Induced abortion as cancer risk factor: a review of epidemiological evidence.

Abstract

The issue of the oncological implications of induced abortion is reviewed based on the limited literature available. 2 conflicting interpretations emerge in understanding the potential risk factors. One view is that any pregnancy interrupted or full term is protective or neutral. The other view is that sudden termination creates hormonal blows to the endocrine immunological neurological and other processes and there is incomplete growth of breast tissues. The statistical results have not been strong enough to determine the nature of the impact and are frequently biased by the attitude of the researcher. There is an apparent lack of information from populations like the USSR with a high induced abortion rate. Questions such as whether the effects during the reproductive years of induced abortion are the same before between or after live births and whether gestational age and type of termination technique influences cancer risk. Cervical and breast cancer relationships to induced abortion have been studied with conflicting results while the very few studies of ovarian and endometrial cancers indicate little or no effect from induced abortion. There is some evidence to suggest that there is a mildly significant relationship controlling for other reproductive factors between induced abortion before 1st full term pregnancy and breast cancers. In the USSR regional variation in induced abortion accounts more for cervical cancer than fertility rates.