Intestinal parasitic infections in pregnant women in Sao Tome & Principe: are there adverse birth outcomes?

Background Up to 70% pregnant women in Africa have an intestinal parasitic infection (IPI), but their adverse birth outcomes (ABOs) remain unclear. Sao Tome & Principe (STP) is an IPI high-endemic country but there is a paucity of data. This study aimed to identify an association between ABOs -maternal anaemia, prematurity (PTB), low-birth-weight (LBW) and stillbirths- and IPI in pregnant women. Methods A hospital-based cross-sectional study was conducted among pregnant women admitted for delivery. ANC pregnancy cards were checked for coproparasitological results, treatments, and haemoglobin levels. A structured questionnaire was administered to assess sociodemographic factors. Newborn records were used for ABOs. Pregnant with a monoparasitic-IPI (n=145) and polyparastic-IPI (n=25) were compared to noninfected-group (n=151) for ABOs. IPI-subgroups: helminthiasis (n=162), schistosomiasis (n=11) and amebiasis (n=7), were each compared to the noninfected-group. Chi-square and Fisher´s exact tests were used to identify associations between ABOs and IPI in pregnant women at p- value<0.05. Results A total of 361 pregnant women with a mean age of 26.96 (SD: 7.00) were included. From the 210 positive coproparasitological exams, 90.9% had Ascaris lumbricoides , followed by 13.8% Trichuris trichiura , 5.2% Schistosoma intercalatum and 3.3.% Entamoeba histolytica . Anaemia in monoparasitic-IPIs (145) was 46.7% compared to 38.7% in noninfected-group. ABOs in monoparasitic-IPI-women were 6.2% PTB, 11% LBW and 3.4% stillbirths, without any statistically significant difference (p=0.175, p=0.07, p=0.275), respectively, when compared with noninfected-women. ABOs for polyparasitic-IPI compared with noninfected-group also showed no statistically significant difference. A statistically significant difference was also not found for the subgroup’s helminthiasis, schistosomiasis and amebiasis when compared with noninfected pregnant women. Conclusion The lack of ABOs in our study can be related to the predominant type – Ascaris lumbricoides – a low pathogenicity parasite. This study is a useful starting point for health policy development for pregnant women in a high-IPI endemic country.