What could cause bleeding after sex and a week after my period?

Postcoital and Intermenstrual Bleeding: Diagnostic Approach

You need an immediate gynecologic evaluation with pregnancy testing, cervical inspection, and transvaginal ultrasound to exclude serious pathology—postcoital bleeding and intermenstrual spotting can signal cervical lesions, polyps, infections, or endometrial abnormalities that require prompt diagnosis. 1

Immediate First Steps

Pregnancy testing is mandatory as your first action, even if you believe pregnancy is unlikely, as this fundamentally changes the entire diagnostic pathway. 1 The timing of bleeding one week after your period does not exclude pregnancy, particularly if you had unprotected intercourse during or after menstruation. 2

Critical Diagnostic Workup

Cervical Evaluation

• Speculum examination is essential to directly visualize the cervix for lesions, polyps, erosions, cervicitis, or other structural abnormalities that commonly cause postcoital bleeding. 1, 3
• Cervical pathology (including cervical cancer, polyps, and inflammation) is a leading cause of bleeding after intercourse and must be excluded. 2, 3

Transvaginal Ultrasound

• Pelvic ultrasound should be performed to evaluate for structural uterine pathology including endometrial polyps, submucosal fibroids, adenomyosis, and to assess endometrial thickness. 1, 4
• Ultrasound can identify polyps in the endocervical canal that may not be visible on speculum examination alone. 2

Infection Screening

• STI testing for chlamydia and gonorrhea is indicated, as cervicitis is a common cause of irregular bleeding and postcoital spotting. 1, 5
• Endometritis and pelvic inflammatory disease can present with intermenstrual bleeding. 3

Endometrial Assessment

• Endometrial sampling should be strongly considered given the pattern of irregular bleeding, particularly if you are over 35 years old or have risk factors for endometrial pathology. 1, 4
• Women with recurrent irregular bleeding patterns require endometrial evaluation to exclude hyperplasia or malignancy. 4

Additional Laboratory Testing

• Complete blood count to assess for anemia from chronic or recurrent spotting. 1
• Thyroid function testing should be considered, as thyroid dysfunction commonly causes abnormal uterine bleeding patterns. 4, 3
• Coagulation studies may be warranted if you have a personal or family history of bleeding disorders or if bleeding is heavy. 4, 3

When Specialist Referral Is Required

Immediate gynecology referral is necessary if:

• Persistent unexplained bleeding continues after initial evaluation. 1
• Abnormal endometrial thickness or masses are identified on ultrasound. 1
• Cervical lesions are visualized that require biopsy or treatment. 1
• Any suspicion of malignancy based on examination or imaging findings. 2, 3

Common Pitfalls to Avoid

Do not assume this is "normal spotting" without excluding structural and infectious causes first. 1, 5 Postcoital bleeding specifically warrants cervical evaluation as it can be the presenting symptom of cervical pathology. 2, 3

Do not delay evaluation based on age alone—while younger women more commonly have benign causes, serious pathology can occur at any reproductive age. 4, 3

If you are using hormonal contraception (particularly progestin-only methods), irregular bleeding is common during the first 3-6 months, but new-onset bleeding after a period of regular cycles still requires evaluation to exclude pregnancy, infection, and structural pathology. 5