# Day 107: The jab in the side

> Fifteen weeks and two days. A sharp jab at the side of the bump is usually round ligament pain and eases with rest. Today you learn the four-step rule for it.

- Series: Your fourth month of pregnancy, day by day (https://chorevia.com/learn/pregnancy-month-4), day 107 of 280, 15 weeks + 2 days
- Your baby this week: about the size of an apple; around 10.1 cm from head to bottom
- Canonical URL: https://chorevia.com/learn/pregnancy-month-4/day-107
- Last reviewed: 2026-10-22
- Publisher: Chorevia (https://chorevia.com)
- Cite as: Chorevia. "Day 107: The jab in the side." Last reviewed October 22, 2026. https://chorevia.com/learn/pregnancy-month-4/day-107

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.

Fifteen weeks and two days. The pain this note is about is sharp, brief and alarming the first time. Today you get its name, its usual timing, and a rule so you're not deciding what to do while it's happening.

## Your baby

Around 10.1cm long from head to bottom, about the size of an apple ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)). The baby's eyes are sensitive to light ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)), and the baby grows quickly in there, protected by the amniotic sac and fluid and fed by the placenta ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)). A jab in your side is a stretch in you, not a knock to the baby.

## Your body

The NHS describes an occasional jabbing pain on the sides of the bump, round ligament pain, which may ease with rest ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)). It most often occurs between 18 and 24 weeks; moving slowly or changing positions may help, and a maternity girdle may be useful ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)). So if you haven't felt it, it may still be coming, and if you have, you're a little early to the usual window.

What it is not: constant. MedlinePlus says to see your provider right away for constant, severe abdominal pain, possible contractions, or pain with bleeding or fever ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)). The rule below is built on that line.

## Try today

### The side-jab rule

- **Time:** 10 minutes, when it happens

1. Stop what you're doing.
2. Change position: sit if you're standing, roll onto your side if you're lying down. Moving slowly or changing positions may help ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)).
3. Rest. The NHS says it may ease with rest ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)).
4. Recheck in ten minutes. A jab that has gone, or is fading, is the ordinary kind.
5. Pain that stays, that's severe, or that comes with bleeding or fever: see your provider right away ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)).

**Make it work:** Say the four words to your partner tonight: stop, change, rest, recheck. Then they can say them back to you when it jabs.

## Watch for

- **Normal:** an occasional jab at the side of the bump that eases with rest ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)). **Call your provider right away** for constant, severe abdominal pain, possible contractions, or pain with bleeding or fever ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)).
- **Normal:** a backache that eases when you lie down, rest, or apply heat ([OWH](https://womenshealth.gov/pregnancy/youre-pregnant-now-what/body-changes-and-discomforts)). **Call your provider** if the pain does not get better ([OWH](https://womenshealth.gov/pregnancy/youre-pregnant-now-what/body-changes-and-discomforts)).
- **Normal:** hands that feel numb on waking; MedlinePlus says a wrist brace at night can help ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)). **Call your provider** to check any persistent numbness, tingling or weakness in an arm or leg ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)).
- **Normal:** ten days of notes and a longer list of warning signs than you've ever had. **Call your provider** if you feel like something just isn't right, even if it isn't on the list; the CDC says to contact them if something seems wrong ([CDC](https://www.cdc.gov/hearher/maternal-warning-signs/index.html)).

## For you

The whole of today in one line: a jab stops; pain that stays gets a call. The NHS's word for the ordinary kind is "occasional" ([NHS](https://www.nhs.uk/best-start-in-life/pregnancy/week-by-week-guide-to-pregnancy/2nd-trimester/week-15/)), and MedlinePlus's word for the kind to see someone about is "constant" ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)). You don't have to be a diagnostician. You have to notice which word fits.

One more habit from the same page, for the back rather than the side: bend your knees, not your waist, when you pick something up ([MedlinePlus](https://medlineplus.gov/ency/patientinstructions/000580.htm)). It will matter more every week from here.

If you're the partner: when she stops on the path with a hand at her side, don't ask twenty questions. Say the four words, find a bench, and watch the clock with her.

## Sources

- NHS. "Week 15." 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-15/
- MedlinePlus. "Aches and pains during pregnancy." National Library of Medicine. https://medlineplus.gov/ency/patientinstructions/000580.htm
- 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
- 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