Morning sickness
Why nausea and vomiting happen in pregnancy, when they ease, what helps and when to call a doctor.
3 min read
First trimester
Week 12 of pregnancy
Your baby is the size of a plum. It opens and closes its fingers, the kidneys start to make urine and the bones harden.
Your baby is the size of a plum
- Length, head to bottom
- ≈ 5.4 cm
- Weight
- ≈ 14 g
Your baby this week
- The baby has reflexes: it opens and closes its fingers and may pull its hand away when it touches something.
- The kidneys start to make urine, which passes into the amniotic fluid.
- The bones, which were soft cartilage, begin to harden.
- The intestines, which grew partly inside the umbilical cord, move back into the tummy.
Your body this week
- Your womb has risen above the pelvic bone, and a doctor may be able to feel it low in your tummy.
- Many women feel more energetic as nausea eases.
- The risk of miscarriage falls markedly after this point.
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General information written by the mam.al editors. Every pregnancy is different and sizes are averages; it does not replace advice from your doctor or midwife. Sources include the NHS week-by-week guide to pregnancy. NHS. Contains public sector information licensed under the Open Government Licence v3.0.