Thanks for your query.
If the pregnancy
test is positive, then it means your wife is pregnant.
It means that she conceived sometime before the episode you described.
RIght now, you have to consult an obstetrician if you want termination of pregnancy.
She will have to examine your wife and decide the weeks of gestation and confirm that pregnancy is intra uterine.
After that, she would prescribe appropriate medicines or advise surgical abortion
A follow up visit to confirm completion of abortion is required.
Also, please switch over to a reliable birth control method, as emergency contraceptive pill
is not regular or reliable method.