Sex and first-trimester bleeding: what to know

Pregnancy increases blood flow around the cervix, so light spotting after penetration can occur when this tissue is easily irritated. Bleeding can also happen for reasons unrelated to sex, including changes in the pregnancy or an infection. A small amount does not tell you by itself whether the pregnancy is continuing normally.

One serious cause is an ectopic pregnancy, in which a pregnancy develops outside the womb. It may cause one-sided lower abdominal pain, shoulder-tip pain, dizziness or fainting alongside bleeding. Read more about ectopic pregnancy if these symptoms are present.

Stop penetration while you are bleeding and use a pad so you can observe the amount and colour. Note when it began, whether clots or tissue appeared, and whether cramps or pain accompanied it. Contact your maternity team or clinician for individual advice, even when spotting is light.

Avoid inserting anything into the vagina until a clinician has advised you. Do not drive yourself if you feel faint or unwell. A clinician may ask about your pregnancy dates, examine you, and arrange tests or an ultrasound depending on your symptoms.

Seek emergency care for heavy bleeding, severe or worsening abdominal pain, one-sided pain, shoulder-tip pain, fainting, marked dizziness, fever, or feeling acutely unwell. These warning signs need assessment because bleeding can accompany complications that cannot be diagnosed safely at home.

Ask what amount of bleeding should prompt a return visit, whether you should avoid sex for now, which pain relief is suitable in pregnancy, and whether you need an examination, blood test or ultrasound.