Definitions:
- First Trimester = 0-12 wks Second = 12-28 wks Third = 28-40wks
- Term = 37-42
- Active Labour: regular contractions result in cervical change / descent of the fetus (presenting part)
- Gravity = # pregnancies of any gestation
- T = # of term infants P = # premature A = # of abortions L = # of living Children
1 In a patient who is considering pregnancy:
a) Identify risk factors for complications.
b) Recommend appropriate changes (e.g., folic acid intake, smoking cessation, medication changes).
Preconception Counselling
- GA 3-8 wk is a critical period of organogenesis
- PMH – optimize medical illness
Supplements
- Folic acid supplement 8-12 wk preconception until end of T1
- 0.4-1mg/d
- 5mg/d if previous NTD, anti-epileptic meds, DM or BMI >35
- Iron supplement & prenatal vitamins
Risk Modification:
- Lifestyle: balanced nutrition & physical fitness
- Meds – ? teratogenic
- Infection screening: rubella, HBsAg, VDRL, Pap smear, G/C, HIV
- Genetic testing – appropriate for high risk group
- Social: EtOH, smoking, drug use, domestic violence (ask every women about abuse)
Counselling:
Nutrition
- Ca 1200-1500mg/d + Vit D 1000 u – 3-4 servings of milk daily
- Daily caloric increase – 100 cal/d in 1st, 300 cal/d in 2nd, 450 cal/d in 3rd
- Wt gain 6.8-18.2 kg (depends on pre-pregnancy weight)
- Advise all women of childbearing age to supplement diet with 0.4mg/day (5mg/d if high risk) Folic acid for the first 12 wk of(materna has 1 mg/day)
- decreases indicence of NTD
- Food rich in folic acid: spinach, lentils, chick peas, asparagus, brocoli, peas, brussels sprouts, corn and oranges
- Iron supplement (0.8mg/d in T1, 4-5mg/d in T2, >6mg/d in T3) if anemic, prenatal vitamins
- Req amount > normal body stores & typical intake – need supplement iron
- daily multivitamin not necessary in 2nd trimester (unless not consuming an adequate diet)
- Essential fatty acids – vegetable oils, margarines, peanuts, fatty fish
- supports fetal neural and visual development
Caffeine – diuretic & stimulant
- 1-2 cups/d are safe during pregnancy (SOGC)
- <200mg/d is not thought to contribute to miscarriage or preterm birth / relationship to IUGR ? (AOGC)
Food Borne illnesses
- Avoidance of cats/litter/rodents (toxoplasmosis), soft cheeses/deli meats, smoked salmon, pates (listeria), raw fish / eggs / poultry, unpasteurized dairy products
- 0.5ppm of mercury in fish is not considered harmful – limit consumption of top predator fish, eg shark, swordfish, tuna (one meal / month)
Social Hx:
- EtOH – no amount is safe in pregnancy
- encourage abstinence
- ↑ SA, stillbirth, congenital anomalies (FAS)
- smoking – reduce or quit
- ↑ low birth wt, placenta previa / abruption, SA, preterm labour, stillbirth
- Drug cessation
- Cocaine ↑ microcephaly, growth retardation, prematurity, placenta abruption
- Inquire about safety, domestic violence, genetic disease
- Exercise
- C/I: ROM, Preterm labour, HTN, Incompetent Cervic, IUGR, multiple gestations (>3), placenta previa >28wk GA, 2nd/3rd trimester bleeding, twin pregnancy >28wk GA
- uncontrolled DM1 / thyroid dz, anemia (hgb <100) other CVS / Resp / endo disorders
- Work – strenuous work / extended hours and shift work – ↑ low birth weight, prematurity, SA
- Travel – not harmful, air travel ok in T2, cutoff GA36-38wk (depending on the airline)
- Intercourse – continue except
- at risk for abortion, preterm labour, placenta previa
- breast stimulation may induce uterine activity
PmHX
- heart conditions, past uterine/cervical procedures, STI’s
- maternal age, birth defects, multiple gestation
Med:
- Review meds/OTC meds. – motherrisk.org
- Discuss cessation of current form of birth control
Family Hx:
- Genetic screening of high risk groups (tay-sachs, sickle cell, thalessemia)
2 In a female or male patient who is sexually active, who is considering sexual activity, or who has the potential to conceive or engender a pregnancy, use available encounters to educate about fertility.
Discuss STI’s, appropriate forms of contraception, and emergency contraception.
Dx of pregnancy
Symptoms:
- amenorrhea – LMP, N/V, breast tenderness, u frequency, fatigue
- Nagele’s rule = 1st day of LMP + 7days – 3 months.
