Obstetrics – Dr. ’Abeer – Lecture 2 - Abdominal pain in pregnancy Physiology Pain is produced in different tissues and it is protective mechanism for the body. It occurs whenever any tissues being damaged, and it cause the individual to react to remove the stimulus. Three types of stimuli excite pain receptors: Mechanical, Thermal, Chemical. It has been suggested that pain is chemically mediated and that stimuli that provoke it have in common the ability to liberate a chemical agents that stimulate nerve endings. This chemical agent might be a kinin or histamine, both of which cause pain on local injection. Abdominal Pain In Pregnancy Abdominal pain in pregnancy is often due to a benign cause but may be very difficult to diagnose with certainty. Unless a benign cause can be established with certainty in the absence of maternal or fetal distress then urgent hospital referral is usually indicated. Causes of abdominal pain in pregnancy 1. Pregnancy related Early pregnancy: 1. ectopic pregnancy 2. miscarriage Later pregnancy: 1. 2. 3. 4. 5.

labour (term or preterm). placental abruption. uterine rupture. acute Polyhydramnios choioamniotitis, usually precipitated by pre-term premature rupture of membranes

2. Gynecological causes: 1. 2. 3. 4.

Ovarian cysts or tumours, including rupture, haemorrhage or torsion Red degeneration of a fibroid Uterine torsion Round ligament pain: more common at the beginning and end of pregnancy, more common in multips and pain is aggravated by movement.

3. Non-gynecological causes a. Abdominal wall, especially symphysis pubis and ligament strains. b. Gastrointestinal causes: 1. Constipation 2. Appendicitis: affects 1 in 1500 pregnancies, less common than in non-pregnant women. Diagnosis is complicated by change in position of appendix which is carried high and to the right and there may not be localization of pain. Nausea, vomiting, fever together with any right-sided abdominal pain are suspicious of this. Leucocytosis is suggestive. Appendicitis is not diagnosed in 1 in 5 cases in pregnant women until the appendix has ruptured causing peritonitis, which can cause premature labour or abortion. 3. Perforated peptic ulcer, gastritis 4. Bowel obstruction, e.g. adhesions, volvulus

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5. Gallstones, cholecystitis: cholecystitis is relatively common in pregnancy occurring usually late, 90% of cases have gallstones most of which can be visualized under ultrasound. Conventionally cholecystectomy is only necessary in complicated cases such as obstruction, as can cause 15% perinatal mortality. In advanced pregnancy, cholecystostomy may be is possible. ERCP and endoscopic retrograde sphincterotomy are possible if exposure to radiation is minimized. In early to middle of second trimester, laparoscopic cholecystostomy carries few problems. Most patients only require symptomatic relief. 6. Pancreatitis 7. Hepatic disorders: e.g. pre-eclampsia, acute fatty liver of pregnancy, HELLP syndrome c. Renal system, e.g. cystitis, Pyelonephritis and stones d. Other uncommon causes include 1. 2. 3. 4.

sickle cell crisis. malaria. porphyria and diabetic ketoacidosis.

e. Psychological: diagnosis by exclusion and must be very careful not to miss a physical cause for the abdominal pain.

Investigations 1. Fetal monitoring 2. Urine analysis, MSU: infection, proteinuria in pre-eclampsia 3. Full blood count: raised white cell count suggestive of infection, although the white cell count is normally slightly raised in pregnancy 4. Liver function tests 5. Ultrasound: may demonstrate ectopic pregnancy, abruption, miscarriage 6. Laparoscopy to confirm ectopic pregnancy Management A thorough assessment of the wellbeing of the mother and fetus, as well as the possible underlying cause is required. Treatment of cause; urgent hospital referral if uncertain cause, and/or maternal or fetal distress.

Diagnosis of abdominal pain in later pregnancy and after childbirth Palpable contractions Blood-stained mucus discharge (show) or watery discharge before 37 weeks Cervical dilatation and effacement Light a vaginal bleeding Possible preterm labour a Light bleeding takes longer than 5 minutes for a clean pad or cloth to be soaked.

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• Palpable contractions • Blood-stained mucus discharge (show) or watery discharge at or after 37 weeks • Cervical dilatation and effacement • Light vaginal bleeding Possible term labour

• Intermittent or constant abdominal pain • Bleeding after 22 weeks gestation (may be retained in the uterus) • Shock • Tense/tender uterus • Decreased/absent fetal movements • Fetal distress or absent fetal heart sounds. Abruptio placentae

Severe abdominal pain (may decrease after rupture) • Bleeding (intra-abdominal and/or vaginal) • Shock • Abdominal distension/ free fluid • Abnormal uterine contour • Tender abdomen • Easily palpable fetal parts • Absent fetal movements and fetal heart sounds • Rapid maternal pulse Possible Ruptured uterus

• Abdominal pain • Foul-smelling watery vaginal discharge after 22 weeks gestation • Fever/chills • History of loss of fluid • Tender uterus • Rapid fetal heart rate • Light vaginal bleeding Possible Amnionitis

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• Abdominal pain • Dysuria • Increased frequency and urgency of urination • Retropubic/suprapubic pain Possible Cystitis

• Dysuria • Abdominal pain • Spiking fever/chills • Increased frequency and urgency of urination • Retropubic/suprapubic pain • Loin pain/tenderness • Tenderness in rib cage • Anorexia• Nausea/vomiting Acute Pyelonephritis

• Lower abdominal pain • Low-grade fever • Rebound tenderness • Abdominal distension • Anorexia • Nausea/vomiting • Paralytic ileus • Increased white blood cells • No mass in lower abdomen • Site of pain higher than expected Possible Appendicitis

• Lower abdominal pain • Fever/chills • Purulent, foul-smelling lochia • Tender uterus • Light vaginal bleeding • Shock Endometritis

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• Lower abdominal pain and distension • Persistent spiking fever/ chills • Tender uterus • Poor response to antibiotics • Swelling in adnexa or pouch of Douglas • Pus obtained upon culdocentesis Pelvic abscess

• Lower abdominal pain • Low-grade fever/chills • Absent bowel sounds • Rebound tenderness • Abdominal distension • Anorexia • Nausea/vomiting • Shock Peritonitis

• Abdominal pain • Adnexal mass on vaginal examination • Palpable, tender discrete mass in lower abdomen • Light vaginal bleeding Ovarian cyst

• Abdominal pain • Light bleeding • Closed cervix • Uterus slightly larger than normal • Uterus softer than normal • Fainting • Tender adnexal mass • Amenorrhoea • Cervical motion tenderness Ectopic pregnancy

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