Placental pathology in HIV infection at term: a comparison with HIV-uninfected women

Abstract

Objectives: To describe and correlate placental characteristics from pregnancies in HIV-infected and HIV-negative women with maternal and infant clinical and immunological data.

Methods: Prospective descriptive study of placentas from term, uncomplicated vaginal births in a cohort of HIV-infected (n = 120) and HIV-negative (n = 103) women in Cape Town, South Africa. Microscopic and macroscopic features were used to determine pathological cluster diagnoses. The majority of HIV-infected women received some form of drug treatment for the prevention of vertical transmission of HIV. Data were analysed using logistic regression.

Results: HIV-infected women were older (median [IQR] 27.4 years [24-31] vs. 25.8 [23-30]), more likely to be multiparous (81.7% vs. 71.8%) and had lower CD4 counts (median [IQR] 323.5 cells/ml [235-442] vs. 467 [370-656]). There were no differences in gestational age at first antenatal visit or at delivery. The proportion of specimens with placental lesions was similar in both groups (39.2% vs. 44.7%). Half of all samples were below the tenth percentile expected-weight-for-gestation regardless of HIV status. This was unaffected by adjustment for confounding variables. Maternal vascular malperfusion (MVM) was more frequent in HIV infection (24.2% vs. 12.6%; P = 0.028), an association which strengthened after adjustment (aOR 2.90 [95% confidence interval 1.11-7.57]). Otherwise the frequency of individual diagnoses did not differ between the groups on multivariate analysis.

Conclusions: In this cohort of term, uncomplicated pregnant women, few differences were observed between the HIV-infected and uninfected groups apart from MVM. This lesion may underlie the development of hypertensive disorders of pregnancy, which have been observed at higher rates in some HIV-infected women on ART.

Keywords: HIV infection; bajo peso placentario; embarazo a término; faible poids placentaire; grossesse à terme; histopathologie; histopathology; histopatología; infección por VIH; infection VIH; low placental weight; mala perfusión placentaria; maternal vascular malperfusion; mauvaise vascularisation maternelle; placenta; term pregnancy.