Adverse foetal outcome in specific IgM positive Chlamydia trachomatis infection in pregnancy

Abstract

A study was undertaken to determine the adverse foetal outcome in antichlamydial IgM positive asymptomatic pregnant females. An indirect immunoperoxidase assay was done to detect IgM in 78 apparently normal asymptomatic pregnant women during the third trimester and follow up was done till delivery to study the effect of chlamydial infection on foetal outcome. A total of 28 (35.9%) women were positive for antichlamydial IgM while only 3.33 per cent asymptomatic non-pregnant normal women (controls) were positive. 28.7 per cent IgM positive mothers delivered low birth weight (LBW) babies (P less than 0.05), 9.7 per cent had premature labour (PTL) and 4.7 per cent had intrauterine death (IUD). The findings are significant as none of the IgM negative mothers had PTL and IUD and only 2.6 per cent had LBW babies. PIP: Health workers screened 108 18-30 year old asymptomatic pregnant women (78 pregnant women and 30 nonpregnant women) who attended Queen Mary's Hospital in Lucknow, India between March 1989-February 1990 for Chlamydia trachomatis infection (specific IgM antibodies) to determine if it adversely affects the fetus. None of the women had 3 children. 35.9% (21) of pregnant women tested positive for IgM antibodies against chlamydia compared to 3.3% of nonpregnant women. Health workers were only able to follow 60 pregnant women to delivery. 28.7% of IgM positive mothers gave birth to LBW infants while only 2.6% of IgM negative mothers did (p.05). Indeed 85.7% of LBW infants were born to mothers with chlamydia infection compared to 14.3% born to mothers free of chlamydia infection in (p.05). The average birth weight for infants born to IgM positive mothers stood at 2.21 kg whereas it stood at 2.74 kg for infants born to IgM negative mothers (p.001). Moreover 9.7% of all IgM positive cases experienced premature labor and 4.7% gave birth to still born infant while none of the IgM negative cases experienced either 1 of these 2 adverse outcomes. These differences were significant. These results demonstrate that IgM seropositivity against chlamydia induces premature labor (probably due to rupture of membranes), slows intrauterine fetal growth, and results in fetal death.