The short explanation
There are two things to think about: pregnancy and infections. For pregnancy, emergency contraception works best when used as soon as possible after sex. Emergency pills are available from pharmacists and doctors and are effective for several days, though they work better the sooner they are used. A copper IUD inserted by a doctor within about five days is the most effective option. For infections, the risk depends on your partner's history. If there is any chance of HIV, ask a doctor urgently about PEP, which must be started within 72 hours. STI tests can be done after about two weeks, with blood tests later. A pregnancy test is recommended about three weeks after the sex if your period has not come.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Condoms can break if they are old, stored in heat, used without enough lubricant, or with oil-based lubricants.
- Using condoms correctly every time, along with another contraceptive method, reduces risk.
- Government hospitals and family planning clinics offer emergency contraception and STI testing confidentially.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This answer cannot tell your personal risk. A doctor or pharmacist can advise on emergency contraception and testing.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Which emergency contraception option suits me?
- Do I need PEP for HIV?
- When should I test for pregnancy and STIs?
- How can we prevent condoms from breaking?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Get help the same day
- Get care the same day for emergency contraception, and to discuss PEP if there is any HIV risk.
Book an appointment soon
- Do a pregnancy test about three weeks after the sex if your period has not come.
Raise it at a routine appointment
- Book STI testing about two weeks after the sex.
Sources
The evidence this explanation is built on.
- Sexually transmitted infections MedlinePlus (NIH)
- Sexually transmitted infections (STIs) World Health Organization
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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