Prenatal Care


8-10 weeks- Typically first visit.  Remember:  All residents need to have an attending examine all First Obs for size, and all Ob pts need to be checked out with the attending before the leave the clinic.
·        History:
                   Family or personal history of congenital diseases?
                   Prior baby with trisomy or neural tube defect?
                   Med problems (asthma, DM, HTN, psych, gyn infxns)?
                   Surgeries?  Blood transfusion?
                   Past OB history
                   History of domestic violence?
·        Counseling:
                   No tobacco, Etoh, caffeine?, illicit drugs
                   Medications
                   Cat litter & raw meat – toxoplasmosis
                   Hot tubs & getting overheated in exercise
                   Diet – increase caloric intake by 300 calories a day
Prenatal vitamins – 800 mcg folate/day recommended.  If
Prior NTD, 4mg/day.   If DM or Epilepsy, 1mg/day.
                   HIV test
                   Encourage moderate exercise
                   Offer flu vaccinations to women in their 2nd and 3rd trimesters
                   Offer Hep B vaccinations to at-risk women
·        Exam:  General PE, Pap with GC/chlamydia, Sizing
·        Labs:
                   Blood type & Rh, RPR, Hep B, CBC, Rubella, HIV
                   Urine C&S
                   Chlamydia and Gonorrhea
 
10-12 weeks
·        Fetal heart tones w/ Doppler.  US if unable to obtain by 12wks.
 
16-20 weeks
·        Genetic counseling
·        Quadruple test:  MSAFP, HCG, inhibin and estriol.  Recommended between 16-18 weeks EGA, can do between 15-20 wks.
o       Neural tube defects—increased MSAFP.  If at increased risk (h/o previous NTD, IDDM, valproic acid), offer amnio.
o       Down Syndrome—increased HCG, decreased MSAFP and estriol.  Many false positives.
o       Trisomy 18—decrease in all markers.
·        Amniocentesis—Offer to all women who will be 35 by the time of delivery or women at increased risk.
·        Fetal movement by 20 weeks.  US the pt if not reported.
 
24-28 weeks
·        1 hour glucose tolerance test (O’Sullivan or 1hr GTT)
If positive (>140), obtain 3 hour GTT.
                   Fasting > 105 (if 105 or above refer to HROB)
                   1 hour > 190        2 hour > 165      3 hour > 145
          If 2 or 3 elevated refer to HROB (High Risk OB clinic)
·        Repeat CBC
·        Rhogam—given in clinic.  If you have only one documentation of Rh status, repeat Rh and screen prior to administering.
·        Tubal ligation?  Consent must be signed four weeks before expected delivery.  OB doc generally has them call the OB clinic when they deliver to schedule this post-pardum.  All tubals done during C-sections have to go through a special approval process.
·        Preterm labor precautions.
 
32-34 weeks
·        Discuss options for analgesia in labor
·        Circumcision?
·        Birth control—give information on options, make sure that consent is signed (if they are planning tubal ligation).
·        Reinforce preterm labor precautions
·        Fetal movement, fetal kick counts
·        Assess fetal position with Leopold’s
 
34-36 weeks
·        GBS screening done
·        Fetal position
 
39-40 weeks
·        Answer questions about delivery
·        Discuss possibility of post dates and protocol for induction
·        Evaluate cervix
>40 weeks
·        Patients should be referred to HROB clinic at 41 2/7 weeks to evaluate for induction.
·        Patients >41 weeks need twice weekly NST & weekly AFI.
 
Ongoing Screening
·        Blood pressure
o       PIH—HTN > 20 weeks gestation.
o       Preeclampsia—SBP >140 or rise of >30 mmHg systolic or DBP > 90 or rise > 15 mmHg diastolic.  Elevated BPs must be present >=2 separate occasions 6 hrs apart. 
o       Severe preeclampsia—SBP > 160 or DBP > 110, proteinuria > 5g/24 hours (3+ to 4+), cerebral or visual changes, epigastric pain, thrombocytopenia, olguria < 400ml/24h, pulmonary edema, HELLP
o       Severe chronic HTN—risk of abruption & preeclampsia
·        Weight
o       Normal wt gain is 25-35 pounds for normal wt woman
o       Discourage wt loss in pregnancy
o       Weight gain of >3lbs/week is concerning
·        Urine protein
·        Fundal height—after 20 weeks, should correspond to week of gestation.  Watch for >3 cm difference.
·        Edema—dependent edema is normal
Edema of face, greater than 5 pound weight gain in a week, pitting edema after 12 hours of rest are concerning
 
Dating a Pregnancy
·        Dating is crucial.  To date use LMP, sizing exam, doptones at 10-12 weeks, fetoscope at 20 weeks (U/S if needed)
·        Refer for U/S if pt presents > 20 weeks for care, if there is large discrepancy between size and “sure” dates, or if one of the above milestones is not met.
·        If you have reliable sources of dating, do not change the dates based on a late U/S if the original due date is within the margin of error of the U/S.
          1st trimester U/S can be off by 1 week
          2nd trimester U/S can be off by 2 weeks
          3rd trimester U/S can be off by 3 weeks.
          If LMP is sure and U/S is within margin of error, use LMP
·        If more than one U/S has been obtained, dating is based on the earliest U/S.
·        Uterine Size / Dates
o       7wk = egg                                         
o       10wk = orange
o       12wk = grapefruit, above symphysis
o       20wk = fundus at umbilicus
o       20-36wk = fundal ht equals gestational age within 2 weeks. 
o       Doppler at 10-12wks                         
o       Fetoscope at 18-20wks
High Risk OB Clinic
The following is a list of patients who must be referred to HROB.  Please see HROB Policy and Procedure or Cindy Nicolay (our head clinic RN) for more details.
·        U/S for dating pts who present > 20 weeks or who have abnormal AFP
·        PTL, HTN, Prior C-section, Breech or transverse, Postdates, Pre-existing maternal diabetes, GDM, Anemia, History of stillbirth, Genital herpes-primary outbreak in third trimester, Multiple pregnancy, DVT and heparin therapy, Collagen vascular disease, Renal insufficiency, Seizure disorder, Active thyroid disease, History of incompetent cervix, Drug abuse/dependence, and inadequate fundal growth (no change in weight for 2 consecutive visits, 3 cm difference between fundal height and date)
 
Treating Common Infections in Pregnancy
·        UTI – 7 day regimen, needs Test of Cure
          Nitrofurantoin SR (Macrobid)
          TMP/SXT (Septra/Bactrim)-possible teratogenicity 1st trimester; possible neonatal hyperbilirubinemia near term
          Cephalexin (Keflex)
          Avoid amoxicillin – high E. coli resistance (unless you have C/S)
·        Bacterial Vaginosis – Needs Test of Cure (TOC) in 1 month
          BV linked to increased risk for PTL & endometritis
          Metronidazole (Flagyl) 250 mg po tid x 7 days
          Can use metronidazole 0.75% gel (5g) intravaginally x 5 QHS
·        Trichomonas—metronidazole 2gm single dose.  Treat partner.
·        Vulvovaginal candidiasis—topical azole creams only, for 7d
·        Chlamydia – needs TOC in 1 month.  Treat partner.
          Azithromycin 1g single dose or
          Erythromycin 500 mg po qid x 7days or
          Amoxicillin 500 mg po tid x 7 days
          Screen high risk women again in third trimester.
                   Do not use:  tetracyclines or fluorquinolones