Association of Asthma Diagnosis and Medication Use with Fecundability: A Prospective Cohort Study

Figures & data

Table 1 Baseline Characteristics^a of 8286 Female Pregnancy Planners by Asthma Diagnosis and Medication Use

Characteristic	Asthma Medication Use
	Asthma Diagnosis and Medication Use in Last 4 Weeks				Asthma Diagnosis and no Medication Use in Last 4 Weeks	No Asthma Diagnosis
	When Having Symptoms	Daily	Daily & When Having Symptoms	Overall
n (%)	272	95	97	469 (5.7)	912 (11.0)	6905 (83.3)
Proportion of those with asthma diagnosis^b	19.7	6.9	7.0	34.0	66.0	N/A
Age at baseline (years), mean	29.5	30.4	30.1	29.8	29.5	29.9
Age at asthma diagnosis, mean	14.1	14.9	14.6	14.5	12.7	N/A
Education, %
Less than college	6.4	7.4	7.5	7.0	4.9	5.2
Some college	31.6	25.7	24.8	28.9	22.7	22.3
College graduate	28.2	25.3	37.3	28.9	34.5	34.6
Graduate school	33.8	41.5	30.4	35.1	37.8	37.9
Household income (US dollars/year), %
<50,000	29.0	27.7	25.5	28.4	21.4	19.9
50,000–99,999	37.4	35.6	43.2	37.6	37.4	38.8
100,000–149,000	23.1	28.3	17.2	23.2	24.4	25.9
≥150,000	10.5	8.4	14.1	10.8	16.7	15.4
Primary care provider visits, past year, %
0	8.7	3.3	2.1	6.1	10.5	12.1
1	20.3	18.8	17.5	19.1	27.8	31.9
2–3	46.0	47.4	46.0	46.3	42.4	40.5
4–5	15.1	20.3	17.5	17.0	11.9	9.3
≥6	10.0	10.3	16.9	11.5	7.4	6.0
Race/ethnicity, %
White, non-Hispanic	83.1	86.0	87.6	84.7	83.9	84.1
Region of residence, %
Northeast	23.9	24.3	17.3	22.7	24.2	22.2
South	22.3	29.6	12.2	21.7	22.7	24,6
Midwest	18.8	21.2	31.1	22.0	19.5	21.0
West	15.5	13.2	16.5	15.1	17.3	15.9
Canada	19.5	11.7	22.9	18.5	16.4	16.3
Urban, %	69.5	76.4	59.4	69.1	69.2	69.9
BMI (kg/m^2), mean	29.9	29.4	30.5	29.9	28.8	27.7
Physical activity (MET-hrs)
Moderate Physical Activity, mean	19.9	16.6	20.2	19.1	17.9	16.8
Vigorous Physical Activity, mean	17.7	20.1	17.8	18.2	17.0	16.7
Smoking, %
Never Smoker	69.1	74.4	66.9	69.5	76.1	74.8
Former Smoker	16.8	14.8	13.0	15.5	14.6	14.5
Current Occasional Smoker	3.4	3.6	8.4	4.5	4.1	3.8
Current Regular Smoker	10.7	7.3	11.7	10.6	5.2	7.0
Married, %	86.8	92.0	82.9	87.3	89.6	90.3
Nulliparous, %	71.0	70.0	71.3	70.6	64.8	66.8
Last method of contraception was hormonal %	43.0	43.1	36.7	41.6	35.0	38.6
Intercourse frequency (times/week), %
<1	23.7	17.4	26.7	22.9	21.6	20.7
≥4	19.2	14.1	18.9	18.2	15.2	16.3
Doing something to improve chances of conception	80.9	79.0	74.2	79.3	74.5	76.5
Mental health diagnosis, %
Anxiety	33.0	43.8	35.3	36.0	30.9	22.5
Depression	33.7	34.5	31.8	33.1	31.8	23.9
Hay Fever Diagnosis, %	23.2	31.7	30.4	26.0	16.7	6.7

Notes: ^aAll characteristics except for age are standardized to baseline age of cohort. ^bThese percentages refer to the distribution of medication use among participants who reported being ever diagnosed with asthma. For example, 19.7% of participants who report being ever diagnosed with asthma took medication when having symptoms.

