Ovulation Pain

Ovulation pain is cyclical pain felt in the lower abdomen or pelvis around the time of ovulation, usually mid-cycle (day 10 to 16 of a 28 day cycle). It affects about 1 in 5 ovulating women at least occasionally.

• Mechanisms: stretching of the ovarian capsule by the maturing follicle; irritation of the peritoneum by follicular fluid and blood at ovulation; prostaglandin induced tubal and uterine contractions.
• Self limiting, benign; the diagnosis depends on exclusion of other pelvic pathology.
• It can be useful as a fertility awareness sign (the fertile window surrounds the pain).
• Persistent or severe ovulation pain can occur with endometriosis, ovarian cysts, pelvic adhesions, or hormonal stimulation (fertility drugs).

• Unilateral lower abdominal or pelvic pain, dull ache or sharp twinge, lasting a few minutes to 1 to 2 days, mid-cycle; may switch sides cycle to cycle.
• Possible light spotting, increased clear cervical mucus, mild nausea, breast tenderness.
• No fever, no discharge, no significant tenderness or guarding on examination.
• Red flags: severe or worsening pain, vomiting, fainting, shoulder tip pain, fever, missed period (ectopic pregnancy), heavy bleeding, abnormal discharge, pain lasting more than 3 days or non-cyclical, pain with intercourse (deep), a pelvic mass, pain on fertility drugs with abdominal distension and rapid weight gain (ovarian hyperstimulation syndrome).

• Clinical diagnosis from a menstrual diary linking pain to mid-cycle; ovulation can be confirmed by home luteinising hormone kits or mid-luteal progesterone (day 21 of a 28 day cycle; level above 30 nmol/L indicates ovulation).
• Pregnancy test whenever the period is delayed or the pain atypical.
• Pelvic ultrasound if severe, recurrent or persistent pain, to exclude cysts, endometrioma, torsion or free fluid.
• Chlamydia and gonorrhoea tests if discharge, risk or tenderness.
• Differential: appendicitis, ruptured corpus luteum cyst, ovarian torsion, ectopic pregnancy, pelvic inflammatory disease, endometriosis, urinary tract infection, constipation, irritable bowel syndrome.

• Reassurance and education.
• Analgesia taken at pain onset: paracetamol 1 g orally every 6 hours (maximum 4 g per day) or ibuprofen 400 mg orally every 6 to 8 hours with food; heat pack to the lower abdomen; rest.
• Persistent troublesome pain: suppress ovulation with a combined oral contraceptive pill (ethinylestradiol 20 to 35 micrograms), a progestogen only pill that inhibits ovulation (desogestrel 75 micrograms daily), the etonogestrel implant, or depot medroxyprogesterone acetate 150 mg intramuscularly every 12 weeks, reviewed at 3 months.
• Women wishing to conceive: avoid hormonal suppression; the pain can help time intercourse.
• Advise urgent review for severe pain, fainting, vomiting, fever or a positive pregnancy test.
• Refer for gynaecological ultrasound or laparoscopy if pain persists beyond 3 cycles of treatment or is progressive.