14.3 Pregnancy and Postpartum Primary Care

Prenatal care is FNP scope in many settings. The exam will not punish you for knowing first-trimester labs, folic acid, vaccines, gestational-diabetes timing, and RhoGAM. It will punish you for keeping an ectopic pregnancy, heavy bleeding, or preeclampsia in a 20-minute slot. Teach the essentials you own and the red flags you transfer.

Confirmation, dating, and the prenatal laboratory panel

Confirm pregnancy with urine or serum hCG. Then date the pregnancy. Naegele’s rule (first day of the last menstrual period plus 7 days minus 3 months) is a start when cycles were regular. A first-trimester crown-rump length is the most accurate dating tool and is what you use when LMP and ultrasound disagree by the usual threshold. Document an intrauterine pregnancy: gestational sac, yolk sac, then fetal pole and cardiac activity. Know the discriminatory zone conceptually — when serum hCG is high enough that a transvaginal ultrasound should show an intrauterine sac (commonly discussed around 1,500–3,500 mIU/mL, assay-dependent). An hCG above that range and an empty uterus is ectopic until proven otherwise, not “too early, come back in a month.”

Order the prenatal panel at the first obstetric visit:

Add varicella IgG if history is uncertain, hemoglobin electrophoresis when ancestry or MCV suggests it, and early glucose testing when obesity, prior GDM, or known hyperglycemia raises risk. Aneuploidy screening (NIPT or a serum screen) is offered, not forced. The FNP’s job is informed consent and a pathway to genetics or obstetrics when the result is abnormal — not improvising a risk score from memory.

Vitamins, vaccines, and danger signs

Every prenatal vitamin must include folic acid at least 400 mcg daily, started ideally one month before conception. If she has a prior neural-tube defect, the dose is 4 mg (4,000 mcg) daily, not a regular over-the-counter prenatal. Iron, B12, and vitamin D are individualized from the CBC and diet. Do not sell megadose vitamin A.

Vaccines in pregnancy:

• Inactivated influenza — any trimester, every influenza season
• Tdap — each pregnancy, preferably at 27–36 weeks, to push pertussis antibody to the newborn
• COVID-19 — follow current ACIP pregnancy recommendations; do not withhold because of pregnancy alone
• RSV vaccine — seasonal, in the late-third-trimester window ACIP currently names, when she will deliver into RSV season
• No live vaccines — MMR, varicella, and live-attenuated influenza stay out until postpartum

Give RhoGAM counseling in the same visit you review vaccines so Rh-negative patients do not fall off the list.

Danger signs leave the clinic. Teach them out loud and write them down:

• Vaginal bleeding or leaking fluid
• Severe headache, visual change, right-upper-quadrant pain, or sudden swelling (preeclampsia)
• Decreased fetal movement after viability
• Dysuria with fever, flank pain, or contractions
• Regular preterm contractions, or a severe asthma or glucose crisis

Preeclampsia is new hypertension after 20 weeks plus proteinuria or end-organ signs. It is obstetric and often emergency-department disease, not an office hydrochlorothiazide start. Preterm labor, placenta previa with bleeding, and cholestasis of pregnancy also transfer.

Gestational diabetes, RhoGAM, and when the FNP transfers

Screen for gestational diabetes at 24–28 weeks in pregnancies not already known to have diabetes. Two protocols are acceptable; know that both exist. The one-step 75-g OGTT uses fasting, 1-hour, and 2-hour cutoffs (commonly fasting ≥92, 1-hour ≥180, 2-hour ≥153 mg/dL — one abnormal value diagnoses). The two-step path is a nonfasting 50-g glucose challenge, then a 100-g diagnostic OGTT if the screen is high. Early screening belongs in people with prior GDM, obesity, or known impaired glucose. Abnormal results mean nutrition referral, home glucose logs, and obstetric or diabetes comanagement when insulin or metformin enters the plan. Delivery timing is not a solo FNP decision once GDM is on medication.

RhoGAM (anti-D immune globulin) is for Rh-negative, antibody-negative patients. Give it at about 28 weeks, within 72 hours after delivery if the newborn is Rh-positive, and after sensitizing events — miscarriage, ectopic pregnancy, chorionic villus sampling, amniocentesis, abdominal trauma, and abruption. A missed 28-week dose is a preventable alloimmunization. Do not give RhoGAM to someone who is already alloimmunized; those titers belong in maternal-fetal medicine.

Transfer or comanage when the pregnancy is no longer ordinary: multiples, placenta previa, pregestational diabetes on insulin, significant cardiac or renal disease, HIV, suspected fetal anomaly, cervical insufficiency, or any hypertensive disease of pregnancy. State and employer protocols differ; the exam wants the clinical trigger, not your county’s contract.

Postpartum care, ectopic pregnancy, and miscarriage

The postpartum visit is not a Pap smear and a smile. Screen for depression (Edinburgh Postnatal Depression Scale is the usual tool) and ask about thoughts of self-harm and harm to the infant. Review bleeding (lochia should taper; soaking a pad an hour or passing large clots is hemorrhage until proven otherwise) and the cesarean or perineal wound. Start or confirm contraception before she leaves — fertility can return before the first menses, including in people who breastfeed. Immediate postpartum IUDs and implants are appropriate. Combined hormonal contraception is MEC category 4 in the first 21 days because of VTE risk; wait longer (to 42 days) when additional VTE risk factors exist. Progestin-only methods can start earlier. Exclusive breastfeeding, amenorrhea, and infant age under 6 months is lactational amenorrhea — reasonably effective, not a promise.

After preeclampsia, blood pressure can stay high or rebound in the first 1–2 weeks and can present as postpartum preeclampsia up to about 6 weeks. Arrange close blood-pressure follow-up, do not stop surveillance at hospital discharge, and treat severe-range pressures as an emergency. These patients also carry a long-term cardiovascular risk that belongs on the problem list. Postpartum thyroiditis can swing through thyrotoxicosis then hypothyroidism in the first year; check TSH when fatigue, palpitations, or depression do not match the story. Continue breastfeeding through most mastitis treatment (dicloxacillin or cephalexin are usual) rather than “pump and dump” by default.

Ectopic pregnancy is unilateral pelvic pain, spotting, and a positive pregnancy test, with an empty uterus or an adnexal mass — and sometimes with shoulder pain or hemodynamic collapse from rupture. Unstable patients go to the emergency department by EMS. Stable but suspected ectopics go to obstetrics the same day for serial hCG and ultrasound, not a “repeat urine pregnancy test next week” plan. Methotrexate, when used, is an obstetric protocol with follow-up hCG, not an FNP hallway prescription.

Miscarriage ranges from threatened (closed cervix, bleeding, viable intrauterine pregnancy) to inevitable, incomplete, complete, and missed. Heavy bleeding, instability, severe pain, or fever (septic abortion) is ED or obstetric care. Rh-negative patients still need RhoGAM after miscarriage or ectopic pregnancy. Do not send a hemorrhaging patient home with “misoprostol advice from a blog.”

FNP traps: dating a pregnancy only by a late second-trimester fundal height when a first-trimester ultrasound exists; skipping the antibody screen; giving MMR at 12 weeks because rubella IgG was negative; forgetting Tdap until the postpartum visit; treating asymptomatic bacteriuria as optional; missing RhoGAM at 28 weeks; calling unilateral pain and spotting “implantation bleeding”; and discharging preeclampsia without a blood-pressure plan.