# Day 131: One leg, not two

> Two puffy ankles at the end of the day is common. One swollen, painful calf is a phone call today. Learn the difference once and keep it.

- Series: Your fifth month of pregnancy, day by day (https://chorevia.com/learn/pregnancy-month-5), day 131 of 280, 18 weeks + 5 days
- Your baby this week: about the size of a bell pepper; around 14.2 cm from head to bottom
- Canonical URL: https://chorevia.com/learn/pregnancy-month-5/day-131
- Last reviewed: 2026-10-22
- Publisher: Chorevia (https://chorevia.com)
- Cite as: Chorevia. "Day 131: One leg, not two." Last reviewed October 22, 2026. https://chorevia.com/learn/pregnancy-month-5/day-131

This guide is general education that summarizes published research and guidance from groups like the American Academy of Pediatrics, the CDC, and the WHO. It isn’t medical advice, and every child develops on their own timeline. Your pediatrician knows your child; if something feels wrong, call them. In an emergency, call 911.

Eighteen weeks and five days. Today's note is short and specific, because the thing it teaches is easy to confuse with something ordinary.

## Your baby

The sucking reflex is developing this week ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-18/)), the one that will find a breast or a bottle within an hour of birth. Your baby is around 14.2cm from head to bottom, about the size of a bell pepper ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-18/)).

## Your body

Two things from the NHS's week 18 page. Your breasts may have grown a cup size by now, especially in a first pregnancy ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-18/)). And your blood pressure is probably lower than it was, so standing up quickly can make you dizzy ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-18/)).

Now the thing to learn. MedlinePlus: "Pain and swelling in one leg but not the other can signal a blood clot," and you should let your provider know right away ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)). The CDC puts "Severe swelling, redness, or pain of your leg or arm" on its list of urgent maternal warning signs, at any time in pregnancy and up to 6 weeks after birth ([CDC](https://www.cdc.gov/hearher/maternal-warning-signs/index.html)).

## Try today

### The one-leg rule

- **Time:** 3 minutes

1. Say it out loud once: one leg, not two. One calf that is swollen, red, warm, or painful, when the other isn't, is a call today ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)).
2. Write it on the call-line card on the fridge, under whatever's already there: "One leg swollen or painful: call right away" ([CDC](https://www.cdc.gov/hearher/maternal-warning-signs/index.html)).
3. Tell your partner the rule, so that if you say "my calf's sore" one evening, they say "one or both?"
4. Tonight, when you take your shoes off, look at both ankles. That's your baseline for what "both" looks like.

**Make it work:** This is a rule, not a worry. You learn it once, the way you learned where the fire exit is, and then you stop thinking about it.

## Watch for

- **Normal:** both ankles puffy at the end of a long day; swelling is on the NHS's list of ordinary symptoms around now ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-19/)). **Call your provider right away** for pain and swelling in one leg but not the other ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)).
- **Normal:** feeling your heart thump after the stairs. **Call 911** for chest pain or a fast-beating heart, or trouble breathing; all three are urgent warning signs ([CDC](https://www.cdc.gov/hearher/maternal-warning-signs/index.html)), and MedlinePlus says severe chest pain or shortness of breath that does not go away means 911 or the emergency room ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000583.htm)).
- **Normal:** more vaginal discharge than before pregnancy. **Call your provider** if it has a foul odor, a greenish colour, itching, or pain; infections matter because they may cause preterm labor ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000583.htm)).

## For you

Two swollen ankles at the end of the day are a different, common thing. The NHS's later pages describe swelling in the ankles, feet and face, especially in hot weather, as probably water retention, though it should be checked for pre-eclampsia ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/3rd-trimester/week-28/)). For the ordinary kind, the OWH suggests eight to 10 glasses of fluids a day, less caffeine and salt, resting with your feet raised, and asking about support hose ([OWH](https://womenshealth.gov/pregnancy/youre-pregnant-now-what/body-changes-and-discomforts)).

If you're the partner: you are the "one or both?" person now. It's a two-word job, and it matters.

## Sources

- NHS. "Week 18." Week-by-week guide to pregnancy, Best Start in Life. https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-18/
- MedlinePlus. "Aches and pains during pregnancy." National Library of Medicine. https://medlineplus.gov/ency/patientinstructions/000580.htm
- Centers for Disease Control and Prevention. "Urgent Maternal Warning Signs and Symptoms." HEAR HER campaign, 2024. https://www.cdc.gov/hearher/maternal-warning-signs/index.html
- NHS. "Week 19." Week-by-week guide to pregnancy, Best Start in Life. https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-19/
- MedlinePlus. "Common symptoms during pregnancy." National Library of Medicine. https://medlineplus.gov/ency/patientinstructions/000583.htm
- NHS. "Week 28." Week-by-week guide to pregnancy, Best Start in Life. https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/3rd-trimester/week-28/
- Office on Women's Health. "Body changes and discomforts." U.S. Department of Health and Human Services. https://womenshealth.gov/pregnancy/youre-pregnant-now-what/body-changes-and-discomforts