Your baby this week

About as heavy as a large phool gobi (cauliflower, 6–7 in head, with leaves).

Your baby's pupils can usually react to light now.

Their immune system keeps growing. Antibodies from you help.

You this week

Weight gain and trouble sleeping are common now.

Some get a burst of energy to get things ready — often called nesting.

Week 33 of pregnancy

Your baby this week

About 2103 g (estimated weight; Source: WHO fetal growth charts (Kiserud et al., PLoS Med 2017)) — about as heavy as a large phool gobi (cauliflower, 6–7 in head, with leaves) (Source: USDA SR Legacy (FoodData Central) FDC 169986 'Cauliflower, raw': portion '1 head large (6-7" dia.)' = 840 g edible portion; SR28 FOOD_DES refuse 61% (Leaf stalks, cores and trimmings). As-purchased weight = 840 / (1 - 0.61) = 2153.8 g.). Every baby grows a little differently.

How your baby is developing

  • Pupils can typically react to light.UNSW Embryology (CC-BY)
  • The immune system continues developing, aided by antibodies passed from the mother.ACOG

How you may feel

  • Continued weight gain, shortness of breath, and trouble sleeping are common.NHS
  • Some notice a burst of energy and the urge to prepare ('nesting'), though this varies widely.ACOG

Nutrition this week

  • Iron — build fetal stores for the first 6 months of life (Red meat)
  • DHA (omega-3) — peak fetal brain + eye growth
  • Calcium — final bone mineralisation (Dairy)

When to reach out

  • Heavy vaginal bleeding or passing clots.ACOG
  • Severe or persistent abdominal or pelvic pain.ACOG
  • Severe, persistent nausea or vomiting that prevents keeping any fluids down (possible hyperemesis gravidarum).NHS
  • Fever of 38°C (100.4°F) or higher, or chills.WHO
  • Severe dizziness, fainting, or a racing/irregular heartbeat.NHS
  • Pain or burning when urinating (possible urinary tract infection).NHS
  • A severe or persistent headache that doesn't improve.ACOG
  • Sudden swelling of the face, hands, or feet.ACOG
  • Visual disturbances — blurring, flashing lights, or spots.ACOG
  • Regular contractions, pelvic pressure, or low back pain before 37 weeks (possible signs of preterm labor).ACOG
  • Fluid leaking or gushing from the vagina (possible ruptured membranes).NHS
  • Persistent pain in the upper abdomen, especially under the ribs on the right side.ACOG
  • A noticeable reduction in the baby's usual movements, or no movement felt — contact your midwife or doctor promptly rather than waiting; do not wait until the next appointment.ACOG
  • Regular, painful contractions before 37 weeks, or any contraction pattern that concerns you near term.ACOG
  • Waters breaking, or blood-stained ('bloody show') discharge — a normal sign labor may be starting at term, but call your midwife or doctor to be checked.NHS

These apply to this week specifically. See the full list of urgent warning signs the CDC publishes for pregnancy and the year after birth.

Part of the Third trimester (weeks 28–42).

Educational reference only — not medical advice. Typical/average figures; every pregnancy differs. Always consult your doctor or midwife. Seek urgent care for any warning sign.

Tips for this stage

  • Continue dates and gheeSource: Al-Kuran et al. 2011, Journal of Obstetrics and Gynaecology 31(1)
  • Warm soups for dinnerSource: NHS — Indigestion and heartburn in pregnancy

Checklist

  • Pediatrician selectedSource: HealthyChildren.org (AAP) — Finding a Pediatrician
  • Car seat installedSource: CDC — Child Passenger Safety resources