Factors associated with regularity and length of menstrual cycle: Korea Nurses’ Health Study

BMC Women's Health

Table 3 Least-square means of menstrual distress and perceived health status according to the menstrual cycle characteristics

Multivariable-adjusted LSmeans ± SE	Menstrual cycle regularity			Menstrual cycle length
Multivariable-adjusted LSmeans ± SE	Regular (n = 7359)	Irregular (n = 1976)	p value	< 26 days (n = 886)	26–31 days (n = 5794)	32–50 days (n = 2363)	p value	P for trend
Menstrual distress
Most recent flow	31.94 ± 0.55	35.75 ± 0.75	< 0.001	35.78 ± 1.01^a	31.80 ± 0.58^a,b	33.54 ± 0.72^b	< 0.001	0.840
Four days before flow	24.69 ± 0.54	29.47 ± 0.74	< 0.001	29.05 ± 1.00^a	24.53 ± 0.57^a,b	27.16 ± 0.70^b	< 0.001	0.234
Perceived health status
Depressive symptoms	7.01 ± 0.11	7.73 ± 0.15	< 0.001	7.34 ± 0.20	7.04 ± 0.12	7.16 ± 0.14	0.260	0.996
Perceived stress	6.49 ± 0.05	6.82 ± 0.06	< 0.001	6.84 ± 0.09^a,c	6.52 ± 0.05^a	6.53 ± 0.06^c	0.001	0.057
Physical fatigue	12.00 ± 0.08	12.54 ± 0.11	< 0.001	12.17 ± 0.15	12.07 ± 0.09	12.11 ± 0.11	0.783	0.968
Mental fatigue	5.55 ± 0.05	5.84 ± 0.07	< 0.001	5.82 ± 0.10^a	5.58 ± 0.06^a	5.60 ± 0.07	0.040	0.255
Anxiety	15.03 ± 0.06	15.46 ± 0.08	< 0.001	15.30 ± 0.11	15.08 ± 0.06	15.09 ± 0.08	0.098	0.292
Sleep problems	10.41 ± 0.10	11.20 ± 0.14	< 0.001	10.39 ± 0.19	10.50 ± 0.11	10.69 ± 0.13	0.202	0.074

Adjusted for age (years), age at menarche (≤ 12, 13, 14, or ≥ 15 years), parity (nulliparous, 1, or 2+), body mass index (kg/m²), vigorous physical activity (none or tertiles), and alcohol consumption (0, < 5, 5– < 15, or ≥ 15 g/day)
Missing data: menstrual distress-most recent flow (n = 1), depressive symptoms (n = 9), physical or mental fatigue, anxiety, and sleep problems (n = 1 for each)
LSmeans, Least-square means; SE, standard error
^aSignificantly different between < 26 days and 26–31 days (p < 0.05, post Bonferroni correction)
^bSignificantly different between 32–50 days and 26–31 days
^cSignificantly different between < 26 days and 32–50 days

ISSN: 1472-6874