Table 2 Asthma Medication Use and Fecundability Among 8286 Female Pregnancy Planners

Exposure	Number of Pregnancies	Number of Cycles	Unadjusted FR (95% CI)	Adjusted^a FR (95% CI)	Adjusted^b FR (95% CI)
No asthma diagnosis, no medication use	4015	25,860	Ref	Ref	Ref
Ever diagnosed with asthma, no medication use	515	3474	0.97 (0.89, 1.05)	0.98 (0.91–1.07)	1.00 (0.91, 1.09)
Asthma medication use^c
Any	269	1779	0.98 (0.87–1.10)	1.02 (0.91–1.14)	1.02 (0.91–1.15)
Frequency
When having symptoms	157	1004	1.05 (0.90, 1.22)	1.09 (0.94, 1.27)	1.08 (0.93, 1.25)
Daily	60	351	1.01 (0.79, 1.29)	1.02 (0.80, 1.30)	1.01 (0.79, 1.29)
Daily and more when having symptoms	51	407	0.80 (0.62, 1.05)	0.86 (0.65, 1.12)	0.89 (0.68, 1.16)
Medication class^d
Inhaled combination corticosteroid and long-acting beta agonists	54	433	0.82 (0.62–1.08)	0.86 (0.66–1.11)	0.86 (0.66–1.12)
Inhaled Corticosteroid	45	323	0.91 (0.60–1.37)	0.93 (0.64–1.36)	0.90 (0.62–1.33)
Any inhaled corticosteroid	86	620	0.88 (0.69–1.12)	0.92 (0.72–1.16)	0.91 (0.72–1.16)
Leukotriene inhibitors	46	295	1.01 (0.68–1.49)	1.02 (0.72–1.44)	1.03 (0.73–1.46)
Short-acting beta agonists	247	1627	0.99 (0.88–1.11)	1.03 (0.91–1.16)	1.04 (0.93–1.17)
Treatment escalation group^e
Group 1 (short-acting beta agonist only)	162	1055	1.00 (0.83–1.19)	1.03 (0.87–1.22)	1.04 (0.88–1.24)
Group 2 (maintenance only)^f	25	148	0.94 (0.63–1.42)	0.95 (0.62–1.46)	0.93 (0.60–1.42)
Group 3 (inhaled corticosteroid and short-acting beta agonist)	41	215	1.14 (0.77–1.69)	1.24 (0.84–1.83)	1.29 (0.85–1.97)
Group 4 (other maintenance combinations and short-acting beta agonist)	44	368	0.81 (0.57–1.35)	0.85 (0.62–1.17)	0.85 (0.62–1.18)
Age at first asthma diagnosis
<5 years	82	495	1.06 (0.87–1.30)	1.05 (0.86–1.29)	1.04 (0.85–1.26)
5–17 years	355	2240	1.00 (0.90–1.11)	1.00 (0.91–1.11)	1.01 (0.92–1.12)
≥18 years	153	1187	0.85 (0.73–0.99)	0.90 (0.77–1.04)	0.89 (0.77–1.04)

Notes: ^aage, BMI, race, education, income ^bage, BMI, race, education, income, smoking status, hormonal birth control as last form of birth control, intercourse frequency, doing something to improve chances of getting pregnant, physical activity, region of residence, anxiety diagnosis, depression diagnosis, hay fever diagnosis, health insurance, primary care provider visits, MDI score, PSS score ^cself-reported use in the last four weeks, at baseline ^dnot mutually exclusive ^emutually exclusive ^fmaintenance medications include inhaled corticosteroids, inhaled combination corticosteroid and long-acting beta-agonists, and leukotriene inhibitors.