Table 1.

Patient characteristics for the overall sample and stratified by intermenstrual bleeding¹

Characteristic	Overall (n=549)	No IM Bleeding (n=336)	IM Bleeding (n=204)	P value	No luteal bleeding (n=357)	Luteal bleeding (n=187)	P value
Age (years)				0.99			0.90
<35	68%	68%	69%		68%	69%
35-37	19%	19%	18%		19%	18%
>37	13%	13%	13%		13%	13%
Race				0.47			0.17
Non-Hispanic Caucasian	77%	77%	75%		78%	73%
Other	23%	23%	25%		22%	27%
Education level				0.83			0.64
Less than college degree	7%	7%	8%		7%	8%
College degree	20%	20%	19%		21%	17%
Some graduate work	10%	10%	11%		10%	11%
Completed postgraduate	63%	63%	62%		62%	64%
Gravid				0.59			0.24
No	49%	48%	50%		47%	52%
Yes	51%	52%	50%		53%	48%
BMI (kg/m2)				0.09			0.17
<18.5	3%	2%	4%		2%	4%
18.5-24.9	60%	58%	64%		57%	65%
25-29.9	21%	24%	16%		24%	17%
≥30	16%	16%	16%		17%	14%
Current smoking				0.09			0.09
No	99%	98%	100%		98%	100%
Yes	1%	2%	0%		2%	0%
Attempt cycle at study entry				0.76			0.81
1	17%	17%	16%		17%	17%
2	43%	44%	41%		44%	40%
3	22%	21%	25%		21%	25%
4	12%	11%	12%		11%	12%
5	6%	7%	5%		6%	6%
Recent hormone contraception2				0.59			0.93
No	55%	54%	57%		55%	56%
Yes	45%	46%	43%		45%	44%
Mean cycle length (days ± SD)	29 (2)	29 (2)	29(2)	0.67	29 (2)	29 (2)	0.47
Mean menses length (days ± SD)	5 (1)	5 (1)	5 (1)	0.77	5 (1)	5 (1)	0.58
Mean intercourse days (days ± SD)	7 (4)	7 (4)	6 (4)	0.26	7 (4)	6 (4)	0.34
Tested for pregnancy (at least once)				0.86			0.18
No	42%	42%	43%		40%	47%
Yes	58%	58%	57%		60%	53%
Partner’s age (years)				0.72			0.72
<50	99%	98%	99%		98%	99%
≥50	1%	2%	1%		2%	1%
Partner race				0.54			0.92
Non-Hispanic Caucasian	76%	74%	77%		75%	76%
Other	24%	26%	23%		25%	24%
Partner education level				0.77			0.42
Less than college degree	17%	18%	15%		18%	14%
College degree	28%	29%	27%		30%	26%
Some graduate/masters	9%	9%	9%		8%	10%
Completed postgraduate	46%	44%	49%		44%	50%

IM, intermenstrual

¹Patient characteristics in the first complete study cycle

²Oral contraceptive pills, contraceptive patch, or contraceptive vaginal ring use in the past year