TABLE 2.
Distribution of children with small head circumference growth in strata defined by pregnancy characteristics and exposures during pregnancy
| Exposures and characteristics | Head circumference Z-scorea | n | ||
|---|---|---|---|---|
| <−2 | ≥−2 to <−1 | |||
| Smoking prepregnancyb | Yes | 8 | 23 | 359 |
| No | 10 | 21 | 1012 | |
| Smoking during pregnancyb | Yes | 8 | 25 | 205 |
| No | 10 | 21 | 1166 | |
| Years since last pregnancy | <1 | 7 | 23 | 163 |
| 1–2 | 8 | 17 | 235 | |
| ≥2 | 11 | 23 | 417 | |
| Conception assistance | Yes | 7 | 17 | 271 |
| No | 10 | 23 | 1096 | |
| Vaginal bleeding | ||||
| ≤12 wkb | Yes | 8 | 21 | 522 |
| No | 10 | 23 | 844 | |
| >12 wkb | Yes | 7 | 21 | 392 |
| No | 11 | 22 | 974 | |
| Illnesses this pregnancy | ||||
| Feverb | Yes | 10 | 25 | 83 |
| No | 10 | 22 | 1282 | |
| Vaginal/cervical infection | Yes | 7 | 24 | 187 |
| No | 10 | 22 | 1179 | |
| UTIb | Yes | 10 | 25 | 219 |
| No | 10 | 21 | 1147 | |
| Medications | ||||
| Anyb | Yes | 10 | 22 | 159 |
| No | 6 | 23 | 1206 | |
| Aspirinb | Yes | 8 | 26 | 80 |
| No | 10 | 22 | 1280 | |
| NSAIDb | Yes | 4 | 27 | 99 |
| No | 10 | 21 | 1260 | |
| Acetaminophenb | Yes | 11 | 21 | 697 |
| No | 8 | 22 | 662 | |
| Antibioticb | Yes | 10 | 24 | 430 |
| No | 9 | 21 | 930 | |
| Maximum no. of infants | 138 | 317 | 1445 | |
These are row percents.
NSAID, nonsteroidal antiinflammatory drug; UTI, urinary tract infection.
a
External standard is Oxford, United Kingdom, dataset;11
b
infants may be in >1 category.
McElrath. Factors associated with small head circumference at birth among ELGAN. Am J Obstet Gynecol 2010.