text: does the oral contraceptive has side effect on fetus? more at first trimester or second is same symptoms (side effect as nausea , headech,) that of ocp and of pregnancy extensive research has shown that ocs do not have a measurable or appreciative efect upon developing fetuses. that doesn't mean its ironclad, so if you think you mihgt be pregnant stop taking hte pill, use another form of contarception and get a test. this will remove all doubt and guilt in most cases. today's ocs have so much less hormone in them that it is unlikely that they are terratogenic.