Pregnancy-Nausea and vomiting

Pregnancy related nausea and vomiting can be a challenging situation. From excluding serious causes to prescribing an anti-emetic safely, this chart can help the clinician in tackling the situation in a structured fashion.The aetiology of NV in Pregnancy ( NVP ) is mentioned followed by a section on differential diagnosis and assessment. Pharmacological management is discussed in detail and the choice of anti-emetics are cited clearly. You can guide the patient to look at support groups as  Pregnancy Sickness Support, Mothers at risk and UKTIS. Role of complementary therapy in the management of pregnancy related NV is also discussed.

Background- Typically starts between 4th-7th weeks Peaks at approx 9 th week 75-80 % of pregnant ♀ experience this
♦ varying intensity
♦ various length of time
 Symptoms subside by 20th week in 90 % cases
 About 0.3 % – 3.6 % develop hyperemesis gravidarum ( HG )

HG is severe form of NVP- requires hospital admission

♦ 5 % prepregnancy weight loss
♦ dehydration
♦ electrolyte imbalance

HG can be life threatening if not treated promptly and can ↑ the risk of fetal loss , preterm birth , LBW

Previous HG- advice risk of recurrence in future pregnancies
 NVP can have sig impact on physical and emotional health- impact can be comparable to those undergoing cancer chemotherapy.Only diagnose NVP
 in 1st trimester→ when other causes have been excluded

Commonly called morning sickness but not confined to morning

Aetiology-Fetoprotective ( embryoprotection ) Genetic Biochemical Immunological Biosocial

Rising levels of hCG- ie conditions with ↑↑ levels of hCG as
♦ trophoblastic dis
♦ multiple pregnancy

are associated with ↑ severity of NVP
 Ongoing work to study interaction of TSH suppression and hCG
○ hCG is the thyroid stimulator of pregnancy and biochemical hyperthyroidism is seen commonly in HG Link between hCG and estradiol Female gender of the fetus associated with ↑ severe HG Role of H Pylori. Pathogenesis poorly understood , possibly multifactorial 

Differential diagnosis-Gastrointestinal conditions
○ Gastroenteritis
○ Gastroparesis
○ Achalasia
○ Biliary tract disease
○ Hepatitis
○ Intestinal obstruction
○ Peptic ulcer dis
○ Pancreatitis
○ Appendicitis
 Genitourinary tract conditions
○ Pyelonephritis
○ Uraemia
○ Ovarian torsion
○ Kidney stones
○ Degenerating uterine leimyoma
 Metabolic conditions
○ Diabetic ketoacidosis
○ Porphyria
○ Addison’s disease
○ Hyperthyroidism
○ Hyperparathyroidism Neurological disorders
○ Pseudomotor cerebri
○ Vestibular lesions
○ Migraine headaches
○ Tumours of CNS
○ Lymphocytic hypophysitis
 Miscellaneous conditions
○ Drug toxicity or intolerance
○ Psychologic condition
 Pregnancy related conditions
○ Acute fatty liver of pregnancy
○ Pre-eclampsia

history- Previous h/o NVP / HG Qantify severity
♦ nausea
♦ vomiting
♦ hypersalivation
♦ spitting
♦ loss of weight
♦ inability to tolerate food and fluids
♦ effect on quality of life
 History to exculde other causes
♦ abdominal pain
♦ urinary symptoms
♦ infection
♦ drug history
♦ chronic H pylori infection

Examination-Temp Pulse BP Saturation Resp rate Abdominal examination Weight Signs of dehydration Signs of muscle wasting Other exam as guided by hx

Investigations-Urine dipstick 
○ quantify ketonuria as + 1 ketones or > MSU Us and Es FBC Bl glucose US scan Refractory cases or h/o previous admissions
○ TFTs
○ LFTs
○ Calcium and phsophate
○ Amylase
○ ABG. Biochemical changes in NVP/ HG

Low serum urea
↑ Haematocrit
Ketonuria with met hypochloraemic alkalosis
Abnormal TSH ↑ Transaminases in HG
Slightly raised bil and amylase

Management-Women who have vomiting but are not dehydrated can be managed in community with anti-emetics , support , reassurance , oral hydration and dietary advice Ginger
○ mild to moderate NVP
○ three systemic reviews have assessed effectiveness
○ no ↑ ed risk of malformations
○ 250 mg by mouth 4 times a day
○ acupressure
○ acupuncture- Nei Guan P6 pressure point
 3 fingers breadth proximal to the wrist between
 tendons of palmaris longus and FCRadialis
safe and may improve NVP
 Hypnosis- not recommended Mindfullness based cognitive therapy Little evidence for dietary changes

Avoid Iron in 1st trimester-supplemental iron not required while maintain Folic acid 
( if it make PNV worse )

First line
○ Antihistamines ( H1 receptor antagonists ) eg
♦ Cyclizine 50 mg tds po
♦ Promethazine 12.5 to 25 mg q6-8h po
♦ Cinnarizine
♦ Doxylamine
♦ Dimenhydrinate

○ Phenothiazines for eg 
♦ Prochloroperazine ( Stemetil ) 5-10 mg orally tds
♦ Chlorpromazine 10 to 25 mg q6-8h 
♦ Perhenazine
 Second line
○ Metoclopramide → risk of extrapyramidal SEs
 use short term
 max 30 mg in 24 hrs
○ Ondansetron ( data controversial )- can be used as an adjunctive therapy for severe NVP when other antiemetic combinations hae failed
 Corticosteroids- avoid during 1st trimester and restricted to refractory HG Diazepam → not recommended for NVP or HG Pyridoxine ( vitamin B6 ) Cochrane review – limited data

Input may be required 
in severe NPV/ HG from-midwives , nurses , dietitians , pharmacists , endocrinolgists ,
 nutritionists , gastroenterologists and psychiatrists

Antacids- Ranitidine / PPIs- consider using to treat acid reflux or bloating 
( can exacerbate PNV )