The Best Maternity Underwear For Each Trimester

When it comes to having babies, there are much more important things to consider than the kind of briefs you’ve got on. However, the underwear you wear during and after your pregnancy can heavily affect your comfort. Sometimes, it can even affect your health. To ensure you and your baby remain happy throughout the 9 months, we’ve recommended the best maternity underwear to sport throughout your pregnancy. 

Related: The Best Post-Pregnancy Bras to Fix Your Dilemmas

The best underwear for your first trimester (1-12 weeks)

During your first trimester, your body undergoes many changes as your baby grows from the size of a poppy seed to the size of a clementine. Most notably during your first trimester, your breasts will feel bigger and more tender, especially after the 4-5 week mark. Your womb will also start to expand, meaning your midriff will gradually get larger.

The best underwear for this period doesn’t have to strictly be maternity underwear, as your bump and your breasts are still at the smallest they will be throughout your pregnancy. The main priority here is a comfortable fit.


  • Sexy pregnancy underwear is not out of the question. So to feel as confident as possible, try a comfortable full cup bra with lace trims.
  • Opt for bras around 2 cup sizes and 2 back sizes bigger than you were pre-pregnancy, this should last you throughout the first trimester at least.
  • Soft cup maternity bras have no underwiring so nothing will dig into your ribs. You’ll find these especially useful after the first 4 weeks.


  • As secretions increase during this stage, you’re at a higher chance of developing an infection down there. So, try to avoid this by wearing breathable cotton knickers.
  • As your bump isn’t too big yet, you can get away with most types of knickers, just avoid tight or restrictive pants such as Spanx.
  • Sexy maternity lingerie, such as maternity thongs or knickers with lace details, are still suitable options. Just ensure they sit underneath or over your bump without being too tight.

The best underwear for your second trimester (13-27 weeks)

Your second trimester is where your pregnancy is more notably visible.  According to Bupa, the 20th week is when most women ‘look pregnant’. During this time, you can also expect a weight gain of around 20-25 pounds, as well as a larger abdomen and breasts.

Your hormones will cause your ligaments to relax, meaning looser joints. This combined with the weight you’re carrying could cause some aches and pains, especially for your back. This is why your main priority with maternity underwear in your second trimester should be support. 


  • Due to the added weight, the bras from the first trimester may not be cutting it anymore. Remeasure yourself if need be to find a more comfortable maternity bra.
  • A full cup bra offers more support for breasts on the larger side. If you find these aren’t comfortable enough don’t be afraid to try a sports bra for everyday wear.
  • Bras with wider straps will offer you more support than skimpier numbers.


  • For added support, over the bump maternity knickers are high waist knickers that cover your belly and cradle your bump. While these may feel a bit snug, they help distribute your weight evenly. Most of these knickers are also seamless so you won’t see any panty lines.
  • Low rise maternity underwear is ideal for those who don’t want their bump covered but who still want to feel comfortable. These knickers often come in a V-shape to avoid touching your belly.
  • Fold over underwear is the best option if you can’t decide between the two, as you can unfold these knickers to support your bump, or fold them over on days where you’d like your belly to be unrestricted. 

The best underwear for your third trimester (28-40 weeks)

In your final trimester, your baby is nearly fully developed, however, that means more bodily changes for you.  Swelling around the ankles and hands are occasionally reported by pregnant women, as well as Braxton-Hicks contractions and heartburn. Your breasts may also start to leak a milky fluid and sometimes your bladder control may weaken. However, on the positive side, your baby should be in proportion and ready to meet you soon!


  • Because of your leaky breasts, extra padding may be the best option. Opt for a maternity bra with padded cups, for extra breathability ensure it’s cotton.
  • Because of the weight gain and swelling, it’s again advised to consider a soft cup bra without underwiring to ensure maximum comfort.


  • Whether you opt for low-rise, fold-over or over the bump knickers is completely up to personal preference and all will provide comfort during this trimester.
  • For your knickers, opt for cotton maternity lingerie for breathability and also absorbance.
  • If you’re heading to the hospital, disposable maternity underwear is ideal to take with you as they’re thin and lightweight and means you won’t have to throw away your favourite knickers post-delivery. 

The best underwear for post-pregnancy

Post-baby your body is likely to be sore and is slowly adjusting back to how you looked pre-pregnancy. Therefore, your belly may feel saggy or squishy, which is understandable considering how much it has stretched. As well as this your breasts are still going to be producing milk, which may mean they feel sensitive and tender. You’re also likely to have some discharge that will feel like a heavy period. 


  • If you decide to breastfeed your baby, a nursing bra is specially designed so you can unhook the cups and provide easy access for your baby to feed.
  • Padded, cotton full cup maternity bras are again the best way to go for padded comfort and support post-pregnancy.


  • It’s understandable to want more support for your stomach. There's plenty of specially designed support underwear after pregnancy, including high waisted briefs to help tighten and control your mid-section.
  • Because of the bleeding, disposable maternity briefs might still be your friend for a week after giving birth. After this, you may wish to switch to comfortable cotton underwear accompanied with sanitary towels.

Browse our maternity section to find the best pregnancy underwear for your needs.

Written by Lauren

Lauren is a Fashion graduate from Plymouth College of Art. She is a Creative Content & Social Media Executive for Lingerie Outlet Store by day and a lingerie designer by night. With her expertise in design and bra fitting, Lauren delivers her knowledge and her passion through her writing.

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