Trimethoprim Use prior to Pregnancy and the Risk of Congenital Malformation: A Register-Based Nationwide Cohort Study
Table 1
Study population characteristics.
Use of trimethoprim in the 12-week period prior to pregnancy
No use of trimethoprim in the 12-week period prior to pregnancy
Age (year)
28.5
29.7
Parity (mean)
1.80
1.85
Household income—number (%)
<$50,000
76 (19)
80,899 (16)
$50,000–$100,000
194 (48)
241,907 (46)
$100,000–$150,000
110 (27)
150,163 (29)
>$150,000
22 (5)
48,240 (9)
Education—number (%)
Low
168 (42)
182,072 (35)
Medium
123 (31)
165,132 (32)
Long
98 (24)
149,324 (29)
No information available
10 (2)
13,333 (3)
Comorbidityb—number (%)
Teratogenic infectious diseasesc
1a (0.3)
133 (0.0)
Folate deficiency
0 (0)
39 (0.0)
Myasthenia gravis
0 (0)
38 (0.0)
Virilizing tumors
0 (0)
84 (0.0)
Diabetes Mellitus
4 (1)
6258 (1)
Alcoholism
0 (0)
111 (0.0)
Amniocentesis
1a (0.3)
5381 (1.0)
Sjogren’s syndrome
0 (0)
38 (0.0)
HIV/AIDS
0 (0)
60 (0.0)
Pneumocystis carinii pneumonia
0 (0)
2 (0.0)
Previous organ transplantation
1a (0.0)
49 (0.0)
Use of folic acid—number (%)
9 (2)
4296 (1)
aNone had offspring with a congenital malformation.
bAll information on comorbidity were based on diagnoses from the National Hospital Register. cSyphilis, toxoplasmosis, rubella virus, varicella virus, parvovirus B-19, cytomegalovirus, herpes simplex viruses 1 and 2, and Venezuelan equine encephalitis virus.