The complete pregnancy guide

Your dates: due date, conception, IVF

Knowing your due date is the foundation of every other decision in pregnancy. Standard math uses last menstrual period (LMP) plus 280 days, but real cycles vary, IVF transfers reset the clock, and conception dating is more precise than LMP for most people.

Most US OBs date by LMP at the first appointment, then "recalibrate" at the early ultrasound based on fetal measurements. The recalibrated date is usually the keeper. For IVF, the transfer date is gold standard — your RE clinic's number won't shift.

Trimester essentials

Each trimester has its own questions. First trimester is mostly "what's normal vs concerning?" Second is the calmer middle stretch with the anatomy scan. Third is preparation, growth scans, and the third-trimester planning sprint.

First trimester (weeks 1–12)

Symptoms peak around week 8 for most pregnancies. Nausea, fatigue, breast tenderness — all normal in some combination. Symptoms that aren't normal: severe abdominal pain, heavy bleeding, fever above 100.4°F. Call your OB.

Second trimester (weeks 13–27)

Energy returns. Bump becomes visible. Anatomy scan typically scheduled around 18–22 weeks — this is where structural anomalies are detected and biological sex is confirmed. Glucose tolerance test screening starts at 24–28 weeks for gestational diabetes.

Third trimester (weeks 28–40)

Visits increase from monthly to weekly by week 36. Growth scans for some patients. Group B Strep test around week 36. Hospital tour, birth plan finalization, hospital bag packing. Term begins at 37 weeks.

Maternity leave finance

The US has no federal paid maternity leave. Your paid time off depends on three things: your state, your employer's STD insurance, and your employer's paid parental leave policy. Most parents who plan early get 8–18 paid weeks. Most parents who don't plan get 6–8.

The four sources to know: state Paid Family Leave (15 states + DC have it), employer Short-Term Disability insurance, federal FMLA (12 weeks unpaid, job protection), and employer Paid Parental Leave (varies wildly).

Preparing for arrival

The third trimester is where the practical prep happens. Registry, nursery, hospital bag, name decisions, daycare wait lists, postpartum support setup. Front-load what you can — your last 4 weeks will involve more naps and fewer errands than you think.

Don't over-buy. The biggest registry regret is the 47 outfits in 0–3 month size that were outgrown in three weeks. Conservative quantities of clothing, generous quantities of swaddles and burp cloths.

IVF and fertility journeys

IVF dating is more precise than standard LMP — fertilization timing is documented, embryo development tracked. Most US clinics use day-5 blastocyst transfers; some still do day-3. FET cycles use the embryo's age at freezing, not at thawing. Egg donor cycles use the same math.

The IVF pregnancy experience is different in early weeks (more frequent ultrasounds with the RE), but transitions to standard OB care around 9–10 weeks for most patients.

What's next: after baby arrives

The first weeks are recovery for you and figuring out feeding for both of you. Sleep gets harder before it gets easier. The fourth trimester (the first 12 weeks postpartum) is its own thing — be gentle with expectations.

When you're ready, the rest of our content stack is built around the early baby and toddler years.