Risk Factors for Preterm Birth among HIV-Infected Tanzanian Women: A Prospective Study

Table 1

Study population characteristics, .

Characteristic	(%) or median [IQR]
Preterm births (<37 wks)	227 (24%)
Very preterm births (<34 wks)	87 (9%)
Gestational age at enrollment (weeks)	21 18, 23
Gestational age at birth (weeks)	39 37, 41
Sociodemographic
Maternal age at conception (years)	25 22, 29
<20	96 (10%)
No partner	103 (11%)
Illiterate	70 (8%)
Nutrition and Anthropometric
Plasma vitamin A (g/dL)	23.4 17.9, 30.2
<20	246 (34%)
Plasma vitamin E (µmol/L)	9.6 8.0, 11.4
<9.7	368 (51%)
Selenium (mg/mL)	0.12 0.11, 0.14
<0.11	218 (26.49%)
0.11-0.12	148 (17.98%)
0.12–0.14	250 (30.38%)
≥0.14	207 (25.15%)
Hemoglobin (g/dL)	9.5 8.4, 10.5
<7.0	59 (6%)
7.0–8.4	188 (21%)
8.5–10.9	508 (56%)
≥11.0	112 (12%)
Mid-upper arm circumference (cm)	25.0 23.5, 27.5
≤23.5	225 (26%)
23.6–25.0	203 (24%)
25.1–27.5	220 (26%)
>27.5	203 (24%)
Weight gain (g per week)	255 116, 380
≤0	112 (12%)
1–119	126 (14%)
≥120	689 (74%)
Height (cm)	156 152, 160
<150	90 (10%)
Infections
Malaria	176 (19%)
Hookworm	92 (12%)
Entamoeba coli	69 (9%)
Ascaris lumbricoides	43 (6%)
Cryptosporidium parvum	34 (4%)
Entamoeba histolytica	15 (2%)
Strongyloides stercoralis	14 (2%)
Trichuris trichiura	9 (1%)
Giardia lamblia	4 (1%)
Enterobius	0 (0%)
Isospora	0 (0%)
Microsporidia	0 (0%)
Taenia	0 (0%)
Trichomoniasis	232 (25%)
Syphilis	44 (6%)
Vaginal candidiasis	41 (6%)
Gonorrhea	9 (1%)
HIV/AIDS
WHO HIV disease stage ≥ 2	189 (20%)
CD4 count (cells/mm^3)	402 275, 530
<200	112 (13%)
Viral load (copies/mL)	47819 11626, 146135
≥50,000	193 (50%)
Other clinical variables
Twins	22 (2%)
Diastolic blood pressure (mmHg)	70 60, 70
Systolic blood pressure (mmHg)	110 100, 110
Prehypertension or hypertension^b	259 (28%)

AIQR: interquartile range.
^aNot all numbers add up to 927 due to missing data.
^bSystolic blood pressure > 120 mmHg or diastolic blood pressure > 80 mmHg.