Increased pregnancy weight gain in women with latent toxoplasmosis and RhD-positivity protection against this effect.
OBJECTIVE
RhD-positive subjects are protected against toxoplasmosis-associated impairment of psychomotor performance. Here we searched for RhD-positivity-associated maternal protection against the effects of toxoplasmosis.


METHODS
In the present retrospective cohort study, we analysed data from 785 (139 RhD-negative) Toxoplasma-free and 194 (27 RhD-negative) Toxoplasma-infected pregnant women. We searched for effects of toxoplasmosis and Rhd-phenotype on maternal weight before pregnancy, pregnancy weight gain, fetal ultrasound data (biparietal diameter, abdominal circumference, femur length) and on birth length and weight.


RESULTS
At pregnancy week 16, the RhD-negative mothers with toxoplasmosis gained more weight than others (P < 0.001). The difference of about 1600 g remained approximately constant from pregnancy week 16 until the end of pregnancy. Neither toxoplasmosis nor RhD phenotype had any effect on fetal bioparameter data or birth length and weight.


CONCLUSIONS
The most parsimonious explanation for the observed data is that the RhD-positive phenotype might protect infected subjects against a broad spectrum of detrimental effects of latent toxoplasmosis, including excessive gestational weight gain.
Kaňková
S
S
Department of Parasitology, Faculty of Science, Charles University in Prague, Viničná 7, CZ-12844 Prague 2, Czech Republic.
Sulc
J
J
Flegr
J
J
D000328:Adult; D000818:Animals; D001724:Birth Weight; D001835:Body Weight; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D015597:Pregnancy Complications, Parasitic / Q000097:blood / Q000469:parasitology / Q000503:physiopathology*; D012204:Rh-Hr Blood-Group System / Q000097:blood* / Q000276:immunology; D014122:Toxoplasma; D014123:Toxoplasmosis / Q000097:blood / Q000469:parasitology / Q000503:physiopathology*; D016216:Ultrasonography, Prenatal; D015430:Weight Gain; D055815:Young Adult
D012204:Rh-Hr Blood-Group System; C026410:Rho(D) antigen