Table 2. Concentration of invasion- modulating factors in pooled serum from uninfected and P. falciparum infected women at enrolment.

Analyte	reported effect on trophoblast invasion	mean (SD) conc. in uninfected women	mean (SD) conc. in P.f infected women	P value
IGF-I	+	180 (2)	114 (1)	0.07
IGF-II	+	1964 (82)	1470 (60)	0.1
IL-8	+	163 (3)	87 (15)	0.09
hCG	–	23 (1)	27 (1)	0.1
IL-10	–	5.2 (0.1)	17.4 (2.0)	0.08
IL-1β	–	not detected	2.2 (0.9)	–
TNFα	–	not detected	1.6 (0.4)	–
IL-6	+/−	4.2 (0.8)	4.4 (0.3)	–
IL-12p70	unreported	not detected	1.9 (0.9)	–

Note: Mean concentrations (and SD) of invasion stimulatory factors (IGF-I, IGF-II, and IL-8) were lower in pooled serum from women with P. falciparum infection compared to match uninfected controls. In the same pooled serum samples, factors that inhibit trophoblast invasion (hCG, IL-10) were higher in infected women than in uninfected women. IGF- Insulin like growth factor, IL- interleukin, TNF tumor necrosis factor, hCG human chorionic gonadotrophin. (+) indicates known previously reported trophoblast invasion-promoting effects [46], [47], [48], [49], [50], known trophoblast invasion inhibitory effects are indicated by (−) [48], [49], [51], [52], reports of both inhibitory and promoting effects are indicated by (+/−) [53], and (unreported) indicates an absence of previous reports on trophoblast invasion. All analyte concentrations in pooled serum were measured once and are expressed as pg/ml, except hCG (IU/ml). IGF-I, IGF-II and hCG were measured in triplicate (analyzed using the Mann-Whitney test), and all cytokines were measured in duplicate (analyzed using unpaired t test with Welch’s correction).