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16 weeks pregnant is how many months?
Month 4 (Trimester 2)
Baby development at 16 weeks
How big is my baby? And what does my baby look like?
Your baby is now the size of an avocado, and around 11.6cm in length. He or she will weigh around 100g1. The circulatory system is now starting to run, and can pump over 28 litres of blood a day.
Around now, your baby may start flexing their arms and fingers. Their hands may even be able to meet, form a fist, and hold each other2. As your baby’s nervous system continues to develop, their range of movements will also progress2.
Your baby may also be able to recognise your voice. Studies have shown that babies who hear a song while in the womb react to the same song when it’s sung after they’re born. Choose your lullabies wisely3.
While they’re beginning to make facial expressions, they can’t control them yet2. More importantly, your baby is gearing up for a tremendous growth spurt, more than doubling in weight over the next few weeks4.
Your baby, this week
Discover the science behind your baby's developments, week-by-week
You may not be able to hide your pregnancy any more. That said, baby bumps at 16 weeks are different. Some women may not be showing much at all, while others have visible bumps. Everyone’s different, so don’t worry or waste time comparing your belly to anyone else’s.
The extra hormones in your body are also increasing blood flow to your mucus membranes, so you may feel more congested. Don’t be surprised if you experience the occasional nosebleed due to this, too. Saline sprays and nasal strips are safe to help you ease congestion3.
Hormones can also cause your veins to stretch. Together with increased blood flow, varicose veins may appear. Don’t worry too much - they shrink after you give birth5.
Even if your back is aching from carrying a growing baby, after week 16 only lie or exercise on your back for short periods of time as it can cause low blood pressure and dizziness6.
Pregnancy symptoms at 16 weeks
By now most mums-to-be are free of the unpleasant pregnancy symptoms of their first trimester. However, there are still uncomfortable symptoms that you can experience at 16 weeks, including:
- Continued breast growth and sensitivity
- Constipation Increased vaginal discharge
- Bleeding gums
- Varicose veins
- Back ache
Pregnant women have an increased risk of vitamin D deficiency and need to pay special attention to getting adequate levels7. Taking a daily supplement protects your own health, as well as your baby’s.
If you have dark skin, your increased pigment affects your skin’s ability to generate vitamin D, making a daily supplement even more important. Women of South Asian, African, Caribbean and Middle Eastern descent who live in the UK are particularly at risk7.
Sunlight creates vitamin D naturally, although take great care not to over-expose yourself to the sun. Between October and April, the body uses reserves left over from summer8.
A few foods provide vitamin D, but these are limited. Oily fish, egg yolks and fortified foods are among the few dietary sources. In the UK many people find it difficult to get significant amounts from food alone8.
Because of this, it’s recommended that all pregnant and breastfeeding women take a vitamin D supplement of 10mcg per day. This amount will provide enough for your own needs and help to build the stores your baby needs for the first 6 months of life8.
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Your baby is hungry for vitamin D as it’s essential to help bone development by regulating calcium and phosphate in the body7. A lack of vitamin D can lead to conditions like rickets in children, and osteomalacia (bone pain) in adults7. The good news is that, from early spring to the end of September, you should be able to get plenty of vitamin D from sunlight.
Foods to avoid while pregnant
There's nothing specific to avoid during individual weeks, but throughout your pregnancy, it's wise to give the following a miss:
Raw and undercooked meat
Unpasteurised milk and dairy products
Liver, and excessive consumption of foods high in vitamin A
How much weight should I gain during pregnancy?
Weight gain during pregnancy depends on your pre-pregnancy weight, and varies a great deal from mother to mother. Most women gain between 10kg and 12.5kg (22–28lb) while pregnant, some of which is the weight of the growing baby9.
- NHS Start 4 Life. 2nd trimester, week 16. [Online]. Available at: https://www.nhs.uk/start4life/pregnancy/week-by-week/2nd-trimester/week-16/#anchor-tabs [Accessed October 2019].
- NHS. You and your baby at 13-16 weeks pregnant [Online]. Available at: www.nhs.uk/conditions/pregnancy-and-baby/pages/pregnancy-weeks-13-14-15-16.aspx Page last reviewed: 17 July 2018. Next review due: 17 July 2021.
- What to expect. 16 Weeks Pregnant [Online]. Available at: https://www.whattoexpect.com/pregnancy/week-by-week/week-16.aspx Reviewed October 2019.
- Baby Centre. 16 weeks pregnant: fetal development. Available at: https://www.babycentre.co.uk/16-weeks-pregnant Last reviewed: November 2016.
- What to expect. Varicose Veins During Pregnancy [Online] Available at: https://www.whattoexpect.com/pregnancy/symptoms-and-solutions/varicose-veins.aspx Reviewed January 2018.
- Tommy’s. 16 weeks pregnant - all you need to know [Online]. Available at: https://www.tommys.org/pregnancy-week-by-week/16-weeks-pregnant-whats-happening Last reviewed: June 25th, 2018. Next review: June 25th, 2021.
- NHS. Vitamin D [Online]. Available at: https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/ Reviewed March 2017. Page last reviewed: 3 March 2017. Next review due: 3 March 2020.
- NHS. How to get vitamin D from sunlight [Online]. Available at: www.nhs.uk/Livewell/Summerhealth/Pages/vitamin-D-sunlight.aspx Page last reviewed: 31 August 2018. Next review due: 31 August 2021.
- NHS choices. How much weight will I put on during my pregnancy? [Online]. Available at: https://www.nhs.uk/chq/Pages/2311.aspx?CategoryID=54 Page last reviewed: 18 October 2018. Next review due: 18 October 2021.
Questions about feeding and nutrition?
Our midwives, nutritionists and feeding advisors are always on hand to talk about feeding your baby. So if you have a question, just get in touch.