Bleeding after sex in the third trimester

Pregnancy increases blood flow to the cervix, so contact during sex can make its delicate surface bleed. However, late-pregnancy bleeding can also come from the placenta or the start of labour, and the source cannot be confirmed from colour or amount alone.

A small smear may follow friction against the vagina or cervix, particularly when tissues are sensitive. Cervical inflammation or infection can also cause contact bleeding. Blood mixed with mucus may occur as the cervix changes near labour, but bleeding can also signal a placental problem.

Note whether the blood is pink, red or brown, whether it is increasing, and whether you have pain, tightening, fluid leakage or a change in your baby's movements. These details help the maternity team decide where and how quickly to assess you.

Stop sex, use a sanitary pad rather than a tampon, and contact your maternity unit or obstetric clinician promptly. Tell them how much blood you saw, when it began, its colour, and any accompanying symptoms. Avoid further vaginal penetration until a clinician says it is appropriate.

Your assessment may include questions about placenta position, an abdominal examination, monitoring of the baby's heartbeat, or a careful examination to locate the bleeding. Bring your pregnancy records if you are asked to attend.

Seek emergency maternity care now if bleeding is heavy or continuing, or if it occurs with severe abdominal pain, regular contractions, dizziness, fainting, fluid leakage, or reduced fetal movement. Do not drive yourself if you feel faint or unwell.

Even without those warning signs, report any third-trimester bleeding promptly. If your blood group is Rh negative, mention this when you call because the clinical team may need to consider additional care.

Ask whether you need examination or fetal monitoring, whether the placenta's location is known, and when sex can safely resume. You can also ask which changes in bleeding, pain, contractions, fluid loss or movement should prompt an immediate return.