Antenatal Care

Antenatal Care First visit When 6 to 8 weeks pregnant Full medical and family history Examination of circumstances that may be relevant to pregnancy Model of care: Person who is lead maternity care Where will maternity care be received and by whom Planned schedule or number of antenatal visits Where birth will be given Most women have uncomplicated pregnancies so their visits between 8 to 10. May be more in some women E.g. those with complicated or high-risk pregnancies Exam General appearance Height and weight Vitals Upper limb Head Neck Chest Abdomen Lower limb Breast examination Breast lumps can become more difficult as gestation advances -> breast cancer rapidly progresses -> EARLY DIAGNSOIS IS IMPORTANT Detailed gynaecological exam Inspect of the external genital E.g. FGM Bimanual palpation of the of the uterus and adnexa Speculum examination of the vagina and cervix if is pap smear or cervical swaps are indicated Findings in vaginismus view is important as has implications of pregnancy, labour and the birth itself. FBE or FBC Important for: Excluding anaemia Screening for thalassaemia and thrombocytopenia Risk in baby if the dad is a carrier Thalassaemia is screened for using low MCV Blood group and antibody screen D negative Require further screening at weeks 28 and birth Prophylaxis with passive anti-D Women who are D positive may have antibodies against other red cell antigens E.g. c, E, K, Fya Microbiology screening Rubella antibodies If not immunised -> early immunisation Varicella antibodies Syphilis Hepatitis B, hepatitis C and HIV Midstream urine for microscopy, culture and sensitivity. 6% of women have asymptomatic bacteriuria in first antenatal visit -> 1/3 develop pyelonephritis is bacteriuria is untreated. Results given on next visit Cervical screening When a woman is pregnancy treatment for high grade cervical intraepithelial neoplasia will need to be deferred until puerperium As treatment may cause excess bleeding or precipitate miscarriage Screening for genetic conditions such as down syndrome Amniocentesis or CVS Additional investigations Hb electrophoresis If there is low MCV? Beta thalassemia Sickle cell Serum ferritin If there is an increased risk of iron deficiency e.g. vegetarian In centres of high prevalence this might become a routine test Chlamydia swabs For at risk women Vitamin D Required for those with dark skin and/or reduced sunlight exposure during pregnancy Significance for newborn is yet to be determined. Supplementation is recommended if levels are less than 50 nmol/L Thyroid function Subclinical hypothyroidism -> consequences for pregnancy General advice Nutrition Listeria sepsis Avoid soft cheese where is it made from unpasteurised milk, soft serve ice cream, raw fish (e.g. sushi, smoked salmon, oysters), cold meats, salad bars and pate Proper food preparing techniques Ensure meat is cooked thoroughly esp. poultry Take care with pre-pared foods and those made with mayonnaise or crustaceans Healthy diet and avoid excess nutritional intake Regula weighing at each visit reduces chance of excessive weight gain Iron, iodine and calcium Encourage non-vegetarians to eat red meat Vegetarians -> oral iron if ferritin is low. Salt should be used sparingly but of iodised variety. Multiple supplementation Periconceptual folic acid supplementation -> prevents neural defects Decreases adverse pregnancy outcomes including placental abruption and preeclampsia. Exercise Light to moderate level is recommended Strenuous exertion should be avoided Linked to smaller birth weights Maternal hypoxia during excursion -> bad for placenta gas exchange Avoid alcohol Smoking Increased risk of miscarriage and perinatal death Illicit drugs Medications Ones that can be continued: Paracetamol Metoclopramide Common penicillins e.g. amoxycillin Common asthma medications e.g. salbutamol and/or corticosteroid inhalers Mental health medications can be usually continused -? Risk vs benefit Inform on laxatives that are safe on pregnancy as constipation is a common complication in pregnancy Sexual intercourse No evidence of harm including preterm birth But pregnancy duration at term is on average a few days shorter in sexually active women Avoid within a week of any bleeding in pregnancy Prohibited after rupture of gestational membranes Employment Most are fatigue in late pregnancy and choose to go in maternity leave from 34 weeks Physical work -> raise blood pressure -> increased risk of pre-term birth May consider not working Travel Safe in second trimester Avoid after 36 weeks First and third carry the most risk of miscarriage and of preterm birth Avoid long flights CVT Difficult