	44	486	9.0 (6.7–12.2)	1.3 (0.8–2.1)	2.2 (1.4–3.5)
Second dose, >28 days	21	1025	2.0 (1.3–3.1)	0.3 (0.2–0.5)	0.8 (0.4–1.4)
Total	252	5228	4.8 (4.3–5.5)
Perimenopausal (n = 7148)
Non/prevaccination	379	2827	13.4 (12.1–14.8)	Ref	Ref
First dose, ≤28 days	312	504	62.0 (55.4–69.2)	4.2 (3.5–5.2)	4.2 (3.5–5.2)
First dose, >28 days	32	398	8.0 (5.7–11.4)	0.6 (0.4–0.9)	0.6 (0.4–0.9)
Second dose, ≤28 days	204	357	57.2 (49.8–65.6)	3.7 (2.9–4.7)	3.7 (2.9–4.7)
Second dose, >28 days	81	422	19.2 (15.4–23.9)	1.3 (1.0–1.8)	1.3 (1.0–1.8)
Total	1008	4508	22.4 (21.0–23.8)
Premenopausal, nonmenstruating (n = 7052)
Non/prevaccination	323	2814	11.5 (10.3–12.8)	Ref	Ref
First dose, ≤28 days	310	497	62.4 (55.8–69.8)	4.6 (3.8–5.6)	4.7 (3.8–5.7)
First dose, >28 days	24	353	6.7 (4.6–10.1)	0.5 (0.3–0.8)	0.5 (0.4–0.9)
Second dose, ≤28 days	201	336	59.9 (52.2–68.8)	4.1 (3.2–5.2)	4.2 (3.3–5.2)
Second dose, >28 days	66	474	13.9 (10.9–17.7)	1.0 (0.7–1.3)	1.0 (0.7–1.3)
Total	924	4474	20.7 (19.4–22.0)