Signs:
- Goodell’s sign – softening of the cervix (4-6wk)
- Chadwick’s sign – bluish discolouration of the cervix / vagina (6wk)
- Hegar’s sign – softening of the cervical isthmus (6-8wk)
- Uterine enlargment / breast engorgement
3 In a patient with suspected or confirmed pregnancy, establish the desirability of the pregnancy.
Confirm pregnancy with urine/serum bHCG &/or US
- Serum bHCG – positive 9 d post-conception
- doubles Q1-2 d, peak 8-10wk, fall to a plateau until delivery
- Less than expected
- ectopic, abortion, inaccurate dates
- Higher than expected
- Multiple gestation, molar pregnancy, T21, inaccurate dates
- Urine bHCG – positive 28d after LMP
- US
- Transvaginal
- 5wk – gestational sac (bHCG >1500), 6 wk – fetal pole, 7-8 wk – fetal heart tones
- Transabdominal
- 6-8wk – intrauterine pregnancy visible (bHCG – >6500)
- Transvaginal
4 In a patient presenting with a confirmed pregnancy for the first encounter:
a) Assess maternal risk factors (medical and social). – objective 1
b) Establish accurate dates.
c) Advise the patient about ongoing care.
Repeat visits q4weeks until 28, q2weeks until 36, qweekly until delivery.
>2-3mo preconception |
|
<12 wk | Routine Dating U/S for all pregnant women (SOGC 2014):
U/S also for
|
≥12 wk | routine FHR with handheld Doppler |
>8 wk |
Visit 1: Fill out prenatal forms, refer if needed
Visit 2: Physical Exam + Pap Smear, if not done in past 6mo & >21yo, vaginal swab for BV, cervical Cx for G/C |
UTI | UTI and asymptomaic bacteriuria (midstream Cx >105 )Tx: Macrobid 100mg po bid x 7 days – avoid at labour and delivery due to hemolytic anemia
Repeat U Cx in 1-2 wk after Tx |
11-13wk + 6d | CVS prn, 1% risk of loss, earlier dx than aminocentesis1st trimester integrated serum screen – Part 1 – T18, 21 & U/S NTSIPS vs. IPS (SIPS + NT): Depending on the age(risk) of your patients and their desire for screening after informed consent. Amniocentisis may be offered after age 40 with no prior screening (http://www.bcprenatalscreening.ca/page202.htm)Indications for Nuchal Translucency U/S:
|
16 wk | TA cut-off in most provinces |
15-17wk | Amniocentesis – routinely offered to women >40yo & >35yo with multiple gestation; 0.5% risk of loss |
15-20wk + 6d(16-18wk) | Part 2 or Quad screen (if no part 1) – T18, 21, ONTDs |
18-24wk | Routine u/s for dates (inaccurate +/-2wk) /anomalies |
≥20wk | SFH measurement routinely |
24-26 wk |
|
28wk | Repeat CBC / Hg (screen with anemia in T3) often with GDM screening (24-26wk)Re-screen STI/HIV if high risk
|
30-32wk | u/s to r/o IUGR in women w/initial wt >90kg or BMI >30 |
28-36 wk | Repeat HIV, G/C, syphilis testing if at risk |
35-37 wk | GBS swab (36wk) – vaginal + rectal (valid for 5 wk), send result to delivery suit unless + GBS bacteriuria during the current pregnancy or prev infant with GBS dz |
38+ wk | Consider Cervical exam at prenatal visitOffer sweeping of membranes to prevent posterm getation |
41-42 wk | Induction to prevent posterm gestation vs expectant (req fetal monitoring with NST & AFT bi-weekly |
Delivery |
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Postpartum | GDM – a 75g OGTT at 6-12 wk pp to screen for persistent DM or impaired glucose tolerance |
5 In pregnant patients:
a) Identify those at high risk (e.g., teens, domestic violence victims, single parents, drug abusers, impoverished women).
b) Refer these high-risk patients to appropriate resources throughout the antepartum and postpartum periods.
OB consult if
- posible C/S: VBAC, malpresentation, multiple gestation
- antepartum care: HTN, PTL/PPROM, failure to progress/descend, induction / augmentation if high risk
- PP care: 3/4 degree tear, retained placenta
Refer to social worker and local mental health unit
6 In at-risk pregnant patients (e.g., women with human immunodeficiency virus infection, intravenous drug users, and diabetic or epileptic women), modify antenatal care appropriately.
Diabetes:
- Insulin for type 1, or type II uncontrolled by diet alone. Oral hypoglycemics (especially glyburide) are controversial
- Diet usually adequate for GDM. Multi-disciplinary approach with diabetes educators, dieticians, and maternity care provider.
HIV:
- Fetus at risk of IUGR, pre-term labor or PROM.
- Rescreen for HIV at 28 – 36 wk GA if high risk
- May deliver vaginally. Combined retroviral for antepartum decrease risk of transmission to <1%.
- Discuss risk of transmission with breast feeding.
Epileptics:
- For planning a pregnancy, switch to the safest effective anti-convulsant at lowest dose(avoid valproic acid). If already pregnant, continue with same anti-convulsant meds.
- Folate supplementation 5mg/d.
- Vit K supplementation in final month with enzyme inducing meds.
- Monitor drug levels.
IVDU:
- Arrange supports, encourage cessation,
- surveilance for HIV/Hep B/C during pregnancy – repeat screening in T3
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