to receive care in emergencies e.g. antepartum haemorrhage and preterm labour Vaccinations Influenza vaccine is safe and important Killed vaccines e.g. influenza is safe Live vaccines are contraindicated Infections CMV and toxoplasmosis Risk can be reduced by sensitive handwashing before food prep and after exposure to risk prone events e.g. gardening (toxoplasmosis) or children at childcare (CMV) Antenatal Care Visits for Low-Risk Pregnancies Weeks 10 to 12: book list, dating U/S, bloods and psychosocial screen Week 16 to 19: review results and morphology scan Week 20 to 27: BP, urine, foetal growth and GDM screen Week 28: FBC, antibody screen, Anti-D if Rh negative and EDPs Week 29 to 34: growth, birth plan, breast feeding, repeat Anti-D (wk 34) Week 35 to 37: fetal presentation, GBS swab and newborn prep Week 30 to 40: labour discussion, foetal movements, BP Week 41 and over: post-dates management Additional risk-based tests: Hep C, STIs, Thyroid. Role of the 18-week morphology scan/mid trimester scan Fetal anatomy Head to toe evaluation: Brain, spine, heart, kidneys, limbs, face and abdominal wall defects Anomality detection Major congenital issues Neural tube defects, cardiac malformations, abdominal wall defects Placental location Assess for placenta previa or abnormal placental implantation Fetal growth Biometric parameters Head circumference, femur length, abdominal circumference, fetal sieze These are used to estimate gestational age and growth trajectory. Amniotic fluid volume Polyhydramnios or polyhydramnios. Cervical length Risk of preterm by evaluating cervical integrity Checks for multiple gestations Sex determination -> not the main purpose though Midtrimester scan Between 18 and 22 weeks Congenital abnormalities: Neural tube defects, cardiac anomalies, limb abnormalities and abdominal wall defects Placental assessment Location and morphology Screen for placenta previa or abnormal implantation Amniotic fluid volume Polyhydramnios or oligohydramnios Indicators of fetal wellbeing from ultrasound examination. Parameter What is assessed Importance Presence Confirms viability Fetal heart activity Rate Abnormal rhythms -> arrythmias or hypoxia Rhythm Fetal movements Spontaneous limb and body Intact nervous system and oxygenation movement Fetal tone At least one episode of active If absent suspected IUGR or hypoxia movement Fetal movements breathing Diaphragmatic motion Seen after 20 weeks and is part of biophysical profile Amniotic fluid volume Measured via AFL or deepest Oligohydramnios -> placental insufficiency pocket Polyhydramnios -> fetal anomalies Growth parameters HC, AC, FL and BPD Serial measurements assess growth trajectory and effect IUGR or macrosomia Position Placenta previa Placental location and Grade appearance Abruption risk Abnormalities Signs of insufficiency Resistance index Elevated resistance -> placental insufficiency or fetal compromise Umbilical artery doppler S/D ratio Assesses for fetal anaemia or hypoxia MCA Peak systolic velocity Reduced resistance -> brain sparing effect Used in high-risk pregnancies to assess cardiac function and fetal compromise Ductus venous doppler Flow pattern Score out or 8 or 10 Biophysical profile Combines U/S and CTG Includes movement, tone, amniotic fluid index and non-stress test. Importance fetal abnormalities which are screening for by ultrasound examination at varying stages during pregnancy. Timing First Trimester (11–13+6 weeks) Scan Type Key Abnormalities Screened Importance - Enables early risk - Chromosomal anomalies (e.g. Down stratification Nuchal translucency syndrome, Trisomy 18/13) via NT thickness - May prompt further scan (part of - Major structural anomalies (e.g. testing (e.g. NIPT, combined screening) anencephaly, cystic hygroma) CVS) - Early cardiac defects - Supports informed decision-making Second Morphology scan Trimester (midtrimester (18–22 weeks) anomaly scan) Third Trimester (28+ weeks) - Neural tube defects (e.g. spina bifida) - Cardiac anomalies - Renal and GI tract malformations - Limb and facial abnormalities - Abdominal wall defects (e.g. gastroschisis, omphalocele) - Placental location and amniotic fluid volume - Intrauterine growth restriction (IUGR) - Late-onset anomalies Growth and wellbeing - Placental insufficiency scan (if indicated) - Oligohydramnios/polyhydramnios - Doppler abnormalities (e.g. umbilical artery, MCA) - Most comprehensive structural assessment - Guides referral to fetal medicine, genetic counselling - Allows planning for delivery and postnatal care - Monitors fetal wellbeing in high-risk pregnancies - Informs timing and mode of delivery - Detects evolving pathology not seen earlier